Notes on IP fragmentation:!The source host or any routerin the path between source and destination can fragment an IP packet.!Reassembly of the packet is done at the destination host since the network treats each fragment asindependent unit!There is no guarantee on the path these fragments will be taking!The host or the router that fragments a packet must change the values of the1.Flag field2.Fragment offset field3.Total length fieldAll other fields (including the identification field) remain the same. Of course the header checksumneed to be calculated for every fragment!A fragmented IP packet may be fragmented (several times) itself if it passes a network with a smaller"MTU"!All fragments (and fragments of a fragment) will have the same identification field, which is the sameas that used in the original IP packet. The identification number allows the destination to reassemblethe packet. Identification numbers for different packets (from the same source) are different!
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