What is Session Layer
Session layer has responsible for managing, establishing, synchronizing and terminating all sessions in between local and remote application.
Functions of Session Layer
- It allows dialoging control, and it helps to make communication in between in half-duplex or full-duplex.
Steps to build a session connection with two peer session services users, Follow these steps –
- Getting to map session address with shipping address
- Choose needed transport quality of service parameters.
- Session parameters are getting negotiation.
- Determine every session connections.
- Transfer limited user data.
- Data transmission cycle
- This layer enables with token management because it helps to protect two lines from getting similar most critical operation at once.
- Synchronization: Session layer enables with a process for attaching checkpoint which are worked as synchronization points into the data. Due to this synchronization, all errors can be identified, and all data is getting re-synchronized, and ends of the messages are not cut prematurely, as well as preventing loss of data.
Protocols of Session Layer
Session layer is used different types of protocols; below explain each one –
Examples of Session Layer
These protocols are also known as examples of session layer protocols; such as-
Remote procedure call protocol (RPC): RPC protocol is used for requesting a service one computer to another computer system over the network without knowing any information of network.
Point-to-Point Tunneling Protocol (PPTP): This protocol is used for establishing Virtual Private Network (VPN) tunnels in between other public network.
Session Control Protocol (SCP): SCP protocol is used to make light duty connections from single TCP connections, and those lightweight connections can be active at once..
Session Description Protocol (SDP): This protocol is used to define all parameters for transferring all multimedia in between two end systems.
AppleTalk Data Stream Protocol (ADSP): ADSP is a connection oriented protocol, and it helps to transfer full-duplex streams of data over the AppleTalk internet.
AppleTalk Session Protocol (ASP): This protocol allows multiple ASP workstation applications for building the session along with same server at once.
Internet Storage Name Service (iSNS): This protocol deals with automation of discovery and management of iSCSI devices over a TCP/IP storage network. It keeps all information like as their IP addresses, iSCSI node names, and portal groups.
Other Session Protocols are:-
- Call Control Protocol for Multimedia Communication
- OSI session-layer protocol (X.225, ISO 8327)
- Layer 2 Forwarding Protocol
- Layer 2 Tunneling Protocol
- Network Basic Input Output System
- Password Authentication Protocol
Design Issues with Session Layer
- To enable all machines to build sessions in between them in seamless nature
- To offer increased services to end user
- To handle dialog control
- To offer several services like as Token management and Synchronization.