More About; Ip Addresses And Subnet Masks - Cisco ROUTER-SDM-CD User Manual

IP Addresses and Subnet Masks

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These topics provide more information about subjects that Cisco SDM online help
discusses.
This topic provides background information about IP addresses and subnet masks,
and shows you how to use this information when entering addresses and masks in
Cisco SDM.
IP version 4 addresses are 32 bits, or 4 bytes, in length. This address "space" is
used to designate the following:
Network number
•
Optional subnetwork number
•
A host number
•
Cisco SDM does not support IP version 6.
Cisco SDM requires you to enter IP addresses in dotted-decimal format. This
format makes addresses easier for people to read and manipulate, by grouping the
32 bits into 4 octets which are displayed in decimal, separated by periods or
"dots," for example, 172.16.122.204. The decimal address 172.16.122.204
represents the binary IP address shown in the following figure.
Cisco Router and Security Device Manager 2.5 User's Guide
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