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How does a router know where to route packets?
When a router receives a packet, the router checks its routing table to determine if the destination address is for a system on one of it’s attached networks or if the message must be forwarded through another router. It then sends the message to the next system in the path to the destination.
How does a 2 layer switch find the destination?
Layer-2 switches perform the switching function to re-arrange the data frames from the source to a destination end by learning the MAC address of the destination node from the address table of the Switch.
How does a packet switch on a router work?
If the packet has an error, it is discarded. Otherwise, the switch looks up the MAC address and sends the packet on to the destination node. Many switches combine the two methods, using cut-through until a certain error level is reached and then changing over to store-and-forward.
How does a layer 2 switch know where to route packet?
A Layer 2 switch learns most of its information about the location of other endpoints via “listening” to ingressing frames, and when it is not aware of the location, it uses flooding and will learn from the answer. Lets say the topology is: (Host A) <–> (Switch A) <–> (Switch B) <–> (Host B).
How does host a know where to route packet?
Ideally, Host A will know the IP address of Host B (the destination that it wants to communicate to). Assuming the IP addresses of the two Hosts are in the same network, Host A uses ARP to get the mac address of the destination.
How are packets saved on an Ethernet switch?
The switch establishes a connection between two segments just long enough to send the current packet. Incoming packets (part of an Ethernet frame) are saved to a temporary memory area ( buffer ); the MAC address contained in the frame’s header is read and then compared to a list of addresses maintained in the switch’s lookup table.