Q. Show Upper Layers of tcp-ip model?

The Session Layer

- The Session layer allows two parties to hold ongoing communications called a session across a network.

- Not found in TCP/IP model

- In TCP/IP its characteristics are offered by the TCP protocol.(Transport Layer)

The Presentation Layer

The Presentation Layer manages data format information for networked communications. This is complete by converting data into a generic format that could be understood by both sides.

- Not found in TCP/IP model

- In TCP/IP this function is offered by the Application Layer.

Example - External Data Representation Standard (XDR)

MIME (Multipurpose Internet Mail Extensions)

The Application Layer

The Application Layer is the highest layer of the reference model. It offers a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directly.

- MHS, DS, OSI- FTAM, VT, CMIP

TELNET, TCP/IP- FTP, SMTP, DNS, SNMP

- Even though the notion of an application process is common to both their approaches to constructing application entities are different.