SWITCH What is a Switch ? Switch is a network device which is used to enable the connection Establishment and connection termination on the basis of need. Switch is operated on The Data link layer. In this packet filtering is available. It is a type of full duplex Transmission mode and it is also called an efficient bridge. How does switch perform forwarding function ? Switches use a relatively simple concept to forward a frame. Is Find the destination MAC address of the incoming frame in the CAM table and if the address is available in the table, forward the frame from the port which is connected with the destination MAC address otherwise forward the frame from all ports except the port on which it arrived. Explain Flooding ? Flooding is a non-adaptive routing technique when a data packet arrives at a router, it is sent to all the outgoing links except the one it has arrived on. Flooding is a way to distribute routing protocols updates quickly to every node in a large network PC which is connected to switch port 23. The switch has learned the mac address of the PC. The port is now shutdown. Will the switch retain the mac address ? In layer 2 domain do we need ip address for communication? In short, no... you don't need IP addresses to connect machines in the same network. There are several examples of protocols like this like: IPX or Banyan protocols. Computers in the same subnet actually do communicate directly with each other using the MAC address. It actually starts by sending out an ARP request (ARP = Address Resolution Protocol) which means it shouts out "Who has the address X.X.X.X?"... and whoever has that address replies and from that point on, they continue to talk to each other directly. What is Mac address table ? The MAC address table is where the switch stores information about the other Ethernet interfaces to which it is connected on a network. The table enables the switch to send outgoing data (Ethernet frames) on the specific port required to reach its destination, instead of broadcasting the data on all ports (flooding).
