Page 17 - DCAP202_Fundamentals of Web Programming

Fundamentals of Web Programming

Notes 1.6.3 IP Address Classes and their Formats

IP addresses are 32 bit integers which are represented in the familiar dot based notation. The dot
based notation is nothing but a decimal representation for each byte of the IP address.

Example: An IP address with a hex value of 0x800A080B is represented as 128.10.8.11.
The internet, as the name suggests, is a network of networks. Thus to uniquely identify a host on
the internet, one needs to know the network’s id and the host’s id in the network. Thus IP address
consist of two components, the network id and the host id.

Did u know? The network id is the number assigned to a network in the internet. Host id
represents the id assigned to a host in the network.
Figure 1.4 shows different classes of IP addresses. These addresses differ in the number of bits
assigned to the network and host ids. Different classes of addresses serve different needs.

Example: A class A IP address is suitable when the internet consists of a small number of
networks but each network consists of a large number of hosts. On the other extreme, class C
addressing is suitable for internets with a very large number of networks, with a small number
of hosts per network.
Figure 1.4: Different Classes of IP Addresses

1.6.4 Relation of IP Address to Physical Address

Network device has two types of addresses, one called the logical address — in most cases this
is the IP address — and the other one being the physical address — also known as the MAC
address.

The IP address is an address bound to the network device, i.e., computer, via software. In a
Windows-powered computer, the Windows operating system allows the user to configure the
IP address the specific workstation will have. This IP address is used to allow all network aware

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