Whistle's Netgraph link-layer (sometimes more) networking infrastructure.

Been in production for 3 years now. Gives Instant Frame relay to if_sr
and if_ar drivers, and PPPOE support soon. See:
ftp://ftp.whistle.com/pub/archie/netgraph/index.html
for on-line manual pages.

Reviewed by: Doug Rabson (dfr@freebsd.org)
Obtained from:  Whistle CVS tree

16 files changed, 2733 insertions, 0 deletions

diff --git a/share/man/man4/netgraph.4 b/share/man/man4/netgraph.4
new file mode 100644
index 0000000..c90650e0
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@@ -0,0 +1,876 @@
+.\" Copyright (c) 1996-1999 Whistle Communications, Inc.
+.\" All rights reserved.
+.\" 
+.\" Subject to the following obligations and disclaimer of warranty, use and
+.\" redistribution of this software, in source or object code forms, with or
+.\" without modifications are expressly permitted by Whistle Communications;
+.\" provided, however, that:
+.\" 1. Any and all reproductions of the source or object code must include the
+.\"    copyright notice above and the following disclaimer of warranties; and
+.\" 2. No rights are granted, in any manner or form, to use Whistle
+.\"    Communications, Inc. trademarks, including the mark "WHISTLE
+.\"    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
+.\"    such appears in the above copyright notice or in the software.
+.\" 
+.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
+.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
+.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
+.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
+.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
+.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
+.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
+.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
+.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
+.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
+.\" OF SUCH DAMAGE.
+.\" 
+.\" Authors: Julian Elischer <julian@whistle.com>
+.\"          Archie Cobbs <archie@whistle.com>
+.\"
+.\" $FreeBSD$
+.\" $Whistle: netgraph.4,v 1.7 1999/01/28 23:54:52 julian Exp $
+.\"
+.Dd January 19, 1999
+.Dt NETGRAPH 4
+.Os FreeBSD
+.Sh NAME
+.Nm netgraph
+.Nd graph based kernel networking subsystem
+.Sh DESCRIPTION
+The
+.Nm 
+system provides a uniform and modular system for the implementation
+of kernel objects which perform various networking functions. The objects,
+known as 
+.Em nodes ,
+can be arranged into arbitrarily complicated graphs. Nodes have
+.Em hooks
+which are used to connect two nodes together, forming the edges in the graph.
+Nodes communicate along the edges to process data, implement protocols, etc.
+.Pp
+The aim of
+.Nm 
+is to supplement rather than replace the existing kernel networking
+infrastructure. It provides:
+.Pp
+.Bl -bullet -compact -offset 2n
+.It
+A flexible way of combining protocol and link level drivers
+.It
+A modular way to implement new protocols
+.It
+A common framework for kernel entities to inter-communicate
+.It
+A reasonably fast, kernel-based implementation
+.El
+.Sh Nodes and Types
+The most fundamental concept in
+.Nm
+is that of a
+.Em node .
+All nodes implement a number of predefined methods which allow them
+to interact with other nodes in a well defined manner.
+.Pp
+Each node has a
+.Em type ,
+which is a static property of the node determined at node creation time.
+A node's type is described by a unique ASCII type name.
+The type implies what the node does and how it may be connected
+to other nodes.
+.Pp
+In object-oriented language, types are classes and nodes are instances
+of their respective class. All node types are subclasses of the generic node
+type, and hence inherit certain common functionality and capabilities
+(e.g., the ability to have an ASCII name).
+.Pp
+Nodes may be assigned a globally unique ASCII name which can be
+used to refer to the node.
+The name must not contain the characters ``.'' or  ``:'' and is limited to
+.Dv "NG_NODELEN + 1"
+characters (including NUL byte).
+.Pp
+Each node instance has a unique
+.Em ID number
+which is expressed as a 32-bit hex value. This value may be used to
+refer to a node when there is no ASCII name assigned to it.
+.Sh Hooks
+Nodes are connected to other nodes by connecting a pair of
+.Em hooks ,
+one from each node. Data flows bidirectionally between nodes along
+connected pairs of hooks.  A node may have as many hooks as it
+needs, and may assign whatever meaning it wants to a hook.
+.Pp
+Hooks have these properties:
+.Pp
+.Bl -bullet -compact -offset 2n
+.It
+A hook has an ASCII name which is unique among all hooks
+on that node (other hooks on other nodes may have the same name).
+The name must not contain a ``.'' or a ``:''  and is
+limited to
+.Dv "NG_HOOKLEN + 1"
+characters (including NUL byte).
+.It
+A hook is always connected to another hook. That is, hooks are
+created at the time they are connected, and breaking an edge by
+removing either hook destroys both hooks.
+.El
+.Pp
+A node may decide to assign special meaning to some hooks. 
+For example, connecting to the hook named ``debug'' might trigger
+the node to start sending debugging information to that hook.
+.Sh Data Flow
+Two types of information flow between nodes: data messages and
+control messages. Data messages are passed in mbuf chains along the edges
+in the graph, one edge at a time. The first mbuf in a chain must have the
+.Dv M_PKTHDR
+flag set. Each node decides how to handle data coming in on its hooks.
+.Pp
+Control messages are type-specific structures sent from one node directly
+to an arbitrary other node. There are two ways to address such a message. If
+there is a sequence of edges connecting the two nodes, the message
+may be ``source routed'' by specifying the corresponding sequence
+of hooks as the destination address for the message (relative
+addressing).  Otherwise, the recipient node global ASCII name
+(or equivalent ID based name) is used as the destination address
+for the message (absolute addressing).  The two types of addressing
+may be combined, by specifying an absolute start node and a sequence
+of hooks.
+.Pp
+Messages often represent commands that are followed by a reply message
+in the reverse direction. To facilitate this, the recipient of a
+control message is supplied with a ``return address'' that is suitable
+for addressing a reply.
+.Pp
+Each control message contains a 32 bit value called a
+.Em typecookie
+indicating the type of the message, i.e., how to interpret it.
+Typically each type defines a unique typecookie for the messages
+that it understands.  However, a node may choose to recognize and
+implement more than one type of message.
+.Sh Netgraph is Functional
+In order to minimize latency, most
+.Nm netgraph
+operations are functional.
+That is, data and control messages are delivered by making function
+calls rather than by using queues and mailboxes.  For example, if node
+A wishes to send a data mbuf to neighboring node B, it calls the
+generic
+.Nm
+data delivery function. This function in turn locates
+node B and calls B's ``receive data'' method. While this mode of operation
+results in good performance, it has a few implications for node
+developers:
+.Pp
+.Bl -bullet -compact -offset 2n
+.It
+Whenever a node delivers a data or control message, the node
+may need to allow for the possibility of receiving a returning message
+before the original delivery function call returns.
+.It
+Netgraph nodes and support routines generally run at
+.Dv "splnet()" .
+However, some nodes may want to send data and control messages
+from a different priority level. Netgraph supplies queueing routines which
+utilize the NETISR system to move message delivery to 
+.Dv "splnet()" .
+Note that messages are always received at
+.Dv "splnet()" .
+.It
+It's possible for an infinite loop to occur if the graph contains cycles.
+.El
+.Pp
+So far, these issues have not proven problematical in practice.
+.Sh Interaction With Other Parts of the Kernel
+A node may have a hidden interaction with other components of the
+kernel outside of the
+.Nm
+subsystem, such as device hardware,
+kernel protocol stacks, etc.  In fact, one of the benefits of
+.Nm
+is the ability to join disparate kernel networking entities together in a
+consistent communication framework.
+.Pp
+An example is the node type
+.Em socket 
+which is both a netgraph node and a
+.Xr socket 2
+BSD socket in the protocol family
+.Dv PF_NETGRAPH .
+Socket nodes allow user processes to participate in
+.Nm netgraph .
+Other nodes communicate with socket nodes using the usual methods, and the
+node hides the fact that it is also passing information to and from a
+cooperating user process.
+.Pp
+Another example is a device driver that presents
+a node interface to the hardware.
+.Sh Node Methods
+Nodes are notified of the following actions via function calls
+to the following node methods (all at
+.Dv "splnet()" )
+and may accept or reject that action (by returning the appropriate
+error code):
+.Bl -tag -width xxx
+.It Creation of a new node
+The constructor for the type is called. If creation of a new node is 
+allowed, the constructor must call the generic node creation
+function (in object-oriented terms, the superclass constructor)
+and then allocate any special resources it needs. For nodes that
+correspond to hardware, this is typically done during the device
+attach routine. Often a global ASCII name corresponding to the
+device name is assigned here as well.
+.It Creation of a new hook
+The hook is created and tentatively
+linked to the node, and the node is told about the name that will be 
+used to describe this hook. The node sets up any special data structures
+it needs, or may reject the connection, based on the name of the hook.
+.It Successful connection of two hooks
+After both ends have accepted their
+hooks, and the links have been made, the nodes get a chance to
+find out who their peer is across the link and can then decide to reject
+the connection. Tear-down is automatic.
+.It Destruction of a hook
+The node is notified of a broken connection. The node may consider some hooks
+to be critical to operation and others to be expendable: the disconnection
+of one hook may be an acceptable event while for another it
+may effect a total shutdown for the node.
+.It Shutdown of a node
+This method allows a node to clean up
+and to ensure that any actions that need to be performed
+at this time are taken. The method must call the generic (i.e., superclass)
+node destructor to get rid of the generic components of the node.
+Some nodes (usually associated with a piece of hardware) may be
+.Em persistent
+in that a shutdown breaks all edges and resets the node,
+but doesn't remove it, in which case the generic destructor is not called.
+.El
+.Sh Sending and Receiving Data
+Three other methods are also supported by all nodes:
+.Bl -tag -width xxx
+.It Receive data message
+An mbuf chain is passed to the node.
+The node is notified on which hook the data arrived,
+and can use this information in its processing decision.
+The node must must always 
+.Dv m_freem()
+the mbuf chain on completion or error, or pass it on to another node
+(or kernel module) which will then be responsible for freeing it.
+.Pp
+In addition to the mbuf chain itself there is also a pointer to a 
+structure describing meta-data about the message
+(e.g. priority information). This pointer may be
+.Dv NULL
+if there is no additional information. The format for this information is
+described in 
+.Dv netgraph.h .
+The memory for meta-data must allocated via
+.Dv malloc()
+with type
+.Dv M_NETGRAPH .
+As with the data itself, it is the receiver's responsibility to
+.Dv free()
+the meta-data. If the mbuf chain is freed the meta-data must
+be freed at the same time. If the meta-data is freed but the
+real data on is passed on, then a
+.Dv NULL
+pointer must be substituted.
+.Pp
+The receiving node may decide to defer the data by queueing it in the
+.Nm
+NETISR system (see below).
+.Pp
+The structure and use of meta-data is still experimental, but is presently used in
+frame-relay to indicate that management packets should be queued for transmission
+at a higher priority than data packets. This is required for
+conformance with Frame Relay standards.
+.Pp
+.It Receive queued data message
+Usually this will be the same function as 
+.Em Receive data message.
+This is the entry point called when a data message is being handed to 
+the node after having been queued in the NETISR system.
+This allows a node to decide in the 
+.Em Receive data message
+method that a message should be defered and queued,
+and be sure that when it is processed from the queue,
+it will not be queued again.
+.It Receive control message
+This method is called when a control message is addressed to the node.
+A return address is always supplied, giving the address of the node
+that originated the message so a reply message can be sent anytime later.
+.Pp
+It is possible for a synchronous reply to be made, and in fact this
+is more common in practice.
+This is done by setting a pointer (supplied as an extra function parameter)
+to point to the reply.
+Then when the control message delivery function returns,
+the caller can check if this pointer has been made non-NULL,
+and if so then it points to the reply message allocated via
+.Dv malloc()
+and containing the synchronous response. In both directions, 
+(request and response) it is up to the 
+receiver of that message to 
+.Dv free()
+the control message buffer. All control messages and replies are
+allocated with
+.Dv malloc()
+type
+.Dv M_NETGRAPH .
