Segmentation and fragmentation are two terms used in computer networking to refer to the process of breaking up data into smaller pieces to transmit over a network. While they are related, they are different concepts.
Segmentation refers to the process of dividing a large piece of data into smaller segments. This is typically done at the transport layer of the network stack, where the data is divided into segments of a fixed size. The purpose of segmentation is to enable the reliable transmission of data over a network, especially when the network has a low Maximum Transmission Unit (MTU). Segmentation ensures that data can be transmitted in smaller chunks that can be reassembled at the receiving end.
Fragmentation, on the other hand, refers to the process of breaking up a packet into smaller pieces to allow it to traverse a network with a smaller MTU. This is typically done at the network layer of the network stack, where packets are divided into smaller pieces called fragments. The fragments are then reassembled at the destination. The purpose of fragmentation is to ensure that packets can be transmitted over a network that has a lower MTU than the packet size.
In summary, segmentation refers to dividing a large piece of data into smaller segments, while fragmentation refers to breaking up a packet into smaller fragments to enable its transmission over a network with a lower MTU.