Subnetting — a primer, Gateways, Local and remote devices – Extron Electronics MTPX Plus Series User Guide User Manual
Page 157: Ip addresses and octets, Subnet masks and octets, In the “ether
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 MTPX Plus switcher and the mail server gateway. To understand subnetting
at the level required to install and operate the MTPX Plus switcher, you must understand the
concepts of a gateway, local and remote devices, IP addresses and octets, and subnet masks
and octets.
Gateways
The MTPX Plus 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
and
). 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
). 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.
192.168.254.254
Typical IP Address:
Octets
Figure 94.
Typical IP Address
Subnet Masks and Octets
The subnet mask (see
) 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.
255.255.0.0
Typical Subnet Mask:
Octets
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.
Figure 95.
Typical Subnet Mask
MTPX Plus Series • Ethernet Connection 151