Extron Electronics SMX System User Guide - Manual (Page 117)

SMX System MultiMatrix Switcher • Ethernet Control 111
Setting carriage return line feed
Unless commanded otherwise, Telnet transmits a line feed character only (no carriage
return) to the connected switcher when the key is pressed. This is the correct
setting for SIS communication with the SMX. The Telnet
set crlf command forces Telnet
to transmit carriage return and line feed characters when is pressed; however, if
crlf is set, the SIS link with the switcher does not function properly.
Closing the link to the switcher
To close the link to the SMX, access the Telnet prompt by entering the escape sequence
( + <]>). At the Telnet prompt, enter
close .
Help
For Telnet command definitions, enter ? at the Telnet prompt.
Exiting Telnet (Quit command)
Exit the Telnet utility by entering quit at the Telnet prompt. If you are connected to the SMX
switcher, access the Telnet prompt by entering the escape sequence ( + <]>).
Subnetting — A Primer
A subnet is a subset of a network — a set of IP devices that have portions of their IP
addresses in common. It is not the purpose of this manual to describe TCP/IP protocol
in detail. However, some understanding of TCP/IP subnetting is necessary in order
to understand the interaction of the SMX and the mail server gateway. To understand
subnetting at the level required to install and operate the SMX, you must understand the
concepts of a gateway, local and remote devices, IP addresses and octets, and subnet
masks and octets.
Gateways
The SMX can communicate with the e-mail server that it uses for e-mail notification directly
(if they are on the same subnet), or the communication can be routed through a gateway
(a computer that provides a link between different subnets).
Local and Remote Devices
The local and remote devices are defined from the point of view of the function being
described. In this guide, subnetting is an issue when you are using the controlling PC to set
TCP/IP and e-mail values in the SMX (see
IP Settings/Options on page 77, SMX Control
Software on page 59, Email Settings Page on page 94, and HTML Configuration
and Control on page 87). When setting up the variables for e-mail notification, which may
include subnetting, the SMX is the local device and the e-mail server is the remote device.
IP Addresses and Octets
Valid IP addresses consist of four 1-, 2-, or 3-digit numeric subfields, properly called octets,
which are separated by dots (periods) (see figure 68). Each octet can be numbered from
000 through 255. Leading zeros, up to 3 digits total per octet, are optional. Values of 256
and above are invalid.
192.168.254.254 Typical IP Address:
Octets
Figure 68. IP Address and Octets