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CIDR

is this routing using summarary addresses ? can anyone tell me how we use or waht would we class as cidr ?

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Re: CIDR

Carl,

CIDR refers to subnetting networks down or up that are on classful boundarys.

Primary Classful networks would include the following:

Class A 0.0.0.0-127.0.0.0

Class B 128.0.0.0-191.0.0.0

Class C 192.0.0.0-223.0.0.0

CIDR would be taking 10.0.0.0 and breaking it down so that were using only the space we need for a network. Example would be using just 254 address for a lan or 4 address's for a single line.

10.1.1.0/24 LAN 254 address's

10.1.0.0/30 WAN Link 4 address's

To summarzise these you would be able to do

10.1.0.0/23 that would includ both the networks above.

Basically CIDR is the breaking down of classful networks to use only a portion of that network. Depending on who you talk to is the process of breaking down large classful networks and sumarrising those smaller networks where needed to clean up routing tables.

Patrick

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