+.El
+.Pp
+Much use has been made of reference counts, so that nodes being
+free'd of all references are automatically freed, and this behaviour
+has been tested and debugged to present a consistent and trustworthy
+framework for the ``type module'' writer to use.
+.Sh Addressing
+The 
+.Nm
+framework provides an unambiguous and simple to use method of specifically
+addressing any single node in the graph. The naming of a node is 
+independent of its type, in that another node, or external component
+need not know anything about the node's type in order to address it so as 
+to send it a generic message type. Node and hook names should be
+chosen so as to make addresses meaningful.
+.Pp
+Addresses are either absolute or relative. An absolute address begins
+with a node name, (or ID), followed by a colon, followed by a sequence of hook
+names separated by periods. This addresses the node reached by starting
+at the named node and following the specified sequence of hooks.
+A relative address includes only the sequence of hook names, implicitly
+starting hook traversal at the local node.
+.Pp
+There are a couple of special possibilities for the node name.
+The name ``.'' (refered to as ``.:'') always refers to the local node.
+Also, nodes that have no global name may be addressed by their ID numbers,
+by enclosing the hex representation of the ID number within square brackets.
+Here are some examples of valid netgraph addresses:
+.Bd -literal -offset 4n -compact
+
+  .:
+  foo:
+  .:hook1
+  foo:hook1.hook2
+  [f057cd80]:hook1
+.Ed
+.Pp
+Consider the following set of nodes might be created for a site with
+a single physical frame relay line having two active logical DLCI channels,
+with RFC-1490 frames on DLCI 16 and PPP frames over DLCI 20:
+.Pp
+.Bd -literal
+[type SYNC ]                  [type FRAME]                 [type RFC1490]
+[ "Frame1" ](uplink)<-->(data)[<un-named>](dlci16)<-->(mux)[<un-named>  ]
+[    A     ]                  [    B     ](dlci20)<---+    [     C      ]
+                                                      |
+                                                      |      [ type PPP ]
+                                                      +>(mux)[<un-named>]
+                                                             [    D     ]
+.Ed
+.Pp
+One could always send a control message to node C from anywhere
+by using the name
+.Em "Frame1:uplink.dlci16" .
+Similarly, 
+.Em "Frame1:uplink.dlci20"
+could reliably be used to reach node D, and node A could refer
+to node B as
+.Em ".:uplink" ,
+or simply
+.Em "uplink" .
+Conversely, B can refer to A as
+.Em "data" .
+The address
+.Em "mux.data"
+could be used by both nodes C and D to address a message to node A.
+.Pp
+Note that this is only for
+.Em control messages .
+Data messages are routed one hop at a time, by specifying the departing
+hook, with each node making the next routing decision. So when B
+receives a frame on hook
+.Em data
+it decodes the frame relay header to determine the DLCI,
+and then forwards the unwrapped frame to either C or D.
+.Pp
+A similar graph might be used to represent multi-link PPP running
+over an ISDN line:
+.Pp
+.Bd -literal
+[ type BRI ](B1)<--->(link1)[ type MPP  ]
+[  "ISDN1" ](B2)<--->(link2)[ (no name) ]
+[          ](D) <-+
+                  |
+ +----------------+
+ |
+ +->(switch)[ type Q.921 ](term1)<---->(datalink)[ type Q.931 ]
+            [ (no name)  ]                       [ (no name)  ]
+.Ed
+.Sh Netgraph Structures
+Interesting members of the node and hook structures are shown below:
+.Bd -literal
+struct  ng_node {
+  char    *name;                /* Optional globally unique name */
+  void    *private;             /* Node implementation private info */
+  struct  ng_type *type;        /* The type of this node */
+  int     refs;                 /* Number of references to this struct */
+  int     numhooks;             /* Number of connected hooks */
+  hook_p  hooks;                /* Linked list of (connected) hooks */
+};
+typedef struct ng_node *node_p;
+
+struct  ng_hook {
+  char           *name;         /* This node's name for this hook */
+  void           *private;      /* Node implementation private info */
+  int            refs;          /* Number of references to this struct */
+  struct ng_node *node;         /* The node this hook is attached to */
+  struct ng_hook *peer;         /* The other hook in this connected pair */
+  struct ng_hook *next;         /* Next in list of hooks for this node */
+};
+typedef struct ng_hook *hook_p;
+.Ed
+.Pp
+The maintenance of the name pointers, reference counts, and linked list
+of hooks for each node is handled automatically by the
+.Nm
+subsystem.
+Typically a node's private info contains a back-pointer to the node or hook
+structure, which counts as a new reference that must be registered by
+incrementing
+.Dv "node->refs" .
+.Pp
+From a hook you can obtain the corresponding node, and from
+a node the list of all active hooks.
+.Pp
+Node types are described by this structure:
+.Bd -literal
+struct ng_type {
+  u_int32_t version;                    /* Must equal NG_VERSION */
+  const  char *name;                    /* Unique type name */
+
+  /* Module event handler */
+  modeventhand_t  mod_event;            /* Handle load/unload (optional) */
+
+  /* Constructor */
+  int    (*constructor)(node_p *node);  /* Create a new node */
+
+  /** Methods using the node **/
+  int    (*rcvmsg)(node_p node,         /* Receive control message */
+            struct ng_mesg *msg,                /* The message */
+            const char *retaddr,                /* Return address */
+            struct ng_mesg **resp);             /* Synchronous response */
+  int    (*shutdown)(node_p node);      /* Shutdown this node */
+  int    (*newhook)(node_p node,        /* create a new hook */
+            hook_p hook,                        /* Pre-allocated struct */
+            const char *name);                  /* Name for new hook */
+
+  /** Methods using the hook **/
+  int    (*connect)(hook_p hook);       /* Confirm new hook attachment */
+  int    (*rcvdata)(hook_p hook,        /* Receive data on a hook */
+            struct mbuf *m,                     /* The data in an mbuf */
+            meta_p meta);                       /* Meta-data, if any */
+  int    (*disconnect)(hook_p hook);    /* Notify disconnection of hook */
+};
+.Ed
+.Pp
+Control messages have the following structure:
+.Bd -literal
+#define NG_CMDSTRLEN    15      /* Max command string (16 with null) */
+
+struct ng_mesg {
+  struct ng_msghdr {
+    u_char      version;        /* Must equal NG_VERSION */
+    u_char      spare;          /* Pad to 2 bytes */
+    u_short     arglen;         /* Length of cmd/resp data */
+    u_long      flags;          /* Message status flags */
+    u_long      token;          /* Reply should have the same token */
+    u_long      typecookie;     /* Node type understanding this message */
+    u_long      cmd;            /* Command identifier */
+    u_char      cmdstr[NG_CMDSTRLEN+1]; /* Cmd string (for debug) */
+  } header;
+  char  data[0];                /* Start of cmd/resp data */
+};
+
+#define NG_VERSION      1               /* Netgraph version */
+#define NGF_ORIG        0x0000          /* Command */
+#define NGF_RESP        0x0001          /* Response */
+.Ed
+.Pp
+Control messages have the fixed header shown above, followed by a 
+variable length data section which depends on the type cookie
+and the command. Each field is explained below:
+.Bl -tag -width xxx
+.It Dv version
+Indicates the version of netgraph itself. The current version is
+.Dv NG_VERSION .
+.It Dv arglen
+This is the length of any extra arguments, which begin at
+.Dv data .
+.It Dv flags
+Indicates whether this is a command or a response control message.
+.It Dv token
+The
+.Dv token
+is a means by which a sender can match a reply message to the
+corresponding command message; the reply always has the same token.
+.Pp
+.It Dv typecookie
+The corresponding node type's unique 32-bit value.
+If a node doesn't recognize the type cookie it must reject the message
+by returning
+.Er EINVAL .
+.Pp
+Each type should have an include file that defines the commands,
+argument format, and cookie for its own messages.
+The typecookie
+insures that the same header file was included by both sender and
+receiver; when an incompatible change in the header file is made,
+the typecookie
+.Em must
+be changed.
+The de facto method for generating unique type cookies is to take the
+seconds from the epoch at the time the header file is written
+(i.e., the output of
+.Dv "date -u +'%s'" ")."
+.Pp
+There is a predefined typecookie
+.Dv NGM_GENERIC_COOKIE
+for the ``generic'' node type, and
+a corresponding set of generic messages which all nodes understand.
+The handling of these messages is automatic.
+.It Dv command
+The identifier for the message command. This is type specific,
+and is defined in the same header file as the typecookie.
+.It Dv cmdstr
+Room for a short human readable version of ``command'' (for debugging
+purposes only).
+.El
+.Pp
+Some modules may choose to implement messages from more than one 
+of the header files and thus recognize more than one type cookie. 
+.Sh Generic Control Messages
+There are a number of standard predefined messages that will work
+for any node, as they are supported directly by the framework itself.
+These are defined in
+.Dv ng_message.h
+along with the basic layout of messages and other similar information.
+.Bl -tag -width xxx
+.It Dv NGM_CONNECT
+Connect to another node, using the supplied hook names on either end.
+.It Dv NGM_MKPEER
+Construct a node of the given type and then connect to it using the
+supplied hook names.
+.It Dv NGM_SHUTDOWN
+The target node should disconnect from all its neighbours and shut down.
+Persistent nodes such as those representing physical hardware
+might not dissappear from the node namespace, but only reset themselves.
+The node must disconnect all of its hooks.
+This may result in neighbors shutting themselves down, and possibly a
+cascading shutdown of the entire connected graph.
+.It Dv NGM_NAME
+Assign a name to a node. Nodes can exist without having a name, and this
+is the default for nodes created using the
+.Dv NGM_MKPEER
+method. Such nodes can only be addressed relatively or by their ID number.
+.It Dv NGM_RMHOOK
+Ask the node to break a hook connection to one of its neighbours.
+Both nodes will have their ``disconnect'' method invoked.
+Either node may elect to totally shut down as a result.
+.It Dv NGM_NODEINFO
+Asks the target node to describe itself. The four returned fields
+are the node name (if named), the node type, the node ID and the
+number of hooks attached. The ID is an internal number unique to that node.
+.It Dv NGM_LISTHOOKS
+This returns the information given by
+.Dv NGM_NODEINFO ,
+but in addition 
+includes an array of fields describing each link, and the desription for
+the node at the far end of that link.
+.It Dv NGM_LISTNAMES
+This returns an array of node descriptions (as for
+.Dv NGM_NODEINFO ")"
+where each entry of the array describes a named node.
+All named nodes will be described.
+.It Dv NGM_LISTNODES
+This is the same as
+.Dv NGM_LISTNAMES
+except that all nodes are listed regardless of whether they have a name or not.
+.It Dv NGM_LISTTYPES
+This returns a list of all currently installed netgraph types.
+.It Dv NGM_TEXT_STATUS
+The node may return a text formatted status message.
+The status information is determined entirely by the node type.
+It is the only "generic" message
+that requires any support within the node itself and as such the node may
+elect to not support this message. The text response must be less than
+.Dv NG_TEXTRESPONSE
+bytes in length (presently 1024). This can be used to return general
+status information in human readable form.
+.El
+.Sh Metadata
+Data moving through the
+.Nm
+system can be accompanied by meta-data that describes some
+aspect of that data. The form of the meta-data is a fixed header,
+which contains enough information for most uses, and can optionally 
+be suplemented by trailing
+.Em option
+structures, which contain a 
+.Em cookie
+(see the section on control messages), an identifier, a length and optional
+data. If a node does not recognize the cookie associated with an option,
+it should ignore that option.
+.Pp
+Meta data might include such things as priority, discard eligibility,
+or special processing requirements. It might also mark a packet for
+debug status, etc. The use of meta-data is still experimental.
+.Sh INITIALIZATION
+The base
+.Nm
+code may either be statically compiled
+into the kernel or else loaded dynamically as a KLD via
+.Xr kldload 8 .
