Contents
What does a router do if it receives a packet with destination IP that is not in its routing table?
If router is not present in routing table of router . Router will just drops the packet .
Does a router forward packets?
Routers are specially configured systems with multiple physical interfaces that connect the router to more than one local network. Therefore, the router can forward packets beyond the home LAN, regardless of whether the router runs a routing protocol.
How does a router determine the best route?
A primary function of a router is to determine the best path to use to send packets. To determine the best path, the router searches its routing table for a network address that matches the destination IP address of the packet.
What will a router do if it receives a packet that has errors?
If a packet error occurs, TCP (Transmission Control Protocol) will resend the same information repeatedly, in hopes the data will eventually reach the destination without any problems, while UDP (User Datagram Protocol) will keep trucking forward even when packets fail to reach their destination.
What happens when a router forwards data packets from one network to another network?
What happens when a router forwards data packets from one network to another network? It encapsulates the packet in an Ethernet frame and then transmits the frame over the Ethernet network.
Which feature allows the router to know where to forward a packet it receives?
destination IP address
When the router receives a packet, it looks at its IP header. The most important field is the destination IP address, which tells the router where the packet wants to end up.
How is a packet forwarded to a router?
Router R1 in Figure 6.8 receives a packet with destination address 192.16.7.14. Show how the packet is forwarded. Solution The destination address is 11000000 00010000 000001110 0001110. A copy of the address is shifted 28 bits to the right.
When does multicast routing not forward a packet?
Multicast routing does not forward a packet unless the source of the packet passes a RPF check. Once a packet passes this RPF check, multicast routing forwards the packet based only upon the destination address.
How does a router find an IP address?
Once router remove L2 information it looks for Layer 3 information available on packet that is source and destination IP address. For moving L3 packet between interfaces, router checks destination address and finds longest-prefix match in IP routing table to find outgoing interface.
Why does my router hang when I do packet debugging?
Packet debugging triggers process switching of the multicast packets, which is CPU intensive. Also, packet debugging can produce huge output which can hang the router completely due to slow output to the console port.