Delimiting and synchronization of data exchange is provided by Session layer.

The session layer is responsible for establishing, maintaining, and terminating sessions between applications. It provides services such as session establishment, session maintenance, and session termination.

Delimiting of Data Exchange:
- The session layer is responsible for delimiting the data exchanged between two applications. It adds headers and trailers to the data to mark the start and end of each session. This allows the receiving application to correctly identify and extract the data from the received stream.
- The session layer uses protocols such as TCP (Transmission Control Protocol) to segment the data into smaller units called segments. These segments are then transmitted over the network and reassembled at the receiving end.

Synchronization of Data Exchange:
- The session layer provides synchronization mechanisms to ensure that data is exchanged between applications in an orderly manner.
- It uses techniques such as flow control and buffering to regulate the flow of data between the sender and receiver. This helps prevent data loss and congestion.
- Flow control ensures that the sender does not overwhelm the receiver with data by regulating the rate at which data is sent.
- Buffering allows the session layer to temporarily store data until it can be processed by the receiving application. This helps to smooth out any variations in the rate of data transmission.

Example:
- In a video streaming application, the session layer is responsible for establishing a session between the video server and the client application.
- It delimits the video data into smaller segments and adds headers and trailers to mark the start and end of each segment.
- It also ensures that the video data is transmitted at a rate that can be processed by the client application, using flow control mechanisms.
- The session layer buffers the video data to compensate for any fluctuations in the network bandwidth, ensuring a smooth playback experience for the user.

In conclusion, the session layer is responsible for delimiting and synchronizing the exchange of data between applications. It adds headers and trailers to mark the start and end of each session, and uses synchronization mechanisms such as flow control and buffering to regulate the flow of data.