+In the former case, include
+.Bd -literal -offset 4n -compact
+
+   options NETGRAPH
+
+.Ed
+in your kernel configuration file. You may also include selected
+node types in the kernel compilation, for example:
+.Bd -literal -offset 4n -compact
+
+   options NETGRAPH
+   options NETGRAPH_SOCKET
+   options NETGRAPH_ECHO
+
+.Ed
+.Pp
+Once the
+.Nm
+subsystem is loaded, individual node types may be loaded at any time
+as KLD modules via
+.Xr kldload 8 .
+Moreover,
+.Nm
+knows how to automatically do this; when a request to create a new
+node of unknown type
+.Em type
+is made,
+.Nm
+will attempt to load the KLD module
+.Dv ng_type.ko .
+.Pp
+Types can also be installed at boot time, as certain device drivers
+may want to export each instance of the device as a netgraph node.
+.Pp
+In general, new types can be installed at any time from within the
+kernel by calling
+.Dv ng_newtype() ,
+supplying a pointer to the type's
+.Dv struct ng_type
+structure.
+.Pp
+The
+.Dv "NETGRAPH_INIT()"
+macro automates this process by using a linker set.
+.Sh EXISTING NODE TYPES
+Several node types currently exist. Each is fully documented
+in its own man page:
+.Bl -tag -width xxx
+.It SOCKET
+The socket type implements two new sockets in the new protocol domain
+.Dv PF_NETGRAPH .
+The new sockets protocols are
+.Dv NG_DATA
+and
+.Dv NG_CONTROL ,
+both of type
+.Dv SOCK_DGRAM .
+Typically one of each is associated with a socket node.
+When both sockets have closed, the node will shut down. The
+.Dv NG_DATA
+socket is used for sending and receiving data, while the
+.Dv NG_CONTROL
+socket is used for sending and receiving control messages.
+Data and control messages are passed using the
+.Xr sendto 2
+and
+.Xr recvfrom 2
+calls, using a
+.Dv struct sockaddr_ng
+socket address.
+.Pp
+.It HOLE
+Responds only to generic messages and is a ``black hole'' for data,
+Useful for testing. Always accepts new hooks.
+.Pp
+.It ECHO
+Responds only to generic messages and always echoes data back through the
+hook from which it arrived. Returns any non generic messages as their
+own response. Useful for testing.  Always accepts new hooks.
+.Pp
+.It TEE
+This node is useful for ``snooping.'' It has 4 hooks:
+.Dv left ,
+.Dv right ,
+.Dv left2right ,
+and
+.Dv right2left .
+Data entering from the right is passed to the left and duplicated on
+.Dv right2left,
+and data entering from the left is passed to the right and
+duplicated on
+.Dv left2right .
+Data entering from
+.Dv left2right
+is sent to the right and data from
+.Dv right2left
+to left. 
+.Pp
+.It RFC1490 MUX
+Encapsulates/de-encapsulates frames encoded according to RFC 1490.
+Has a hook for the encapsulated packets (``downstream'') and one hook
+for each protocol (i.e., IP, PPP, etc.).
+.Pp
+.It FRAME RELAY MUX
+Encapsulates/de-encapsulates Frame Relay frames.
+Has a hook for the encapsulated packets (``downstream'') and one hook
+for each DLCI.
+.Pp
+.It FRAME RELAY LMI
+Automatically handles frame relay
+``LMI'' (link management interface) operations and packets.
+Automatically probes and detects whch of several LMI standards
+is in use at the exchange.
+.Pp
+.It TTY
+This node is also a line discipline. It simply converts between mbuf
+frames and sequential serial data, allowing a tty to appear as a netgraph
+node. It has a programmable ``hotkey'' character.
+.Pp
+.It ASYNC
+This node encapsulates and de-encapsulates asynchronous frames
+according to RFC 1662. This is used in conjunction with the TTY node
+type for supporting PPP links over asynchronous serial lines.
+.Pp
+.It INTERFACE
+This node is also a system networking interface. It has hooks representing
+each protocol family (IP, AppleTalk, IPX, etc.) and appears in the output of
+.Xr ifconfig 8 .
+The interfaces are named
+.Em ng0 ,
+.Em ng1 ,
+etc.
+.El
+.Sh NOTES
+Whether a named node exists can be checked by trying to send a control mesage
+to it (e.g.,
+.Dv NGM_NODEINFO
+).
+If it does not exist,
+.Er ENOENT
+will be returned.
+.Pp
+All data messages are mbuf chains with the M_PKTHDR flag set.
+.Pp
+Nodes are responsible for freeing what they allocate.
+There are three exceptions:
+.Bl -tag -width xxxx
+.It 1
+Mbufs sent across a data link are never to be freed by the sender. 
+.It 2
+Any meta-data information travelling with the data has the same restriction.
+It might be freed by any node the data passes through, and a
+.Dv NULL
+passed onwards, but the caller will never free it.
+Two macros
+.Dv "NG_FREE_META(meta)"
+and
+.Dv "NG_FREE_DATA(m, meta)"
+should be used if possible to free data and meta data (see
+.Dv netgraph.h ")."
+.It 3
+Messages sent using
+.Dv ng_send_message()
+are freed by the callee. As in the case above, the addresses
+associated with the message are freed by whatever allocated them so the 
+recipient should copy them if it wants to keep that information.
+.El
+.Sh FILES
+.Bl -tag -width xxxxx -compact
+.It Pa /sys/netgraph/netgraph.h
+Definitions for use soley within the kernel by
+.Nm
+nodes.
+.It Pa /sys/netgraph/ng_message.h
+Definitions needed by any file that needs to deal with 
+.Nm 
+messages.
+.It Pa /sys/netgraph/ng_socket.h
+Definitions needed to use 
+.Nm
+socket type nodes.
+.It Pa /sys/netgraph/ng_{type}.h
+Definitions needed to use 
+.Nm
+{type}
+nodes, including the type cookie definition.
+.It Pa /modules/netgraph.ko
+Netgraph subsystem loadable KLD module.
+.It Pa /modules/ng_{type}.ko
+Loadable KLD module for node type {type}.
+.El
+.Sh USER MODE SUPPORT
+There is a library for supporting user-mode programs that wish
+to interact with the netgraph system. See
+.Xr netgraph 3
+for details.
+.Pp
+Two user-mode support programs,
+.Xr ngctl 8
+and
+.Xr nghook 8 ,
+are available to assist manual configuration and debugging.
+.Pp
+There are a few useful techniques for debugging new node types.
+First, implementing new node types in user-mode first
+makes debugging easier.
+The
+.Em tee
+node type is also useful for debugging, especially in conjunction with
+.Xr ngctl 8
+and
+.Xr nghook 8 .
+.Sh SEE ALSO
+.Xr socket 2 ,
+.Xr netgraph 3 ,
+.Xr ngctl 8 ,
+.Xr nghook 8 ,
+.Xr ng_async 8 .
+.Xr ng_cisco 8 .
+.Xr ng_echo 8 .
+.Xr ng_frame_relay 8 .
+.Xr ng_hole 8 .
+.Xr ng_iface 8 .
+.Xr ng_lmi 8 .
+.Xr ng_rfc1490 8 .
+.Xr ng_socket 8 .
+.Xr ng_tee 8 .
+.Xr ng_tty 8 .
+.Xr ng_UI 8 .
+.Xr ng_{type} 8 .
+.Sh HISTORY
+The
+.Nm
+system was designed and first implemented at Whistle Communications, Inc.
+in a version FreeBSD 2.2 customized for the Whistle InterJet.
+.Sh AUTHORS
+Julian Elischer <julian@whistle.com>, with contributions by
+Archie Cobbs <archie@whistle.com>.
diff --git a/share/man/man4/ng_UI.4 b/share/man/man4/ng_UI.4
new file mode 100644
index 0000000..f432fc4
--- /dev/null
+++ b/share/man/man4/ng_UI.4
@@ -0,0 +1,86 @@
+.\" Copyright (c) 1996-1999 Whistle Communications, Inc.
+.\" All rights reserved.
+.\" 
+.\" Subject to the following obligations and disclaimer of warranty, use and
+.\" redistribution of this software, in source or object code forms, with or
+.\" without modifications are expressly permitted by Whistle Communications;
+.\" provided, however, that:
+.\" 1. Any and all reproductions of the source or object code must include the
+.\"    copyright notice above and the following disclaimer of warranties; and
+.\" 2. No rights are granted, in any manner or form, to use Whistle
+.\"    Communications, Inc. trademarks, including the mark "WHISTLE
+.\"    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
+.\"    such appears in the above copyright notice or in the software.
+.\" 
+.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
+.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
+.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
+.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
+.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
+.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
+.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
+.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
+.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
+.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
+.\" OF SUCH DAMAGE.
+.\" 
+.\" Author: Archie Cobbs <archie@whistle.com>
+.\"
+.\" $FreeBSD$
+.\" $Whistle: ng_UI.8,v 1.4 1999/01/25 02:37:56 archie Exp $
+.\"
+.Dd January 19, 1999
+.Dt NG_UI 8
+.Os FreeBSD 3
+.Sh NAME
+.Nm ng_UI
+.Nd UI netgraph node type
+.Sh SYNOPSIS
+.Fd #include <netgraph/ng_UI.h>
+.Sh DESCRIPTION
+The
+.Nm UI
+node type has two hooks,
+.Dv upstream
+and
+.Dv downstream .
+Packets received on
+.Dv downstream
+must have 0x03 (indicating unnumbered information) as their first byte;
+if not the packet is dropped. This byte is then stripped and the
+remainder of the packet sent out on
+.Dv upstream .
+.Pp
+Conversely, packets received on
+.Dv upstream
+will have a 0x03 byte prepended to them before being forwarded out on the
+.Dv downstream
+hook.
+.Sh HOOKS
+This node type supports the following hooks:
+.Pp
+.Bl -tag -width foobar
+.It Dv downstream
+Downstream connection. Packets on this side of the node have a 0x03 as
+their first byte.
+.It Dv upstream
+Upstream connection. Packets on this side of the node have the
+initial 0x03 byte stripped off.
+.El
+.Sh CONTROL MESSAGES
+This node type supports only the generic control messages.
+.Sh SHUTDOWN
+This node shuts down upon receipt of a
+.Dv NGM_SHUTDOWN
+control message, or when both hooks have been disconnected.
+.Sh SEE ALSO
+.Xr netgraph 4 ,
+.Xr ngctl 8 .
+.Sh AUTHOR
+Julian Elischer <julian@whistle.com>
diff --git a/share/man/man4/ng_async.4 b/share/man/man4/ng_async.4
new file mode 100644
index 0000000..cddaa1b6
--- /dev/null
+++ b/share/man/man4/ng_async.4
@@ -0,0 +1,160 @@
+.\" Copyright (c) 1996-1999 Whistle Communications, Inc.
+.\" All rights reserved.
+.\" 
+.\" Subject to the following obligations and disclaimer of warranty, use and
+.\" redistribution of this software, in source or object code forms, with or
+.\" without modifications are expressly permitted by Whistle Communications;
+.\" provided, however, that:
+.\" 1. Any and all reproductions of the source or object code must include the
+.\"    copyright notice above and the following disclaimer of warranties; and
+.\" 2. No rights are granted, in any manner or form, to use Whistle
+.\"    Communications, Inc. trademarks, including the mark "WHISTLE
+.\"    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
+.\"    such appears in the above copyright notice or in the software.
+.\" 
+.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
+.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
+.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
+.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
+.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
+.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
+.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
+.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
+.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
+.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
+.\" OF SUCH DAMAGE.
+.\" 
+.\" Author: Archie Cobbs <archie@whistle.com>
+.\"
+.\" $FreeBSD$
+.\" $Whistle: ng_async.8,v 1.6 1999/01/25 23:46:25 archie Exp $
+.\"
+.Dd January 19, 1999
+.Dt NG_ASYNC 8
+.Os FreeBSD 3
+.Sh NAME
+.Nm ng_async
+.Nd asynchronous framing netgraph node type
+.Sh SYNOPSIS
+.Fd #include <netgraph/ng_async.h>
+.Sh DESCRIPTION
+The
+.Nm async
+node type performs conversion between synchronous frames and
+asynchronous frames, as defined for the PPP protocol in RFC 1662.
