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Understanding Ascend subnet notation

An IP subnet or subnet mask is a way to subdivide a network into smaller networks, so you can have a greater number of nodes on a network with a single IP address. The subnet notation that you use with your Ascend unit is slightly different from traditional decimal notation. With Ascend units, the IP subnet is a number that you append to the IP address. For example, 195.112.56.75/14, 195.112.56.75/15, and 195.112.56.75/16 are all IP addresses with subnets of 14, 15, and 16.

What does mask mean in this context?

A mask defines a pattern for a value that you (or some other entity will) supply. In the case of subnets, there is a certain pattern that is valid when defining a subnet (that is, you cannot use any random number, since it wouldn't be meaningful or be recognized by the network). Subnets are setup by network administrators based on how many hosts and IP addresses are available in the facility, and the number of smaller networks that need to be defined. The table below shows a few valid dotted decimal masks for subnets and their associated slash mask. The table also shows you how many subnets and hosts (or nodes) can exist using these values.

Decimal Mask Slash Mask Subnets available hosts available
255.255.255.0 /24 2097152 254
255.255.255.192 /26 2 62
255.255.255.224 /27 6 30
255.255.255.240 /28 14 14
255.255.255.248 /29 30 6
255.255.255.252 /30 62 2
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