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Diffstat (limited to 'crypto/openssh/README.hpn')
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diff --git a/crypto/openssh/README.hpn b/crypto/openssh/README.hpn deleted file mode 100644 index 674827f..0000000 --- a/crypto/openssh/README.hpn +++ /dev/null @@ -1,120 +0,0 @@ -Notes: - -NONE CIPHER: - To use the NONE option you must have the NoneEnabled switch set on the server - and you MUST have *both* NoneEnabled and NoneSwitch set to yes on the client. - The NONE feature works with ALL ssh subsystems (as far as we can tell) - as long as there is no tty allocated. - If a user uses the -T switch to prevent a tty being created the NONE cipher - will be disabled. - - -PERFORMANCE: - The performance increase will only be as good as the network and TCP stack - tuning on the reciever side of the connection allows. As a rule of thumb a - user will need at least 10Mb/s connection with a 100ms RTT to see a doubling - of performance. - The HPN-SSH home page http://www.psc.edu/networking/projects/hpn-ssh - describes this in greater detail. - - -BUFFER SIZES: -- if HPN is disabled the receive buffer size will be set to the OpenSSH default - of 64K. - -- if a HPN system connects to a non-HPN system the receive buffer will - be set to the HPNBufferSize value. The default is 2MB but user adjustable. - -- If a HPN to HPN connection is established a number of different things might - happen based on the user options and conditions. - - Conditions: HPNBufferSize NOT Set, TCPRcvBufPoll enabled, TCPRcvBuf NOT Set - Result: HPN Buffer Size = up to 64MB - This is the default state. The HPN buffer size will grow to a maximum of - 64MB as the TCP receive buffer grows. The maximum HPN Buffer size of 64MB - is geared towards 10GigE transcontinental connections. - - Conditions: HPNBufferSize NOT Set, TCPRcvBufPoll disabled, TCPRcvBuf NOT Set - Result: HPN Buffer Size = TCP receive buffer value. - Users on non-autotuning systesm should disable TCPRcvBufPoll in the - ssh_cofig and sshd_config - - Conditions: HPNBufferSize SET, TCPRcvBufPoll disabled, TCPRcvBuf NOT Set - Result: HPN Buffer Size = minmum of TCP receive buffer and HPNBufferSize. - This would be the system defined TCP receive buffer (RWIN). - - Conditions: HPNBufferSize SET, TCPRcvBufPoll disabled, TCPRcvBuf SET - Result: HPN Buffer Size = minmum of TCPRcvBuf and HPNBufferSize. - Generally there is no need to set both. - - Conditions: HPNBufferSize SET, TCPRcvBufPoll enabled, TCPRcvBuf NOT Set - Result: HPN Buffer Size = grows to HPNBufferSize - The buffer will grow up to the maximum size specified here. - - Conditions: HPNBufferSize SET, TCPRcvBufPoll enabled, TCPRcvBuf SET - Result: HPN Buffer Size = minmum of TCPRcvBuf and HPNBufferSize. - Generally there is no need to set both of these, especially on autotuning - systems. However, if the users wishes to override the autotuning this would - be one way to do it. - - Conditions: HPNBufferSize NOT Set, TCPRcvBufPoll enabled, TCPRcvBuf SET - Result: HPN Buffer Size = TCPRcvBuf. - This will override autotuning and set the TCP recieve buffer to the user - defined value. - - -HPN SPECIFIC CONFIGURATION OPTIONS: - -- HPNDisabled=[yes/no] client/server - In some situations, such as transfers on a local area network, the impact - of the HPN code produces a net decrease in performance. In these cases it is - helpful to disable the HPN functionality. By default HPNDisabled is set to no. - -- HPNBufferSize=[int]KB client/server - This is the default buffer size the HPN functionality uses when interacting - with non-HPN SSH installations. Conceptually this is similar to the TcpRcvBuf - option as applied to the internal SSH flow control. This value can range from - 1KB to 64MB (1-65536). Use of oversized or undersized buffers can cause - performance problems depending on the roud trip time of the network path. - The default size of this buffer is 2MB. - -- TcpRcvBufPoll=[yes/no] client/server - Enable or disable the polling of the TCP receive buffer through the life - of the connection. You would want to make sure that this option is enabled - for systems making use of autotuning kernels (linux 2.4.24+, 2.6, MS Vista, - FreeBSD 7.x and later). Default is yes. - -- TcpRcvBuf=[int]KB client - Set the TCP socket receive buffer to n Kilobytes. It can be set up to the - maximum socket size allowed by the system. This is useful in situations where - the TCP receive window is set low but the maximum buffer size is set higher - (as is typical). This works on a per TCP connection basis. You can also use - this to artifically limit the transfer rate of the connection. In these cases - the throughput will be no more than n/RTT. The minimum buffer size is 1KB. - Default is the current system wide TCP receive buffer size. - -- NoneEnabled=[yes/no] client/server - Enable or disable the use of the None cipher. Care must always be used when - enabling this as it will allow users to send data in the clear. However, it - is important to note that authentication information remains encrypted even - if this option is enabled. Set to no by default. - -- NoneSwitch=[yes/no] client - Switch the encryption cipher being used to the None cipher after - authentication takes place. NoneEnabled must be enabled on both the client - and server side of the connection. When the connection switches to the NONE - cipher a warning is sent to STDERR. The connection attempt will fail with an - error if a client requests a NoneSwitch from the server that does not - explicitly have NoneEnabled set to yes. - Note: The NONE cipher cannot be used in interactive (shell) sessions and it - will fail silently. Set to no by default. - - -CREDITS: - - This patch was conceived, designed, and led by Chris Rapier (rapier@psc.edu) - The majority of the actual coding for versions up to HPN12v1 was performed - by Michael Stevens (mstevens@andrew.cmu.edu). - The MT-AES-CTR cipher was implemented by Ben Bennet (ben@psc.edu). - This work was financed, in part, by Cisco System, Inc., the National Library - of Medicine, and the National Science Foundation. |