+Asynchronous framing uses flag bytes and octet-stuffing
+to simulate a frame oriented connection over an octet-oriented
+asynchronous line.
+.Pp
+The node trasmits and receives asynchronous data on the
+.Dv async
+hook.  Incoming data mbuf boundaries are ignored, while
+outgoing data is sent as a complete frame at a time.
+.Pp
+There are two synchronous hooks,
+.Dv sync
+and
+.Dv sync2 .
+For both hooks, received packets are encoded as asynchronous frames
+and sent out on
+.Dv async .
+Hook
+.Dv sync2
+differs from
+.Dv sync
+only in that any configured address and control field compression
+and/or control character escaping is disabled when the frame is encoded.
+This is useful for transmitting PPP LCP packets, which are always sent
+this way.
+.Pp
+This node supports ``flag sharing'' for packets transmitted on
+.Dv async .
+This is an optimization where the trailing flag byte
+of one frame is shared with the opening flag byte of the next.
+Flag sharing between frames is disabled after one second of transmit
+idle time.
+.Sh HOOKS
+This node type supports the following hooks:
+.Pp
+.Bl -tag -width foobar
+.It Dv async
+Asynchronous connection.
+Typically this hook would be connected to a
+.Xr ng_tty 8
+node, which handles transmission of serial data over a tty device.
+.It Dv sync
+Synchronous connection. This hook sends and receives synchronous frames.
+For PPP, these frames contain no address, control, or checksum fields;
+each frame begins with the PPP protocol number. Typically this hook would
+be connected to the
+.Dv downstream
+hook of a
+.Xr ng_ppp 8
+type node.
+.El
+.Sh CONTROL MESSAGES
+This node type supports the generic control messages, plus the following:
+.Bl -tag -width foo
+.It Dv NGM_ASYNC_CMD_GET_STATS
+This command returns a
+.Dv "struct ng_async_stat"
+containing node statistics for packet, octet, and error counts.
+.It Dv NGM_ASYNC_CMD_CLR_STATS
+Clears the node statistics.
+.It Dv NGM_ASYNC_CMD_SET_CONFIG
+Sets the node configuration, which is described by a
+.Dv "struct ng_async_cfg" :
+.Bd -literal -offset 4n
+struct ng_async_cfg {
+  u_char    enabled;  /* Turn encoding on/off */
+  u_char    acfcomp;  /* Address/control field comp. */
+  u_int16_t amru;     /* Max receive async frame len */
+  u_int16_t smru;     /* Max receive sync frame len */
+  u_int32_t accm;     /* ACCM encoding */
+};
+.Ed
+.Pp
+The
+.Dv enabled
+field enables or disables all encoding/decoding functions (default disabled).
+When disabled, the node operates in simple ``pass through'' mode.  Setting
+.Dv acfcomp
+enables address and control field compression on transmission (for packets
+received on the
+.Dv sync
+hook only; default off).
+.Dv amru
+and
+.Dv smru
+are the asynchronous and synchronous MRU (maximum receive unit) values,
+respectively. These both default to 1600; note that the async MRU
+applies to the incoming frame length after asynchronous decoding.
+Finally,
+.Dv accm
+is the asynchronous character control map, which controls the escaping
+of characters 0x00 thorough 0x1f (default 0xffffffff).
+.It Dv NGM_ASYNC_CMD_GET_CONFIG
+This command returns the current configuration structure.
+.El
+.Sh SHUTDOWN
+This node shuts down upon receipt of a
+.Dv NGM_SHUTDOWN
+control message, or when all hooks have been disconnected.
+.Sh SEE ALSO
+.Xr netgraph 4 ,
+.Xr ng_ppp 8 ,
+.Xr ng_tty 8 ,
+.Xr ngctl 8 .
+.Rs
+.%A W. Simpson
+.%T "PPP in HDLC-link Framing"
+.%O RFC 1662
+.Re
+.Sh AUTHOR
+Archie Cobbs <archie@whistle.com>
diff --git a/share/man/man4/ng_cisco.4 b/share/man/man4/ng_cisco.4
new file mode 100644
index 0000000..30523f8
--- /dev/null
+++ b/share/man/man4/ng_cisco.4
@@ -0,0 +1,159 @@
+.\" Copyright (c) 1996-1999 Whistle Communications, Inc.
+.\" All rights reserved.
+.\" 
+.\" Subject to the following obligations and disclaimer of warranty, use and
+.\" redistribution of this software, in source or object code forms, with or
+.\" without modifications are expressly permitted by Whistle Communications;
+.\" provided, however, that:
+.\" 1. Any and all reproductions of the source or object code must include the
+.\"    copyright notice above and the following disclaimer of warranties; and
+.\" 2. No rights are granted, in any manner or form, to use Whistle
+.\"    Communications, Inc. trademarks, including the mark "WHISTLE
+.\"    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
+.\"    such appears in the above copyright notice or in the software.
+.\" 
+.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
+.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
+.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
+.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
+.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
+.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
+.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
+.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
+.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
+.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
+.\" OF SUCH DAMAGE.
+.\" 
+.\" Author: Archie Cobbs <archie@whistle.com>
+.\"
+.\" $FreeBSD$
+.\" $Whistle: ng_cisco.8,v 1.5 1999/01/25 23:46:26 archie Exp $
+.\"
+.Dd January 19, 1999
+.Dt NG_CISCO 8
+.Os FreeBSD 3
+.Sh NAME
+.Nm ng_cisco
+.Nd Cisco HDLC protocol netgraph node type
+.Sh SYNOPSIS
+.Fd #include <netgraph/ng_cisco.h>
+.Sh DESCRIPTION
+The
+.Nm cisco
+node type performs encapsulation and de-encapsulation of packets
+using the Cisco HDLC protocol. This is a fairly simple
+protocol for the transmission of packets across
+high speed synchronous lines. Each packet is prepended with
+an Ethertype, indicating the protocol. There is also a
+``keep alive'' and an ``inquire'' capability.
+.Pp
+The
+.Dv downstream
+hook should connect to the synchronous line. On the other side
+of the node are the
+.Dv inet ,
+.Dv atalk ,
+and
+.Dv ipx
+hooks, which transmit and receive raw IP, AppleTalk, and IPX packets,
+respectively.  Typically these hooks would connect to the corresponding
+hooks on an
+.Xr ng_iface 8
+type node.
+.Sh IP Configuration
+In order to function properly for IP traffic, the node must be informed
+of the local IP address and netmask setting.  This is because the protocol
+includes an ``inquire'' packet which we must be prepared to answer.
+There are two ways to acomplish this, manually and automatically.
+.Pp
+Whenever such an inquire packet is received, the node sends a
+.Dv NGM_CISCO_GET_IPADDR
+control message to the peer node connected to the
+.Dv inet
+hook (if any).
+If the peer responds, then that response is used. This is the automatic method.
+.Pp
+If the peer does not respond, the node falls back on its cached value
+for the IP address and netmask. This cached value can be set at any time
+with a
+.Dv NGM_CISCO_SET_IPADDR
+message, and this is the manual method.
+.Pp
+If the
+.Dv inet
+hook is connected to the
+.Dv inet
+hook of an
+.Xr ng_iface 8
+node, as is usually the case, then configuration is automatic as the 
+.Xr ng_iface 8
+understands the
+.Dv NGM_CISCO_GET_IPADDR
+message.
+.Sh HOOKS
+This node type supports the following hooks:
+.Pp
+.Bl -tag -width foobarbazio
+.It Dv downstream
+The connection to the synchronous line.
+.It Dv inet
+IP hook.
+.It Dv atalk
+AppleTalk hook.
+.It Dv ipx
+IPX hook
+.El
+.Sh CONTROL MESSAGES
+This node type supports the generic control messages, plus the following:
+.Bl -tag -width foo
+.It Dv NGM_CISCO_SET_IPADDR
+This command takes an array of two
+.Dv "struct in_addr"
+arguments. The first is the IP address of the corresponding interface
+and the second is the netmask.
+.It Dv NGM_CISCO_GET_IPADDR
+This command returns the IP configuration in the same format used by
+.Dv NGM_CISCO_SET_IPADDR .
+This command is also
+.Em sent
+by this node type to the
+.Dv inet
+peer whenever an IP address inquiry packet is received.
+.It Dv NGM_CISCO_GET_STATUS
+Returns a
+.Dv "struct ngciscostat" :
+.Bd -literal -offset 4n
+struct ngciscostat {
+  u_int32_t   seq_retries;       /* # unack'd retries */
+  u_int32_t   keepalive_period;  /* in seconds */
+};
+.Ed
+.El
+.Sh SHUTDOWN
+This node shuts down upon receipt of a
+.Dv NGM_SHUTDOWN
+control message, or when all hooks have been disconnected.
+.Sh BUGS
+Not all of the functionality has been implemented. For example,
+the node does not support querying the remote end for its IP address
+and netmask.
+.Sh SEE ALSO
+.Xr netgraph 4 ,
+.Xr ng_iface 8 ,
+.Xr ngctl 8 .
+.Rs
+.%A D. Perkins
+.%T "Requirements for an Internet Standard Point-to-Point Protocol"
+.%O RFC 1547
+.Re
+.Sh LEGAL
+Cisco is a trademark of Cisco Systems, Inc.
+.Sh AUTHORS
+Julian Elisher <julian@whistle.com>,
+Archie Cobbs <archie@whistle.com>
diff --git a/share/man/man4/ng_echo.4 b/share/man/man4/ng_echo.4
new file mode 100644
index 0000000..33ca729
--- /dev/null
+++ b/share/man/man4/ng_echo.4
@@ -0,0 +1,67 @@
+.\" Copyright (c) 1996-1999 Whistle Communications, Inc.
+.\" All rights reserved.
+.\" 
+.\" Subject to the following obligations and disclaimer of warranty, use and
+.\" redistribution of this software, in source or object code forms, with or
+.\" without modifications are expressly permitted by Whistle Communications;
+.\" provided, however, that:
+.\" 1. Any and all reproductions of the source or object code must include the
+.\"    copyright notice above and the following disclaimer of warranties; and
+.\" 2. No rights are granted, in any manner or form, to use Whistle
+.\"    Communications, Inc. trademarks, including the mark "WHISTLE
+.\"    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
+.\"    such appears in the above copyright notice or in the software.
+.\" 
+.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
+.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
+.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
+.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
+.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
+.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
+.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
+.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
+.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
+.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
+.\" OF SUCH DAMAGE.
+.\" 
+.\" Author: Archie Cobbs <archie@whistle.com>
+.\"
+.\" $FreeBSD$
+.\" $Whistle: ng_echo.8,v 1.4 1999/01/25 23:46:26 archie Exp $
+.\"
+.Dd January 19, 1999
+.Dt NG_ECHO 8
+.Os FreeBSD 3
+.Sh NAME
+.Nm ng_echo
+.Nd netgraph echo node type
+.Sh SYNOPSIS
+.Fd #include <netgraph/ng_echo.h>
+.Sh DESCRIPTION
+The
+.Nm echo
+node type reflects all data and control messages back to the sender.
+This node type is used for testing and debugging.
+.Sh HOOKS
+.Nm Echo
+nodes accept any request to connect, regardless of the hook name,
+as long as the name is unique.
+.Sh CONTROL MESSAGES
+This node type supports only the generic control messages.
+Any other control messages are reflected back to the sender.
+.Sh SHUTDOWN
+This node shuts down upon receipt of a
+.Dv NGM_SHUTDOWN
+control message, or when all hooks have been disconnected.
+.Sh SEE ALSO
+.Xr netgraph 4 ,
+.Xr ng_hole 8 ,
+.Xr ngctl 8 .
+.Sh AUTHOR
+Julian Elisher <julian@whistle.com>
diff --git a/share/man/man4/ng_frame_relay.4 b/share/man/man4/ng_frame_relay.4
new file mode 100644
index 0000000..790676d
--- /dev/null
+++ b/share/man/man4/ng_frame_relay.4
@@ -0,0 +1,93 @@
+.\" Copyright (c) 1996-1999 Whistle Communications, Inc.
