Domain is nothing but a logical networking space with different networking devices operating in it.

Broadcast Domain:

• It is a networking space till where the broadcast packets can travel sent by a system within a domain.
• It will be received by all the system within that domain.
• Broadcast domains are usually separated by a router, as it does not forward the broadcast packet.
• Switch has a single BD without VLAN and with VLAN, each VLAN will be a separate BD.
• If BD is large, users have less bandwidth as broadcast packets need to be processed which will slow the network performance.

Collision Domain:

• It a networking space where data packet can collide with one another being sent on a shared medium.
• If two system sends a data at the same time, till what area data may get hit and collision may happen in a network, that complete area is collision domain.
• Collision is directly proportional to number of devices in the collision domain.
• An increased number of collision will result in low quality of network because hosts spend a large amount of time for packet processing and retransmission.
• In switch, bridge and router, each port is a separate CD.

BD : 2 (separated by Router)

CD : 5 ( as each port on switch is separate CD)

Categories: Networking