Transport Layer Responsibilities

Transport Layer Responsibilities

1. Tracking Individual Conversations

   • At the transport layer, each set of data flowing between a source application and a destination application is known as a conversation and is tracked separately

2. Segmenting Data and Reassembling Segments

   • It is the transport layer responsibility to divide the application data into appropriately sized blocks.
     • Depending on the transport layer protocol used, the transport layer blocks are called either segments or datagrams.

3. Add Header Information

   • The transport layer protocol also adds header information containing binary data organized into several fields to each block of data.
     • It is the values in these fields that enable various transport layer protocols to perform different functions in managing data communication.

4. Identifying the Applications

   • The transport layer must be able to separate and manage multiple communications with different transport requirement needs.
     • To pass data streams to the proper applications, the transport layer identifies the target application using an identifier called a port number

5. Conversation Multiplexing

   • The transport layer uses segmentation and multiplexing to enable different communication conversations to be interleaved on the same network.