+.\" All rights reserved.
+.\" 
+.\" Subject to the following obligations and disclaimer of warranty, use and
+.\" redistribution of this software, in source or object code forms, with or
+.\" without modifications are expressly permitted by Whistle Communications;
+.\" provided, however, that:
+.\" 1. Any and all reproductions of the source or object code must include the
+.\"    copyright notice above and the following disclaimer of warranties; and
+.\" 2. No rights are granted, in any manner or form, to use Whistle
+.\"    Communications, Inc. trademarks, including the mark "WHISTLE
+.\"    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
+.\"    such appears in the above copyright notice or in the software.
+.\" 
+.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
+.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
+.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
+.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
+.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
+.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
+.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
+.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
+.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
+.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
+.\" OF SUCH DAMAGE.
+.\" 
+.\" Author: Archie Cobbs <archie@whistle.com>
+.\"
+.\" $FreeBSD$
+.\" $Whistle: ng_frame_relay.8,v 1.4 1999/01/25 23:46:26 archie Exp $
+.\"
+.Dd January 19, 1999
+.Dt NG_FRAME_RELAY 8
+.Os FreeBSD 3
+.Sh NAME
+.Nm ng_frame_relay
+.Nd Frame relay netgraph node type
+.Sh SYNOPSIS
+.Fd #include <netgraph/ng_frame_relay.h>
+.Sh DESCRIPTION
+The
+.Nm frame_relay
+node type performs encapsulation, de-encapsulation, and multiplexing
+of packets using the frame relay protocol. It supports up to 1024 DLCI's.
+The LMI protocol is handled by a separate node type (see
+.Xr ng_lmi 8 ).
+.Pp
+The
+.Dv downstream
+hook should be connected to the synchronous line, i.e., the switch.
+Then hooks
+.Dv dlci0 ,
+.Dv dlci1 ,
+through
+.Dv dlci1023
+are available to connect to each of the DLCI channels.
+.Sh HOOKS
+This node type supports the following hooks:
+.Pp
+.Bl -tag -width foobar
+.It Dv downstream
+The connection to the synchronous line.
+.It Dv dlciX
+Here X is a decimal number from 0 to 1023. This hook corresponds
+to the DLCI X frame relay virtual channel.
+.El
+.Sh CONTROL MESSAGES
+This node type supports only the generic control messages.
+.Sh SHUTDOWN
+This node shuts down upon receipt of a
+.Dv NGM_SHUTDOWN
+control message, or when all hooks have been disconnected.
+.Sh BUGS
+Technically, frames on DLCI X should not be transmitted to the switch
+until the LMI protocol entity on both ends has configured DLCI X as active.
+The
+.Nm frame_relay
+node type ignores this restriction, and will always pass data received
+on a DLCI hook to
+.Dv downstream .
+Instead, it should query the LMI node first.
+.Sh SEE ALSO
+.Xr netgraph 4 ,
+.Xr ng_lmi 8 ,
+.Xr ngctl 8 .
+.Sh AUTHOR
+Julian Elisher <julian@whistle.com>
diff --git a/share/man/man4/ng_hole.4 b/share/man/man4/ng_hole.4
new file mode 100644
index 0000000..4d34eb5
--- /dev/null
+++ b/share/man/man4/ng_hole.4
@@ -0,0 +1,67 @@
+.\" Copyright (c) 1996-1999 Whistle Communications, Inc.
+.\" All rights reserved.
+.\" 
+.\" Subject to the following obligations and disclaimer of warranty, use and
+.\" redistribution of this software, in source or object code forms, with or
+.\" without modifications are expressly permitted by Whistle Communications;
+.\" provided, however, that:
+.\" 1. Any and all reproductions of the source or object code must include the
+.\"    copyright notice above and the following disclaimer of warranties; and
+.\" 2. No rights are granted, in any manner or form, to use Whistle
+.\"    Communications, Inc. trademarks, including the mark "WHISTLE
+.\"    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
+.\"    such appears in the above copyright notice or in the software.
+.\" 
+.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
+.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
+.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
+.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
+.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
+.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
+.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
+.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
+.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
+.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
+.\" OF SUCH DAMAGE.
+.\" 
+.\" Author: Archie Cobbs <archie@whistle.com>
+.\"
+.\" $FreeBSD$
+.\" $Whistle: ng_hole.8,v 1.4 1999/01/25 23:46:26 archie Exp $
+.\"
+.Dd January 19, 1999
+.Dt NG_HOLE 8
+.Os FreeBSD 3
+.Sh NAME
+.Nm ng_hole
+.Nd netgraph discard node type
+.Sh SYNOPSIS
+.Fd #include <netgraph/ng_hole.h>
+.Sh DESCRIPTION
+The
+.Nm hole
+node type silently discards all data and control messages it receives.
+This type is used for testing and debugging.
+.Sh HOOKS
+.Nm Hole
+nodes accept any request to connect, regardless of the hook name,
+as long as the name is unique.
+.Sh CONTROL MESSAGES
+This node type supports only the generic control messages.
+Other control messages are silently discarded.
+.Sh SHUTDOWN
+This node shuts down upon receipt of a
+.Dv NGM_SHUTDOWN
+control message, or when all hooks have been disconnected.
+.Sh SEE ALSO
+.Xr netgraph 4 ,
+.Xr ng_echo 8 ,
+.Xr ngctl 8 .
+.Sh AUTHOR
+Julian Elisher <julian@whistle.com>
diff --git a/share/man/man4/ng_iface.4 b/share/man/man4/ng_iface.4
new file mode 100644
index 0000000..77167e6
--- /dev/null
+++ b/share/man/man4/ng_iface.4
@@ -0,0 +1,126 @@
+.\" Copyright (c) 1996-1999 Whistle Communications, Inc.
+.\" All rights reserved.
+.\" 
+.\" Subject to the following obligations and disclaimer of warranty, use and
+.\" redistribution of this software, in source or object code forms, with or
+.\" without modifications are expressly permitted by Whistle Communications;
+.\" provided, however, that:
+.\" 1. Any and all reproductions of the source or object code must include the
+.\"    copyright notice above and the following disclaimer of warranties; and
+.\" 2. No rights are granted, in any manner or form, to use Whistle
+.\"    Communications, Inc. trademarks, including the mark "WHISTLE
+.\"    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
+.\"    such appears in the above copyright notice or in the software.
+.\" 
+.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
+.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
+.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
+.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
+.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
+.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
+.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
+.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
+.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
+.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
+.\" OF SUCH DAMAGE.
+.\" 
+.\" Author: Archie Cobbs <archie@whistle.com>
+.\"
+.\" $FreeBSD$
+.\" $Whistle: ng_iface.8,v 1.5 1999/01/25 23:46:26 archie Exp $
+.\"
+.Dd January 19, 1999
+.Dt NG_IFACE 8
+.Os FreeBSD 3
+.Sh NAME
+.Nm ng_iface
+.Nd interface netgraph node type
+.Sh SYNOPSIS
+.Fd #include <netgraph/ng_iface.h>
+.Sh DESCRIPTION
+An
+.Nm iface
+node is both a netgraph node and a system networking interface.  When an
+.Nm iface
+node is created, a new point-to-point interface appears which is accessible via
+.Xr ifconfig 8 .
+The new interfaces are named
+.Dv ng0 ,
+.Dv ng1 ,
+etc.  The node is assigned the same name as its interface, unless the name
+already exists, in which case the node remains unnamed.
+.Pp
+.Nm Iface
+nodes have a single hook corresponding to each supported protocol.
+Packets transmitted via the interface flow out the corresponding
+protocol-specific hook.
+Similarly, packets received on a hook appear on the interface as 
+packets received in the corresponding protocol.
+.Pp
+The currently supported protocols are IP, IPX, AppleTalk, and NS.
+In the KLD module, only support for IP is compiled in by default.
+.Pp
+.Nm Iface
+nodes support the Berkeley Packet Filter (BPF). 
+In the KLD module, this support is disabled by default.
+.Sh HOOKS
+This node type supports the following hooks:
+.Pp
+.Bl -tag -width foobar
+.It Dv inet
+Transmission and reception of IP packets.
+.It Dv ipx
+Transmission and reception of IPX packets.
+.It Dv atalk
+Transmission and reception of AppleTalk packets.
+.It Dv ns
+Transmission and reception of NS packets.
+.El
+.Sh CONTROL MESSAGES
+This node type supports the generic control messages, plus the following:
+.Bl -tag -width foo
+.It Dv NGM_IFACE_GET_IFNAME
+Returns the name of the interface corresponding to this node in a
+.Dv "struct ng_iface_ifname" :
+.Bd -literal -offset 4n
+struct ng_iface_ifname {
+  char  ngif_name[NG_IFACE_IFACE_NAME_MAX + 1];
+};
+.Ed
+.It Dv NGM_IFACE_GET_IFADDRS
+Returns the list of addresses associated with this interface.
+The list is returned in the same format as the
+.Dv SIOCGIFCONF
+ioctl().
+.It Dv NGM_CISCO_GET_IPADDR
+This message is defined by the
+.Xr ng_cisco 8
+node type; see
+.Xr ng_cisco 8
+for a description.
+.El
+.Sh SHUTDOWN
+Because it is currenly not possible to remove a system networking
+interface in FreeBSD,
+.Nm iface
+nodes are
+.Em persistent.
+That is, once created they are never destroyed.
+The receipt of a
+.Dv NGM_SHUTDOWN
+control message disconnects all hooks but does not remove the node.
+.Sh SEE ALSO
+.Xr netgraph 4 ,
+.Xr bpf 4 ,
+.Xr ng_cisco 8 ,
+.Xr ng_rfc1490 8 ,
+.Xr ngctl 8 ,
+.Xr ifconfig 8 .
+.Sh AUTHOR
+Archie Cobbs <archie@whistle.com>
diff --git a/share/man/man4/ng_lmi.4 b/share/man/man4/ng_lmi.4
new file mode 100644
index 0000000..fc0ba24
--- /dev/null
+++ b/share/man/man4/ng_lmi.4
@@ -0,0 +1,130 @@
+.\" Copyright (c) 1996-1999 Whistle Communications, Inc.
+.\" All rights reserved.
+.\" 
+.\" Subject to the following obligations and disclaimer of warranty, use and
+.\" redistribution of this software, in source or object code forms, with or
+.\" without modifications are expressly permitted by Whistle Communications;
+.\" provided, however, that:
+.\" 1. Any and all reproductions of the source or object code must include the
+.\"    copyright notice above and the following disclaimer of warranties; and
+.\" 2. No rights are granted, in any manner or form, to use Whistle
+.\"    Communications, Inc. trademarks, including the mark "WHISTLE
+.\"    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
+.\"    such appears in the above copyright notice or in the software.
+.\" 
+.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
+.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
+.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
+.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
+.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
+.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
+.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
+.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
+.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
+.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
+.\" OF SUCH DAMAGE.
+.\" 
+.\" Author: Archie Cobbs <archie@whistle.com>
+.\"
+.\" $FreeBSD$
+.\" $Whistle: ng_lmi.8,v 1.4 1999/01/25 23:46:27 archie Exp $
+.\"
+.Dd January 19, 1999
+.Dt NG_LMI 8
+.Os FreeBSD 3
+.Sh NAME
+.Nm ng_lmi
+.Nd Frame relay LMI protocol netgraph node type
+.Sh SYNOPSIS
+.Fd #include <netgraph/ng_lmi.h>
+.Sh DESCRIPTION
+The
+.Nm lmi
+node type performs the frame relay LMI protocol. It supports
+the ITU Annex A, ANSI Annex D, and Group-of-four LMI types.
+It also supports auto-detection of the LMI type.
+.Pp
+To enable a specific LMI type, connect the corresponding hook (
+.Dv annexA ,
+.Dv annexD ,
+or
+.Dv group4 ")"
+to DLCI 0 or 1023 of a
+.Xr ng_frame_relay 8
+node.
