CHAPTER 5
Physical addressing:-A physical address is the hardware-level address used by the Ethernet
interface to communicate on the network. Every device must have a unique physical address.
This is often referred to as its MAC (Media Access Control) address. An Ethernet physical
address is six bytes long and consists of six hexadecimal numbers, usually separated by colon
characters (:).
Logical addresses:-A logical address is a network-layer address that is interpreted by a
protocol handler. Logical addresses are used by networking software to allow packets to be
independent of the physical connection of the network, that is, to work with different network
topologies and types of media. Each type of protocol has a different kind of logical address
an IP address (IPv4) consists of four decimal numbers separated by period (.) characters, for
example:
130.57.64.1
172.18.0.1etc.
Internet Version protocol 4 (IPV4):-
1. The IPv4 address is a 32-bit number that uniquely identifies a network interface on a
machine. An IPv4 address is typically written in decimal digits, formatted as four 8-bit
fields that are separated by periods. Each 8-bit field represents a byte of the IPv4
address. This form of representing the bytes of an IPv4 address is often referred to as
the dotted-decimal format.
2. The bytes of the IPv4 address are further classified into two parts: the network part and
the host part. The following figure shows the component parts of a typical IPv4 address,
129.144.50.56.
, Classful Addressing
An IP address is 32-bit
bit long. An IP address is divided into sub
sub-classes:
o Class A
o Class B
o Class C
o Class D
o Class E
An ip address is divided into two parts:
o Network ID: It represents the number of networks.
o Host ID: It represents the number of hosts .
Class A:-
In Class A, an IP address is assigned to those networks that contain a large number of hosts.
o The network ID is 8 bits long.
o The host ID is 24 bits long.
Physical addressing:-A physical address is the hardware-level address used by the Ethernet
interface to communicate on the network. Every device must have a unique physical address.
This is often referred to as its MAC (Media Access Control) address. An Ethernet physical
address is six bytes long and consists of six hexadecimal numbers, usually separated by colon
characters (:).
Logical addresses:-A logical address is a network-layer address that is interpreted by a
protocol handler. Logical addresses are used by networking software to allow packets to be
independent of the physical connection of the network, that is, to work with different network
topologies and types of media. Each type of protocol has a different kind of logical address
an IP address (IPv4) consists of four decimal numbers separated by period (.) characters, for
example:
130.57.64.1
172.18.0.1etc.
Internet Version protocol 4 (IPV4):-
1. The IPv4 address is a 32-bit number that uniquely identifies a network interface on a
machine. An IPv4 address is typically written in decimal digits, formatted as four 8-bit
fields that are separated by periods. Each 8-bit field represents a byte of the IPv4
address. This form of representing the bytes of an IPv4 address is often referred to as
the dotted-decimal format.
2. The bytes of the IPv4 address are further classified into two parts: the network part and
the host part. The following figure shows the component parts of a typical IPv4 address,
129.144.50.56.
, Classful Addressing
An IP address is 32-bit
bit long. An IP address is divided into sub
sub-classes:
o Class A
o Class B
o Class C
o Class D
o Class E
An ip address is divided into two parts:
o Network ID: It represents the number of networks.
o Host ID: It represents the number of hosts .
Class A:-
In Class A, an IP address is assigned to those networks that contain a large number of hosts.
o The network ID is 8 bits long.
o The host ID is 24 bits long.
