User`s guide

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Allow up to n connections
The value in this text box specifies the number of sockets listening for new SSH connections
(default 1).
Host Key 1 Filename
The value in this text box is the filename of either an SSH V1 or V2 host key. It is highly
recommended that the filename be prefixed with “priv” to ensure that the key cannot be
easily accessed and compromised. This key may be generated using the facilities described
in the Certificates section of this manual.
Host Key 2 Filename
The value in this text box is the filename of either an SSH V1 or V2 key as above.
Note:
The maximum length for these filenames is 12 characters and they must use the DOS 8.3
file naming convention.
Maximum login time s seconds
The value in this text box specifies the maximum length of time (in seconds) that a user is
allowed to successfully complete the login procedure once the SSH socket has been opened.
The socket is closed if the user has not completed a successful login within this period.
Maximum login attempts n
The value in this text box specifies the maximum number of login attempts allowed in any
one session before the SSH socket will be closed.
Use Deflate compression No/Yes, level n
The radio buttons select whether or not DEFLATE compression will be used. If compression
is selected, the compression level is chosen from the drop-down list.
Enable Port Forwarding
When checked, this checkbox enables the router to accept traffic on ports other than 23.
This functionality is for use with SSH client applications (such as PuTTY) that has port
forwarding capability. For example, one the SSH connection is active, traffic for the HTTP
port 80 can be sent to the router securely.
Command Session IP Address a.b.c.d Port p
The values in these two text boxes are used to specify the host IP address and port number
that the router will use to handle incoming requests for a command session from SSH
clients. This is instead of the router’s normal command interpreter. For example, if the
values are IP address 127.0.0.1, port 4000, the SSH client will make a direct connection to
ASY 0 and the device attached to ASY 0 will receive and process the commands from the
SSH client.
Enable support for SSH v1.5
When checked, this checkbox allows the server to negotiate SSH V1.5. The router must also
have a SSH V1 key present and the filename entered into the SSG configuration.
Server key size
This option applies to V1 SSH. During initialisation of an SSH session, the server sends its
host key and a server key (which should be of a different size to the host key). The router
generates this key automatically but the length of the server key is determined by this
parameter. If when this value is set it is too similar to the length of the host key, the router
will automatically adjust the selected value so that the key sizes are significantly different.