+Typically, Annex A and Annex D live on DLCI 0 while Group-of-four
+lives on DLCI 1023.
+.Pp
+To enable LMI type auto-detection, connect the
+.Dv auto0
+hook to DLCI 0 and the
+.Dv auto1023
+hook to DLCI 1023. The node will attempt to automatically determine
+which LMI type is running at the switch, and go into that mode.
+.Pp
+Only one fixed LMI type, or auto-detection, can be active at any given time.
+.Pp
+The
+.Dv NGM_LMI_GET_STATUS
+control message can be used at any time to query the current status
+of the LMI protocol and each DLCI channel. This node also supports the
+.Dv NGM_TEXT_STATUS
+control message.
+.Sh HOOKS
+This node type supports the following hooks:
+.Pp
+.Bl -tag -width foobarbaz
+.It Dv annexA
+ITU Annex A LMI hook.
+.It Dv annexD
+ANSI Annex D LMI hook.
+.It Dv group4
+Group-of-four LMI hook.
+.It Dv auto0
+Auto-detection hook for DLCI 0.
+.It Dv auto1023
+Auto-detection hook for DLCI 1023.
+.El
+.Sh CONTROL MESSAGES
+This node type supports the generic control messages, plus the following:
+.Bl -tag -width foo
+.It Dv NGM_LMI_GET_STATUS
+This command returns status information in a
+.Dv "struct nglmistat" :
+.Bd -literal -offset 4n
+#define NGM_LMI_STAT_ARYSIZE   (1024/8)
+
+struct nglmistat {
+  u_char  proto[12];	/* Active proto (same as hook name) */
+  u_char  hook[12];	/* Active hook */
+  u_char  fixed;	/* If set to fixed LMI mode */
+  u_char  autod;	/* If currently auto-detecting */
+  u_char  seen[NGM_LMI_STAT_ARYSIZE];	/* bitmap DLCIs seen */
+  u_char  up[NGM_LMI_STAT_ARYSIZE];	/* bitmap DLCIs up */
+};
+.Ed
+.It Dv NGM_TEXT_STATUS
+This generic message returns is a human-readable version of the node status.
+.El
+.Sh SHUTDOWN
+This node shuts down upon receipt of a
+.Dv NGM_SHUTDOWN
+control message, or when all hooks have been disconnected.
+.Sh SEE ALSO
+.Xr netgraph 4 ,
+.Xr ng_frame_relay 8 ,
+.Xr ngctl 8 .
+.Rs
+.%T "ANSI T1.617-1991 Annex D"
+.Re
+.Rs
+.%T "ITU-T Q.933 Digital Subscriber Signalling System No. 1 - Signalling Specification for Frame Mode Basic Call Control, Annex A"
+.Re
+.Sh AUTHOR
+Julian Elisher <julian@whistle.com>
diff --git a/share/man/man4/ng_ppp.4 b/share/man/man4/ng_ppp.4
new file mode 100644
index 0000000..cffa78e
--- /dev/null
+++ b/share/man/man4/ng_ppp.4
@@ -0,0 +1,164 @@
+.\" Copyright (c) 1996-1999 Whistle Communications, Inc.
+.\" All rights reserved.
+.\" 
+.\" Subject to the following obligations and disclaimer of warranty, use and
+.\" redistribution of this software, in source or object code forms, with or
+.\" without modifications are expressly permitted by Whistle Communications;
+.\" provided, however, that:
+.\" 1. Any and all reproductions of the source or object code must include the
+.\"    copyright notice above and the following disclaimer of warranties; and
+.\" 2. No rights are granted, in any manner or form, to use Whistle
+.\"    Communications, Inc. trademarks, including the mark "WHISTLE
+.\"    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
+.\"    such appears in the above copyright notice or in the software.
+.\" 
+.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
+.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
+.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
+.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
+.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
+.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
+.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
+.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
+.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
+.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
+.\" OF SUCH DAMAGE.
+.\" 
+.\" Author: Archie Cobbs <archie@whistle.com>
+.\"
+.\" $FreeBSD$
+.\" $Whistle: ng_ppp.8,v 1.3 1999/01/25 23:46:27 archie Exp $
+.\"
+.Dd January 19, 1999
+.Dt NG_PPP 8
+.Os FreeBSD 3
+.Sh NAME
+.Nm ng_ppp
+.Nd PPP protocol multiplexor negraph node type
+.Sh SYNOPSIS
+.Fd #include <netgraph/ng_ppp.h>
+.Sh DESCRIPTION
+The
+.Nm ppp
+node type performs multiplexing for the PPP protocol. On the
+.Dv downstream
+hook it transmits and receives full PPP frames, which include the
+protocol field, but no address, control or checksum fields.
+On outgoing frames, when protocol compression has been enabled and
+the protocol number is suitable for compression, the protocol field will
+be compressed (i.e., sent as one byte instead of two).
+Either compressed or uncompressed protocol fields are accepted
+on incoming frames.
+.Pp
+For each 16-bit PPP procotol number there is a corresponding ``upstream'' hook.
+Packets on these hooks contain no PPP protocol header.
+The node simply multiplexes between the
+.Dv downstream
+hook and all of the upstream hooks by adding or subtracting the
+PPP protocol field, depending on the direction of flow.
+.Pp
+When a frame is received on
+.Dv downstream ,
+if the corresponding protocol hook is
+not connected, the packet is forwarded to a special upstream hook called
+.Dv bypass .
+This hook is a catch-all for any incoming frames not destined
+for another already connected hook. Packets sent out on the
+.Dv bypass
+hook always have the PPP protcol header prepended as the first
+two bytes (even if the
+original incoming frame was protocol compressed to one byte).
+.Pp
+Any frames received on the
+.Dv bypass
+hook are forwarded to
+.Dv downstream
+without modification.
+.Sh HOOKS
+This node type supports the following hooks:
+.Pp
+.Bl -tag -width foobarbazi
+.It Dv downstream
+Connection to the PPP link layer.
+.It Dv bypass
+Frames that do not correspond to a connected protocol hook;
+the PPP protocol header is included.
+.It Dv 0xNNNN
+Conection to the PPP protocol with 16-bit hex value
+.Dv NNNN .
+No PPP protocol header is included.
+.El
+.Pp
+For convenience, the
+.Nm
+node type defines several hook name aliases for common PPP protocols:
+.Pp
+.Bl -tag -width abcdefgh -compact -offset 4n
+.It Dv lcp
+LCP protocol data (0xc021)
+.It Dv ipcp
+IPCP protocol data (0x8021)
+.It Dv atcp
+ATCP protocol data (0x8029)
+.It Dv ccp
+CCP protocol data (0x80fd)
+.It Dv ecp
+ECP protocol data (0x8053)
+.It Dv ip
+IP protocol data (0x0021)
+.It Dv vjcomp
+Van Jacobsen compressed TCP data (0x002d)
+.It Dv vjuncomp
+Van Jacobsen uncompressed TCP data (0x002f)
+.It Dv mp
+Multi-link protocol data (0x003d)
+.It Dv compd
+Compressed protocol data (0x00fd)
+.It Dv cryptd
+Encrypted protocol data (0x0053)
+.It Dv pap
+PAP authentication protocol data (0xc023)
+.It Dv chap
+CHAP authentication protocol data (0xc223)
+.It Dv lqr
+LQR protocol data (0xc025)
+.El
+.Sh CONTROL MESSAGES
+This node type supports the generic control messages, plus the following:
+.Bl -tag -width foo
+.It Dv NGM_PPP_SET_PROTOCOMP
+This command takes a single integer as argument and enables or disables
+protocol field compression as the value is zero or non-zero.
+Note that only protocols with high order byte equal to
+.Dv 0x00
+are compressible.
+.It Dv NGM_PPP_GET_STATS
+This command returns a
+.Dv "struct ng_ppp_stat"
+containing various node statistics.
+.It Dv NGM_PPP_CLR_STATS
+Clears the node statistics. Statistics are also cleared whenever the
+.Dv downstream
+hook is reconnected.
+.Sh SHUTDOWN
+This node shuts down upon receipt of a
+.Dv NGM_SHUTDOWN
+control message, or when all hooks have been disconnected.
+.Sh SEE ALSO
+.Xr netgraph 4 ,
+.Xr ng_async 8 ,
+.Xr ng_vjc 8 ,
+.Xr ngctl 8 .
+.Rs
+.%A W. Simpson
+.%T "The Point-to-Point Protocol (PPP)"
+.%O RFC 1661
+.Re
+.Sh AUTHOR
+Archie Cobbs <archie@whistle.com>
diff --git a/share/man/man4/ng_pppoe.4 b/share/man/man4/ng_pppoe.4
new file mode 100644
index 0000000..fc0ba24
--- /dev/null
+++ b/share/man/man4/ng_pppoe.4
@@ -0,0 +1,130 @@
+.\" Copyright (c) 1996-1999 Whistle Communications, Inc.
+.\" All rights reserved.
+.\" 
+.\" Subject to the following obligations and disclaimer of warranty, use and
+.\" redistribution of this software, in source or object code forms, with or
+.\" without modifications are expressly permitted by Whistle Communications;
+.\" provided, however, that:
+.\" 1. Any and all reproductions of the source or object code must include the
+.\"    copyright notice above and the following disclaimer of warranties; and
+.\" 2. No rights are granted, in any manner or form, to use Whistle
+.\"    Communications, Inc. trademarks, including the mark "WHISTLE
+.\"    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
+.\"    such appears in the above copyright notice or in the software.
+.\" 
+.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
+.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
+.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
+.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
+.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
+.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
+.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
+.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
+.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
+.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
+.\" OF SUCH DAMAGE.
+.\" 
+.\" Author: Archie Cobbs <archie@whistle.com>
+.\"
+.\" $FreeBSD$
+.\" $Whistle: ng_lmi.8,v 1.4 1999/01/25 23:46:27 archie Exp $
+.\"
+.Dd January 19, 1999
+.Dt NG_LMI 8
+.Os FreeBSD 3
+.Sh NAME
+.Nm ng_lmi
+.Nd Frame relay LMI protocol netgraph node type
+.Sh SYNOPSIS
+.Fd #include <netgraph/ng_lmi.h>
+.Sh DESCRIPTION
+The
+.Nm lmi
+node type performs the frame relay LMI protocol. It supports
+the ITU Annex A, ANSI Annex D, and Group-of-four LMI types.
+It also supports auto-detection of the LMI type.
+.Pp
+To enable a specific LMI type, connect the corresponding hook (
+.Dv annexA ,
+.Dv annexD ,
+or
+.Dv group4 ")"
+to DLCI 0 or 1023 of a
+.Xr ng_frame_relay 8
+node.
+Typically, Annex A and Annex D live on DLCI 0 while Group-of-four
+lives on DLCI 1023.
+.Pp
+To enable LMI type auto-detection, connect the
+.Dv auto0
+hook to DLCI 0 and the
+.Dv auto1023
+hook to DLCI 1023. The node will attempt to automatically determine
+which LMI type is running at the switch, and go into that mode.
+.Pp
+Only one fixed LMI type, or auto-detection, can be active at any given time.
+.Pp
+The
+.Dv NGM_LMI_GET_STATUS
+control message can be used at any time to query the current status
+of the LMI protocol and each DLCI channel. This node also supports the
+.Dv NGM_TEXT_STATUS
+control message.
+.Sh HOOKS
+This node type supports the following hooks:
+.Pp
+.Bl -tag -width foobarbaz
+.It Dv annexA
+ITU Annex A LMI hook.
+.It Dv annexD
+ANSI Annex D LMI hook.
+.It Dv group4
+Group-of-four LMI hook.
+.It Dv auto0
+Auto-detection hook for DLCI 0.
+.It Dv auto1023
+Auto-detection hook for DLCI 1023.
