Extron electronic 7200, 3200 manual Subnetting a Primer, Gateways, Local and Remote Devices

Quit

Exit the Telnet utility by typing quit and then pressing <Enter> at the Telnet prompt. If you are connected to the FOX matrix switcher, access the Telnet prompt by typing the Escape character (<Ctrl>+<]>).

Subnetting — A Primer

It is not the purpose of this guide to describe TCP/IP protocol in detail. However, some understanding of TCP/IP subnetting (a subnet is a subset of a network — a set of IP devices that have portions of their IP addresses in common) is necessary in order to understand the interaction of the FOX matrix switcher and the mail server gateway. To understand subnetting at the level required to install and operate the FOX matrix switcher, you must understand the concepts of a gateway, local and remote devices, IP addresses and octets, and subnet masks and octets.

Gateways

The FOX matrix switcher can communicate with the e-mail server that the switcher 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 guide, subnetting is an issue when you are using the controlling PC to set TCP/IP and e-mail values in the matrix switcher (see IP Settings/Options Window on page 76 and Email Settings Page on page 101). When you are setting up the variables for e-mail notification, which may include subnetting, the matrix switcher 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,” separated by dots (periods) (see figure 74). Each octet can be numbered from 000 through 255. Leading zeroes, up to three digits total per octet, are optional. Values of 256 and above are invalid.

Typical IP Address: 192.168.254.254

Octets

Figure 74. Typical IP Address

Subnet Masks and Octets

The subnet mask (see figure 75) is used to determine whether the local and remote devices are on the same subnet or different subnets. The subnet mask consists of four numeric octets separated by dots. Each octet can be numbered from 000 through 255. Leading zeroes, up to three digits total per octet, are optional. Each octet typically contains either 255 or 0. The octets determine whether or not the same octets of two IP addresses will be compared when determining if two devices are on the same subnet.

255 indicates that this octet will be compared between two IP addresses.

0 indicates that this octet will not be compared between two IP addresses.

Typical Subnet Mask: 255.255.0.0

Octets

Figure 75. Typical Subnet Mask

FOX Matrix 3200 and 7200 Switchers • Ethernet Connection 122