ARP protocol means address resolution protocol. ARP protocol works by broadcasting Packets to all hosts attached to LAN. ARP contains IP address in which Sender is interested in communication with hosts keep a list of ARP responses in and ARP table.

ARP is propagated through bridges / switches they don’t use routers

1)Hubs:

• It is a Physical layer device (Layer 1)
• It is Dummy Device
• It works with 0’s and 1’s (Bits)
• It works with broadcasting
• It works with shared bandwidth
• It is has 1 Broadcast Domain and 1 Collision Domain
• Collisions are identified using Access Methods called CSMA/CD and CSMA/CA

2) Broadcast Domain & collision domain

Broadcast Domain

Set of all devices that receive broadcast frames originating from any device within the set.

Collision domain

In Ethernet, the network area within which frames that have collided are propagated is called a collision domain.

Repeaters and hubs propagate collisions, LAN switches, bridges, and routers do not.

3) Type of Hubs

Active Hubs uses power supply and regenerates the data (i.e.) strengthens the signals in case of disturbances.

Passive Hubs don’t use power supply and it will not not regenerate the data (i.e.) strengthen the signals in case of disturbances. It is used only to share the physical media

Intelligent Hubs are sometimes called smart hubs. These devices basically function as active hubs, but also include a microprocessor chip and diagnostic capabilities and are useful in troubleshooting situations.

4) Switches

It is Data Link layer device (Layer 2)

Its is An Intelligent device

It works with Physical addresses (i.e. MAC addresses)

It works with fixed bandwidth

It works with Flooding and Unicast

It has 1 Broadcast domain and Number of Collision domains depends upon the number of ports.

It maintains a MAC address table

5) Types of Switches

Manageable switches

On a Manageable switch an IP address can be assigned and configurations can be made. It has a console port .

•Unmanageable switches

On an Unmanageable switch configurations cannot be made, an IP address cannot be assigned as there is no console port.