+.El
+.Sh CONTROL MESSAGES
+This node type supports the generic control messages, plus the following:
+.Bl -tag -width foo
+.It Dv NGM_LMI_GET_STATUS
+This command returns status information in a
+.Dv "struct nglmistat" :
+.Bd -literal -offset 4n
+#define NGM_LMI_STAT_ARYSIZE   (1024/8)
+
+struct nglmistat {
+  u_char  proto[12];	/* Active proto (same as hook name) */
+  u_char  hook[12];	/* Active hook */
+  u_char  fixed;	/* If set to fixed LMI mode */
+  u_char  autod;	/* If currently auto-detecting */
+  u_char  seen[NGM_LMI_STAT_ARYSIZE];	/* bitmap DLCIs seen */
+  u_char  up[NGM_LMI_STAT_ARYSIZE];	/* bitmap DLCIs up */
+};
+.Ed
+.It Dv NGM_TEXT_STATUS
+This generic message returns is a human-readable version of the node status.
+.El
+.Sh SHUTDOWN
+This node shuts down upon receipt of a
+.Dv NGM_SHUTDOWN
+control message, or when all hooks have been disconnected.
+.Sh SEE ALSO
+.Xr netgraph 4 ,
+.Xr ng_frame_relay 8 ,
+.Xr ngctl 8 .
+.Rs
+.%T "ANSI T1.617-1991 Annex D"
+.Re
+.Rs
+.%T "ITU-T Q.933 Digital Subscriber Signalling System No. 1 - Signalling Specification for Frame Mode Basic Call Control, Annex A"
+.Re
+.Sh AUTHOR
+Julian Elisher <julian@whistle.com>
diff --git a/share/man/man4/ng_rfc1490.4 b/share/man/man4/ng_rfc1490.4
new file mode 100644
index 0000000..c7fa859
--- /dev/null
+++ b/share/man/man4/ng_rfc1490.4
@@ -0,0 +1,109 @@
+.\" Copyright (c) 1996-1999 Whistle Communications, Inc.
+.\" All rights reserved.
+.\" 
+.\" Subject to the following obligations and disclaimer of warranty, use and
+.\" redistribution of this software, in source or object code forms, with or
+.\" without modifications are expressly permitted by Whistle Communications;
+.\" provided, however, that:
+.\" 1. Any and all reproductions of the source or object code must include the
+.\"    copyright notice above and the following disclaimer of warranties; and
+.\" 2. No rights are granted, in any manner or form, to use Whistle
+.\"    Communications, Inc. trademarks, including the mark "WHISTLE
+.\"    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
+.\"    such appears in the above copyright notice or in the software.
+.\" 
+.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
+.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
+.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
+.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
+.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
+.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
+.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
+.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
+.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
+.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
+.\" OF SUCH DAMAGE.
+.\" 
+.\" Author: Archie Cobbs <archie@whistle.com>
+.\"
+.\" $FreeBSD$
+.\" $Whistle: ng_rfc1490.8,v 1.4 1999/01/25 23:46:27 archie Exp $
+.\"
+.Dd January 19, 1999
+.Dt NG_RFC1490 8
+.Os FreeBSD 3
+.Sh NAME
+.Nm ng_rfc1490
+.Nd RFC 1490 netgraph node type
+.Sh SYNOPSIS
+.Fd #include <netgraph/ng_rfc1490.h>
+.Sh DESCRIPTION
+The
+.Nm rfc1490
+node type performs protocol encapsulation, de-encapsulation, and
+multiplexing according to RFC 1490 (which has since been updated by RFC 2427).
+This particular type of encapsulation is often used on top of frame relay
+DLCI channels.
+.Pp
+The
+.Dv downstream
+hook is used to transmit and receive encapsulated frames. On the other
+side of the node, the
+.Dv inet
+and
+.Dv ppp
+hooks are used to transmit and receive raw IP frames and PPP frames,
+respectively. PPP frames are transmitted and received according to
+RFC 1973; in particular, frames appearing on the
+.Dv ppp
+hook begin with the PPP protocol number.
+.Pp
+Typically the
+.Dv inet
+hook is connected to the
+.Dv inet
+hook of an
+.Xr ng_iface 8
+node.
+.Sh HOOKS
+This node type supports the following hooks:
+.Pp
+.Bl -tag -width foobarbazum
+.It Dv downstream
+Connects to the RFC 1490 peer entity.
+.It Dv inet
+Transmits and receives raw IP frames.
+.It Dv ppp
+Transmits and receives PPP frames.
+.El
+.Sh CONTROL MESSAGES
+This node type only supports the generic control messages.
+.Sh SHUTDOWN
+This node shuts down upon receipt of a
+.Dv NGM_SHUTDOWN
+control message, or when all hooks have been disconnected.
+.Sh BUGS
+Not all of RFC 1490 is implemented.
+.Sh SEE ALSO
+.Xr netgraph 4 ,
+.Xr ng_frame_relay 8 ,
+.Xr ng_iface 8 ,
+.Xr ngctl 8 .
+.Rs
+.%A C. Brown, A. Malis
+.%T "Multiprotocol Interconnect over Frame Relay"
+.%O RFC 2427
+.Re
+.Rs
+.%A W. Simpson
+.%T "PPP in Frame Relay"
+.%O RFC 1973
+.Re
+.Sh AUTHOR
+Julian Elisher <julian@whistle.com>
diff --git a/share/man/man4/ng_socket.4 b/share/man/man4/ng_socket.4
new file mode 100644
index 0000000..31302a5
--- /dev/null
+++ b/share/man/man4/ng_socket.4
@@ -0,0 +1,127 @@
+.\" Copyright (c) 1996-1999 Whistle Communications, Inc.
+.\" All rights reserved.
+.\" 
+.\" Subject to the following obligations and disclaimer of warranty, use and
+.\" redistribution of this software, in source or object code forms, with or
+.\" without modifications are expressly permitted by Whistle Communications;
+.\" provided, however, that:
+.\" 1. Any and all reproductions of the source or object code must include the
+.\"    copyright notice above and the following disclaimer of warranties; and
+.\" 2. No rights are granted, in any manner or form, to use Whistle
+.\"    Communications, Inc. trademarks, including the mark "WHISTLE
+.\"    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
+.\"    such appears in the above copyright notice or in the software.
+.\" 
+.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
+.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
+.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
+.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
+.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
+.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
+.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
+.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
+.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
+.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
+.\" OF SUCH DAMAGE.
+.\" 
+.\" Author: Archie Cobbs <archie@whistle.com>
+.\"
+.\" $FreeBSD$
+.\" $Whistle: ng_socket.8,v 1.5 1999/01/25 23:46:27 archie Exp $
+.\"
+.Dd January 19, 1999
+.Dt NG_SOCKET 8
+.Os FreeBSD 3
+.Sh NAME
+.Nm ng_socket
+.Nd netgraph socket node type
+.Sh SYNOPSIS
+.Fd #include <netgraph/ng_message.h>
+.Fd #include <netgraph/ng_socket.h>
+.Sh DESCRIPTION
+A
+.Nm socket
+node is both a BSD socket and a netgraph node. The
+.Nm socket
+node type allows user-mode processes to participate in the kernel
+.Xr netgraph 4
+networking subsystem using the BSD socket interface.
+.Pp
+A new
+.Nm socket
+node is created by creating a new socket of type
+.Dv NG_CONTROL
+in the protocol family
+.Dv PF_NETGRAPH ,
+using the
+.Xr socket 2
+system call.
+Any control messages received by the node are received using
+.Xr recvfrom 2 ;
+the socket address argument is a
+.Dv "struct sockaddr_ng"
+containing the sender's netgraph address. Conversely, control messages
+can be sent to any node by calling
+.Xr sendto 2 ,
+supplying the recipient's address in a
+.Dv "struct sockaddr_ng" .
+The
+.Xr bind 2
+system call may be used to assign a global netgraph name to the node.
+.Pp
+To transmit and receive netgraph data packets, a
+.Dv NG_DATA
+socket must also be created using
+.Xr socket 2
+and associated with a
+.Nm socket
+node.
+.Dv NG_DATA sockets do not automatically
+have nodes associated with them; they are bound to a specific node via the
+.Xr connect 2
+system call. The address argument is the netgraph address of the
+.Nm socket
+node already created. Once a data socket is associated with a node,
+any data packets received by the node are read using
+.Xr recvfrom 2
+and any packets to be sent out from the node are written using
+.Xr sendto 2 .
+In the case of data sockets, the
+.Dv "struct sockaddr_ng"
+contains the name of the
+.Em hook
+on which the data was received or should be sent.
+.Pp
+There is a user library that simplifies using netgraph sockets; see
+.Xr netgraph 3 .
+.Sh HOOKS
+This node type supports hooks with arbitrary names (as long as
+they are unique) and always accepts hook connection requests.
+.Sh CONTROL MESSAGES
+This node type supports only the generic control messages.
+.Sh SHUTDOWN
+This node type shuts down and disappears when both the associated
+.Dv NG_CONTROL
+and
+.Dv NG_DATA
+sockets have been closed, or a
+.Dv NGM_SHUTDOWN
+control message is received. In the latter case, attempts to write
+to the still-open sockets will return
+.Er ENOTCONN .
+.Sh BUGS
+It is not possible to reject the connection of a hook, though any
+data received on that hook can certainly be ignored.
+.Sh SEE ALSO
+.Xr socket 2 ,
+.Xr netgraph 3 ,
+.Xr netgraph 4 ,
+.Xr ngctl 8 .
+.Sh AUTHOR
+Julian Elisher <julian@whistle.com>
diff --git a/share/man/man4/ng_tee.4 b/share/man/man4/ng_tee.4
new file mode 100644
index 0000000..cfcb02f
--- /dev/null
+++ b/share/man/man4/ng_tee.4
@@ -0,0 +1,110 @@
+.\" Copyright (c) 1996-1999 Whistle Communications, Inc.
+.\" All rights reserved.
+.\" 
+.\" Subject to the following obligations and disclaimer of warranty, use and
+.\" redistribution of this software, in source or object code forms, with or
+.\" without modifications are expressly permitted by Whistle Communications;
+.\" provided, however, that:
+.\" 1. Any and all reproductions of the source or object code must include the
+.\"    copyright notice above and the following disclaimer of warranties; and
+.\" 2. No rights are granted, in any manner or form, to use Whistle
+.\"    Communications, Inc. trademarks, including the mark "WHISTLE
+.\"    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
+.\"    such appears in the above copyright notice or in the software.
+.\" 
+.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
+.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
+.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
+.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
+.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
+.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
+.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
+.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
+.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
+.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
+.\" OF SUCH DAMAGE.
+.\" 
+.\" Author: Archie Cobbs <archie@whistle.com>
+.\"
+.\" $FreeBSD$
+.\" $Whistle: ng_tee.8,v 1.4 1999/01/25 23:46:27 archie Exp $
+.\"
+.Dd January 19, 1999
+.Dt NG_TEE 8
+.Os FreeBSD 3
+.Sh NAME
+.Nm ng_tee
+.Nd netgraph ``tee'' node type
+.Sh SYNOPSIS
+.Fd #include <netgraph/ng_tee.h>
+.Sh DESCRIPTION
+The
+.Nm tee
+node type has a purpose similar to the
+.Xr tee 1
+command.
+.Nm Tee
+nodes are useful for debugging or ``snooping'' on a connection
+between two netgraph nodes.
+.Nm Tee
+nodes have four hooks,
+.Dv right ,
+.Dv left ,
+.Dv right2left ,
+and
+.Dv left2right .
+All data received on
+.Dv right
+is sent unmodified to
+.Em both
+hooks
+.Dv left
+and
+.Dv right2left .
+Similarly, all data received on
+.Dv left
+is sent unmodified to both
+.Dv right
+and
+.Dv left2right .
+.Pp
+Packets may also be received on
+.Dv right2left
+and
+.Dv left2right ;
+if so, they are forwarded unchanged out hooks
+.Dv left
+and
+.Dv right ,
+respectively.
+.Sh HOOKS
+This node type supports the following hooks:
+.Pp
+.Bl -tag -width foobarbarfoo
+.It Dv right
+The connection to the node on the right.
