TCP/IP Protocol Suite

TCP IP Protocol Suite is the foundation of TCP/IP model. OSI Reference model is a theoretical model. TCP/IP Model is the implemented model.

Today in this tutorial we will learn about TCP/IP protocol suite in more detail. We have explained each and every protocol and it’s function used in TCP/IP Model.

Questions based on TCP/IP Model are generally asked in GATE CSE and UGC NET exam. This tutorial will be beneficial for students specially for GATE CSE 2022 Aspirants. Students are requested to read this TCP/IP Protocol Suite Tutorial completely.

What is TCP/IP Protocol Suite ?

TCP/IP Protocol Suite refer to a suite of data communication protocols. TCP/IP have two zones protocol that composes the suite.
Protocols used at each layer of TCP/IP Model are as shown in this Figure.

TCP/IP protocol suite has five layers as shown in the figure.

Different types of protocols used at different layers of TCP/IP Protocol suite as shown in the figure are explained as follows:

Example Data Link Layer Protocols

At physical and data link layer TCP IP protocol suite does not define any specific protocol. It supports all standard protocols.
A network in TCP/IP interwork can be a LAN( local area network ) or a wide area network.
Examples of Data Link Layer Protocols are PPP, ARP, OSPF

Network Layer Protocols

At the network layer or internetwork layer, TCP/IP protocol support Internetworking Protocols(IP) . which provides basic packet delivery services for all the TCP/IP networks.

Since the basic functionalities of Internetworking Protocol (IP) are as follows

It defines the datagram which is the basic unit of the data transmission on the internet. IP support the data in the packet each of which is known as datagram and it is transported separately.
The datagram can travel along the different route and arrive out of sequence. And even datagram may be received duplicated.
IP protocol does not keep the track of the route or reordering the datagram.
IP protocol defines the internet addressing scheme which is system of logical host addresses.
IP protocol is responsible for moving the data between the network layer and host to host transport layer.
Internet protocol route the datagram to the remote host.
IP protocol is also responsible for fragment and reassembles the datagram.
Internetworking protocol also contain four supporting protocols named as ARP, RARP, BGP, IGMP and ICMP

What is ARP ?

ARP is known as Address Resolution Protocol. This is used at both Network layer and data link Layer.
Address resolution protocol is used to associate an IP address with a Physical address.
ARP is used to find the physical address of a node when the logical address is known.

What is RARP ?

RARP is known Reverse address resolution protocol (RARP). This is used at Network Layer.
RARP is used to find the internet address or logical address of a host when its physical address is known.
RARP is generally used when a computer is connected first time to the network.

What is ICMP ?

ICMP is known as Internet Control Message Protocol. ICMP is a network layer protocol.
ICMP protocol proved a mechanism by which is used by a host and gateway to send notification of datagram related problem back to the sender. ICMP send query and error reporting message

What is IGMP ?

IGMP is known as Internet Group Management Protocol (IGMP). IGMP is a Protocol used at Network Layer.
The internet group management protocol is a protocol which is used by a host and its adjacent routers on IP Network to establish multicast group membership.

Transport Layer Protocols

Transport layer provides two protocols in TCP/IP suite. These protocols are TCP and UDP.
UDP and TCP are the protocols which are responsible for delivery of the entire message from a process to another process.

What is TCP ?

TCP is known as Transmission Control Protocol. TCP is a transport layer protocol.
TCP is a reliable stream transport protocol. In this context, the meaning of the term stream is connection oriented.
A connection must be established between both end of transmission before either end can transmit the data.
At the sending end of each transmission, TCP divides a stream of data into a smaller unit which is known as the segment. Each segment has a sequence number for reordering at the receiver side.
Segments are carried across the internet inside the IP datagram.
At receiving end TCP collect each datagram as it comes in and reorders the transmission based on sequence numbers.

What is UDP ?

UDP is known as User Datagram Protocol. UDP is a Transport Layer Protocol.
User datagram protocol is an alternative to TCP protocol.
Unlike TCP UDP is connectionless. UDP does not acknowledge or guarantee delivery and does not provide sequencing of the packet.
The application itself must process any error and check for reliable delivery.
UDP is specially used for real-time audio and video where packets are simply ignored. Because there is time to retransmit.

Application Layer Protocols

Application Layer is the top most layer of TCP/IP Model. It act an interface for user. The most widely used and implemented Application Layer protocols are as follow

File Transfer Protocol (FTP)

FTP performs basic interactive file transfer between the protocol.

Telnet

Telnet enables users to execute terminate the session between remote host. It provides remote login facility.

Simple Mail Transfer protocol(SMTP)

SMTP support basic email delivery services.

Hypertext transfer protocol

HTTP supports the low overhead transport of files which consist a mixture of text and image.

Domain Name Service( DNS)

DNS is also known as name services. This basically maps the IP address to the name assigned to the device.

Routing Information Protocol(RIP)

RIP is used by the network device to exchange routing information.

Simple Network Management Protocol (SNMP)

This is a protocol which is used to collect the management information from the network devices.

Network File System (NFS)

NFS is system developed by the Sun Microsystems that enable the computer to mount drive on remote host and operate them as if they are on local drives. Later we will study these protocols in more details.

Conclusion and Summary

We have explained TCP/IP Protocol suite in this tutorial in detail. I hope this tutorial will be helpful to you in study of various protocols of TCP/IP Model.