Extron electronic USP 507 manual Subnetting — A Primer, Gateways, Local and remote devices, Help

Local echo can be turned off by entering unset local_echo at the Telnet prompt. If your computer is connected to the USP 507, and you need to access the Telnet prompt to turn local echo off, enter the Escape sequence (Ctrl + ]).

Setting carriage return-line feed

Unless commanded otherwise, Telnet transmits a line feed character only (no carriage return) to the connected processor when you press the Enter key. This is the correct setting for SIS communication with the processor. The Telnet set crlf command forces Telnet to transmit carriage return and line feed characters when Enter is pressed; however, if crlf is set, the SIS link with the processor does not function properly.

Closing the link to the processor

To close the link to the processor, access the Telnet prompt by entering the Escape sequence (Ctrl + ]). 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 USP 507, access the Telnet prompt by entering the Escape sequence (Ctrl + ]).

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 USP 507 and the mail server gateway. To understand subnetting at the level required to install and operate the USP 507, you must understand the concepts of a gateway, local and remote devices, IP addresses and octets, and subnet masks and octets.

Gateways

The USP 507 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 via 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 manual, subnetting is an issue when you are using the controlling PC to set TCP/IP values in the USP 507.

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) (figure B-4). 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.

Typical IP Address: 192.168.254.254

Octets

Figure B–4 — IP address and octets

USP 507 • Ethernet Connection B-5