+.It Dv left
+The connection to the node on the left.
+.It Dv right2left
+Tap for right to left traffic.
+.It Dv left2right
+Tap for left to right traffic.
+.El
+.Sh CONTROL MESSAGES
+This node type supports only the generic control messages.
+.Sh SHUTDOWN
+This node shuts down upon receipt of a
+.Dv NGM_SHUTDOWN
+control message, or when all hooks have been disconnected.
+.Sh SEE ALSO
+.Xr tee 1 ,
+.Xr netgraph 4 ,
+.Xr ngctl 8 .
+.Sh AUTHOR
+Julian Elisher <julian@whistle.com>
diff --git a/share/man/man4/ng_tty.4 b/share/man/man4/ng_tty.4
new file mode 100644
index 0000000..660b46c
--- /dev/null
+++ b/share/man/man4/ng_tty.4
@@ -0,0 +1,141 @@
+.\" Copyright (c) 1996-1999 Whistle Communications, Inc.
+.\" All rights reserved.
+.\" 
+.\" Subject to the following obligations and disclaimer of warranty, use and
+.\" redistribution of this software, in source or object code forms, with or
+.\" without modifications are expressly permitted by Whistle Communications;
+.\" provided, however, that:
+.\" 1. Any and all reproductions of the source or object code must include the
+.\"    copyright notice above and the following disclaimer of warranties; and
+.\" 2. No rights are granted, in any manner or form, to use Whistle
+.\"    Communications, Inc. trademarks, including the mark "WHISTLE
+.\"    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
+.\"    such appears in the above copyright notice or in the software.
+.\" 
+.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
+.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
+.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
+.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
+.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
+.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
+.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
+.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
+.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
+.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
+.\" OF SUCH DAMAGE.
+.\" 
+.\" Author: Archie Cobbs <archie@whistle.com>
+.\"
+.\" $FreeBSD$
+.\" $Whistle: ng_tty.8,v 1.5 1999/01/25 23:46:28 archie Exp $
+.\"
+.Dd January 19, 1999
+.Dt NG_TTY 8
+.Os FreeBSD 3
+.Sh NAME
+.Nm ng_tty
+.Nd netgraph node type that is also a line discipline
+.Sh SYNOPSIS
+.Fd #include <netgraph/ng_message.h>
+.Fd #include <netgraph/ng_tty.h>
+.Sh DESCRIPTION
+The
+.Nm tty
+node type is both a netgraph node type and a line discipline.
+A new node is created when the corresponding line discipline is
+registered on a tty device (see
+.Xr tty 4 ")."
+.Pp
+The node has a single hook called
+.Dv hook .
+Incoming bytes received on the tty device are sent out on this hook,
+and frames received on
+.Dv hook
+are transmitted out on the tty device.
+No modification to the data is performed in either direction.
+While the line discipline is installed on a tty, the normal
+read and write operations are unavailable, returning
+.Er EIO .
+.Pp
+The node supports an optional ``hot character.'' If set to non-zero, incoming
+data from the tty device is queued until this character is seen.
+This avoids sending lots of mbufs containing a small number of bytes,
+but introduces potentially infinite latency.
+The default hot character is 0x7e, consistent with
+.Dv hook
+being connected to a
+.Xr ng_async 8
+type node. The hot character has no effect on the transmission of data.
+.Pp
+The node will attempt to give itself the same netgraph name as the name
+of the tty device.
+In any case, information about the node is available via the netgraph
+.Xr ioctl 2
+command
+.Dv NGIOCGINFO .
+This command returns a
+.Dv "struct nodeinfo"
+similar to the
+.Dv NGM_NODEINFO
+netgraph control message.
+.Sh HOOKS
+This node type supports the following hooks:
+.Pp
+.Bl -tag -width foobar
+.It Dv hook
+.Xr tty 4
+serial data contained in
+.Dv mbuf
+structures, with arbitrary inter-frame boundaries.
+.El
+.Sh CONTROL MESSAGES
+This node type supports the generic control messages, plus the following:
+.Bl -tag -width foo
+.It Dv NGM_TTY_SET_HOTCHAR
+This command takes an integer argument and sets the hot character
+from the lower 8 bits. A hot character of zero disables queueing,
+so that all received data is forwarded immediately.
+.It Dv NGM_TTY_GET_HOTCHAR
+Returns an integer containing the current hot character in the lower
+eight bits.
+.Sh SHUTDOWN
+This node shuts down when the corresponding device is closed
+(or the line discipline is uninstalled on the device).
+The
+.Dv NGM_SHUTDOWN
+control message is not valid, and always returns the error
+.Er EOPNOTSUPP .
+.Sh BUGS
+The
+.Nm tty
+type registers its line discipline when the type is installed,
+where it is dynamically assigned an integer index.
+Unfortunately, there's no way to know what this integer is
+except by reading the output of
+.Xr dmesg 8 .
+The fix for this is to have line disciplines identified by
+unique ASCII strings instead of fixed integer constants,
+or else to assign one of those constants to
+.Nm ng_tty .
+.Pp
+The serial driver code also has a notion of a ``hot character.''
+Unfortunately, this value is statically defined in terms of the
+line discipline and cannot be changed.
+Therefore, if a hot character other than 0x7e (the default) is set for the
+.Nm tty
+node, the node has no way to convey this information to the
+serial driver, and sub-optimal performance may result.
+.Sh SEE ALSO
+.Xr ioctl 2 ,
+.Xr netgraph 4 ,
+.Xr tty 4 ,
+.Xr ng_async 8 ,
+.Xr ngctl 8 .
+.Sh AUTHOR
+Archie Cobbs <archie@whistle.com>
diff --git a/share/man/man4/ng_vjc.4 b/share/man/man4/ng_vjc.4
new file mode 100644
index 0000000..bc0a8b1
--- /dev/null
+++ b/share/man/man4/ng_vjc.4
@@ -0,0 +1,188 @@
+.\" Copyright (c) 1996-1999 Whistle Communications, Inc.
+.\" All rights reserved.
+.\" 
+.\" Subject to the following obligations and disclaimer of warranty, use and
+.\" redistribution of this software, in source or object code forms, with or
+.\" without modifications are expressly permitted by Whistle Communications;
+.\" provided, however, that:
+.\" 1. Any and all reproductions of the source or object code must include the
+.\"    copyright notice above and the following disclaimer of warranties; and
+.\" 2. No rights are granted, in any manner or form, to use Whistle
+.\"    Communications, Inc. trademarks, including the mark "WHISTLE
+.\"    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
+.\"    such appears in the above copyright notice or in the software.
+.\" 
+.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
+.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
+.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
+.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
+.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
+.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
+.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
+.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
+.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
+.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
+.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
+.\" OF SUCH DAMAGE.
+.\" 
+.\" Author: Archie Cobbs <archie@whistle.com>
+.\"
+.\" $FreeBSD$
+.\" $Whistle: ng_vjc.8,v 1.4 1999/01/25 23:46:28 archie Exp $
+.\"
+.Dd January 19, 1999
+.Dt NG_VJC 8
+.Os FreeBSD 3
+.Sh NAME
+.Nm ng_vjc
+.Nd Van Jacobsen compression netgraph node type
+.Sh SYNOPSIS
+.Fd #include <net/slcompress.h>
+.Fd #include <netgraph/ng_vjc.h>
+.Sh DESCRIPTION
+The
+.Nm vjc
+node type performs Van Jacobsen compresion, which is used
+over PPP, SLIP, and other point-to-point IP connections to
+compress TCP packet headers.  The
+.Dv ip
+hook represents the uncompressed side of the node, while the
+.Dv vjcomp ,
+.Dv vjuncomp ,
+and
+.Dv vjip
+nodes represent the compressed side of the node. Packets received on the
+.Dv ip
+will be compressed or passed through as appropriate. Packets received
+on the other three hooks will be uncompressed as appropriate.
+.Pp
+Van Jacobsen compression only applies to TCP packets.
+Only ``normal'' (i.e., common case) TCP packets are actually compressed.
+These are output on the
+.Dv vjcomp
+hook. Other TCP packets are run through the state machine but not
+compressed; these appear on the
+.Dv vjuncomp
+hook.
+Other non-TCP IP packets are forwarded unchanged to
+.Dv vjip .
+.Pp
+When connecting to a
+.Xr ng_ppp 8
+node, the
+.Dv vjuncomp ,
+.Dv vjcomp , 
+and
+.Dv vjip
+nodes should be connected to the
+.Xr ng_ppp 8
+node's
+.Dv vjcomp ,
+.Dv vjuncomp ,
+and
+.Dv ip
+nodes, respectively.
+.Sh HOOKS
+This node type supports the following hooks:
+.Pp
+.Bl -tag -width foobarbazi
+.It Dv ip
+Upstream (uncompressed) IP packets.
+.It Dv vjcomp
+Downstream compressed TCP packets.
+.It Dv vjuncomp
+Downstream uncompressed TCP packets.
+.It Dv vjip
+Downstream uncompressed IP packets.
+.Sh CONTROL MESSAGES
+This node type supports the generic control messages, plus the following:
+.Bl -tag -width foo
+.It Dv NGM_VJC_CONFIG
+This command resets the compression state and configures it according
+to the supplied
+.Dv "struct ngm_vjc_config"
+argument. This structure contains the following fields:
+.Bd -literal -offset 4n
+struct ngm_vjc_config {
+  u_char   enabled;       /* Enable compression/decompression */
+  u_char   numChannels;   /* Number of outgoing channels */
+  u_char   compressCID;   /* OK to compress outgoing CID's */
+};
+.Ed
+.Pp
+When
+.Dv enabled
+is set to zero, the node operates in ``pass through'' mode, only
+accepting packets on the
+.Dv ip
+and
+.Dv vjip
+hooks.
+.Dv numChannels
+should be set to the number of compression channels, and is a value
+between 3 and 16, inclusive.
+.Pp
+The
+.Dv compressCID
+field indicates whether it is OK to compress the CID field for
+outgoing compressed TCP packets. This value should be zero unless
+either (a) it not possible for an incoming frame to be lost, or
+(b) lost frames can be reliably detected and a
+.Dv NGM_VJC_RECV_ERROR
+mesages is immediately sent whenever this occurs.
+.It Dv NGM_VJC_GET_STATE
+This command returns the node's current state described by the
+.Dv "struct slcompress"
+structure, which is defined in
+.Dv "net/slcompress.h" .
+.It Dv NGM_VJC_CLR_STATS
+Clears the node statistics counters. Statistics are also cleared whenever the
+.Dv enabled
+field is changed from zero to one by a
+.Dv NGM_VJC_CONFIG
+control message.
+.It Dv NGM_VJC_RECV_ERROR
+When the
+.Dv compressCID
+is set to one, this message must be sent to the node immediately
+after detecting that a recieved frame has been lost, due to a bad
+checksum or for any other reason. Failing to do this can result
+in corrupted TCP stream data.
+.Sh SHUTDOWN
+This node shuts down upon receipt of a
+.Dv NGM_SHUTDOWN
+control message, or when all hooks have been disconnected.
+.Sh BUGS
+This node type requires that the file
+.Dv "net/slcompress.c"
+was compiled into the kernel. Currently the only way to insure this
+is to include the
+.Dv slip ,
+.Dv ppp ,
+or
+.Dv i4bipr
+pseudo-devices in your kernel compilation. In the future there should
+be a kernel option that causes inclusion of this file without requiring
+one of these drivers.
+.Sh SEE ALSO
+.Xr netgraph 4 ,
+.Xr ng_ppp 8 ,
+.Xr ng_iface 8 ,
+.Xr ngctl 8 .
+.Rs
+.%A V. Jacobsen
+.%T "Compressing TCP/IP Headers"
+.%O RFC 1144
+.Re
+.Rs
+.%A G. McGregor
+.%T "The PPP Internet Control Protocol (IPCP)"
+.%O RFC 1332
+.Re
+.Sh AUTHOR
+Archie Cobbs <archie@whistle.com>