2Next hop how to send the IP datagram 3Interface what is the output port Next

2next hop how to send the ip datagram 3interface what

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2.Next hop: how to send the IP datagram? 3.Interface: what is the output port? Next hop and interface column can often be summarized as one column Routing tables are set so that datagrams gets closer to its destination . Delivery with routing tables:
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37 Processing of an IP datagram at a router 1.IP header validation 2.Process options in IP header 3.Parsing the destination IP address 4.Routing table lookup 5.Decrement TTL 6.Perform fragmentation (if necessary) 7.Calculate checksum 8.Transmit to next hop 9.Send ICMP packet (if necessary) Routing table manipulations with ICMP: When a router detects that an IP datagram should have gone to a different router, the router (here R2) - forwards the IP datagram to the correct router - sends an ICMP redirect message to the host Host uses ICMP message to update its routing table
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