List at least five tasks a layer performs. Could one (or more) of these tasks could be performed by multiple layers?

Transport layer:

- data packets are segment to smaller chunks.

- gives sequence number to segment.

- identifies the source and destination port number.

- initiates data transmission between nodes.

- rearrange and identifies the application, the transmitted data is meant for.

Explanation:

The transport layer is the fourth layer in the OSI network model. Protocols like TCP and UDP are found in this layer. It segment data packets and for a connection oriented protocol like TCP, it creates an established session between source and destination host (the session layer can also do this, but it is more defined in the transport layer).

The network and data-link layer can also transmit data packets.