Cip Addresses, Network Masks & Subnets; Ip Addresses - Mitel 1000 Owner's Manual

IP Addresses, Network Masks & Subnets
C
Note

IP Addresses

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's version of telephone numbers, are used
to identify individual nodes (computers or systems) 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."
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:
•
Network ID
Identifies a particular network within the Internet or intranet
•
Host ID
Identifies a particular computer or system 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 (see following section). The table
below shows the structure of an IP address.
Field1
Class A Network ID
Class B Network ID
Class C
Here are some examples of valid IP addresses:
Class A: 10.30.6.125 (network = 10, host = 30.6.125)
Class B: 129.88.16.49 (network = 129.88, host = 16.49)
Class C: 192.60.201.11 (network = 192.60.201, host = 11)
Network classes
The three commonly used network classes are A, B, and C. (There
is also a class D but it has a special use beyond the scope of this
discussion.) These classes have different uses and characteristics.
Class A networks are the Internet's largest networks, each with
room for over 16 million hosts. Up to 126 of these huge networks
can exist, for a total of over 2 billion hosts. Because of their huge
size, these networks are used for WANs and by organizations at the
infrastructure level of the Internet, such as your ISP.
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Field2 Field3
Host ID
Host ID
Network ID
Field4
Host ID