UDP & TCPUDP & TCP

By: Muhammad Hanif

User Datagram ProtocolUser Datagram Protocol&&

Transmission Control ProtocolTransmission Control Protocol

Quote of the day……Quote of the day……Many of life's failures are people who did not realize how close they were to success when they gave up.

~Thomas Edison

Have a blessed day!

Transport ProtocolsTransport Protocols Provide logical

communication between application processes running on different hosts

Run on end hosts ◦ Sender: breaks application

messages into segments, and passes to network layer

◦ Receiver: reassembles segments into messages, passes to application layer

Multiple transport protocol available to applications◦ Internet: TCP and UDP

UDPUDP

BS IT & BS CSBy: Muhammad Hanif

User Datagram User Datagram ProtocolProtocol

Position of UDP in the Position of UDP in the TCP/IP protocol suiteTCP/IP protocol suite

User Datagram ProtocolUser Datagram ProtocolUDP is an end-to-end or transport

protocol that allows an application program to serve as the end-point of communication

UDP CharacteristicsUDP CharacteristicsEnd-to-endConnectionlessMessage-oriented

◦ Each UDP message must fit within one IP datagram

◦ UDP message can be lost, duplicated, or corrupted

◦ Suitable for applications that can tolerate delivery errors

◦ One-to-one, one-to-many

E.g. Internet Telephony, Conference Call

UDP FormatUDP Format

UDP Format DetailUDP Format Detail Source Port/Destination Port: A port Virtual circuit

between two communicating processes on two different computers or devices

The source port is the port on the sending device. The destination port is a TCP port on a receiving

device that corresponds with the source port on the sending device

Length: contains information about the length of the frame

Checksum: This field is used to detect errors over the entire user datagram (header plus data).◦ Placed in the frame by the sending station. ◦ The recipient also calculates the checksum and compares

its calculation with the value in the checksum field.

Encapsulation and Encapsulation and DecapsulationDecapsulation

TCPTCP

BS IT & BS CSBy: Muhammad Hanif

Transmission Transmission Control ProtocolControl Protocol

Quote of the day……Quote of the day……Be noble minded! Our own heart,

and not other men's opinions of us, forms our true honor.

- Johann Friedrich Johann Friedrich was a German

anatomist.

Position of TCP in the Position of TCP in the TCP/IP protocol suiteTCP/IP protocol suite

TCP FeaturesTCP FeaturesReliable, in-order delivery (TCP)

◦Connection Oriented◦Discarding of corrupted packets◦Retransmission of lost packets◦Flow control

Establishing a TCP Establishing a TCP ConnectionConnectionThree-way

handshake to establish connection◦Host A sends a SYN

(open) to the host B◦Host B returns a SYN

acknowledgment (SYN ACK)

◦Host A sends an ACK to acknowledge the SYN ACK

TCP segment formatTCP segment format

Control FieldsControl Fields