Arouter may have to fragment a packet when forwarding it from one medium to another medium that has a smaller

MTU, i.e., Maximum Transmission Unit

Explanation:

Fragmentation

The process of breaking the packets into smaller fragments of data packets with header on each and every packet.

Fragmentation at the router is done to ensure that fragment is of the size small enough to fit in the MTU while entering different network.

MTU:

Maximum Transmission Unit abbreviated as MTU can be defined as the greatest number of bytes is the largest number of bytes that a single data packet can accommodate on a specific data link for communication.

The end-to-end effective size of the MTU is decreased while using the encryption, encapsulation, etc protocols.

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