Tripp Lite B092-016 Owner's Manual page 40

Chapter 4: Serial Port, Device and User Configuration
SSH
TCP
RFC2217
It is recommended that the User or Administrator uses SSH as the protocol for connecting to serial
consoles attached to the Console Server when communicating over the Internet or any other public
network. This will provide an authenticated, encrypted connection between the SSH client program
on the remote user's computer and the Console Server. The user's communication with the serial
device attached to the Console Server is therefore secure.
It is recommended for Users and Administrators to use SDT Connector when making an SSH
connection to the consoles on devices attached to the Console Server's serial ports. Configure the
SDT Connector with the Console Server as a gateway, then as a host, and enable SSH service on
Port (3000 + serial port #) i.e. 3001-3048 (refer to Chapter 6).
You can also use common communications packages, like PuTTY or SSHTerm to SSH connect
directly to port address IP Address _ Port (3000 + serial port #) i.e. 3001–3048.
Alternately SSH connections can be configured using the standard SSH port 22. The serial port
being accessed is then identified by appending a descriptor to the username. This syntax supports
any of:
<username>:<portXX>
<username>:<port label>
<username>:<ttySX>
<username>:<serial>
So for a user named 'fred' to access serial port 2, when setting up the SSHTerm or the PuTTY SSH
client, instead of typing username = fred and ssh port = 3002, the alternate is to type username
= fred:port02 (or username = fred:ttyS1) and ssh port = 22.
Or, by typing username=fred:serial and ssh port = 22, the user is presented with a port selection
option:
This syntax enables users to set up SSH tunnels to all serial ports with only a single IP port 22
having to be opened in their firewall/gateway.
RAW TCP allows connections directly to a TCP socket. Communications programs such as PuTTY
also support RAW TCP; however, this protocol would usually be used by a custom application. For
RAW TCP , the default port address is IP Address _ Port (4000 + serial port #) i.e. 4001 – 4048.
RAW TCP also enables the serial port to be tunneled to a remote Console Server, so two serial port
devices can be transparently interconnected over a network (see Chapter 4.1.6 – Serial Bridging).
Selecting RFC2217 enables serial port redirection on that port. For RFC2217, the default port
address is IP Address _ Port (5000 + serial port #) i.e. 5001 – 5048.
You will also need to run serial port redirector software on your desktop computer. This software,
which supports RFC2217 virtual com ports, is available commercially and as freeware, for Windows
UNIX and Linux, and it allows you to use a serial device connected to the remote Console Server as
if it were connected to your local serial port.
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