Huawei Aolynk DR811 IP Addresses, Network Masks, and Subnets, Structure of an IP Address

User Manual
Aolynk DR811/DR814 ADSL2+Broadband Router	6 IP Addresses, Network Masks, and Subnets

6 IP Addresses, Network Masks, and Subnets

6.1 IP Addresses

&Note:

This section refers only to IP addresses for IPv4 (version 4 of the Internet Protocol). IPv6 addresses are not covered.

This section assumes basic knowledge of binary numbers, bits, and bytes.

IP addresses, the Internet version of telephone numbers, are used to identify individual nodes (computers or devices) on the Internet. Every IP address contains four numbers, each from 0 to 255 and separated by dots (periods), e.g. 20.56.0.211. These numbers are called, from left to right, field1, field2, field3, and field4.

This style of writing IP addresses as decimal numbers separated by dots is called dotted decimal notation. The IP address 20.56.0.211 is read "twenty dot fifty-six dot zero dot two-eleven."

6.1.1 Structure of an IP Address

IP addresses have a hierarchical design similar to that of telephone numbers. For example, a 7-digit telephone number starts with a 3-digit prefix that identifies a group of thousands of telephone lines, and ends with four digits that identify one specific line in that group.

Similarly, IP addresses contain two kinds of information.

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Network ID: Identifies a particular network within the Internet or intranet

Host ID: Identifies a particular computer or device on the network

The first part of every IP address contains the network ID, and the rest of the address contains the host ID. The length of the network ID depends on the network's class (refer to the following section). Table 7-1 shows the structure of an IP address.

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