1104-02: System Subnet Mask [System: Config: Communication: Ethernet (1104): Subnet Mask]

Use this option to set the DSX system’s subnet mask. The subnet mask distinguishes IP addresses of computers on your LAN from those outside your network (e.g., on the internet or a private WAN). Like the IP address, the subnet mask also consists of four 3-digit octets. The subnet mask uses the entry 255 to define the masked octets and 0 to define the unmasked octets.

A typical entry of 255.255.255.0 means if two IP addresses have the same first three octets, they are on the same network. For example, if:

• The IP addresses of the LAN begin with 192.168.1, and
• The subnet mask 255.255.255.0, then
• The network routers know that 192.168.1.250 and 192.168.1.1 are on the same network.

Requests to these addresses are kept within the LAN (as opposed to being routed to the internet). When the first three octets don’t match, the requests are routed out of the LAN.

Features Related to this Program

Telephone Features

• None

IntraMail Features

• None

Program Options

• Digits using 0-9, 12 max in the format xxx.xxx.xxx.xxx.
• With DHCP disabled in 1103-01: DHCP Enabled, the default is 0.0.0.0 (unassigned).