Fragmentation Problems

IP supports a maximum length of 65,536 bytes for an IP packet; however, most data-link layer protocols support a much smaller length, called a maximum transmission unit (MTU). Based on the supported MTU, it might be necessary to break up (fragment) an IP packet to transmit it across a particular data-link layer media type. The destination then would have to reassemble the fragments back into the original complete IP packet.

The problem with fragmentation is that it requires additional CPU and memory resources on devices performing fragmentation. This is not to say that the actual source and destination will perform the fragmentation. For example, assume that the source and destination are on a Token Ring network with an ...

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