TCPTransmission Control Protocol

Part 1CH 23

Aseel Alturki

Based on Data Communications and Networking, 4th Edition. by Behrouz A. Forouzan, McGraw-Hill Companies, Inc., 2007

2

In Comparison with UDP

Like UDP Unlike UDPProvides process-to-process communication

Connection-oriented protocol; it creates a virtual connection between two TCPs to send data

Uses port numbers Reliable transport protocol; it uses flow and error control mechanisms

Aseel Alturki

Based on Data Communications and Networking, 4th Edition. by Behrouz A. Forouzan, McGraw-Hill Companies, Inc., 2007

3

TCP Services

UDP TCP• A process sends messages, with

predefined boundaries, to UDP for delivery

• User datagram• UDP like IP does not recognize

any relationship between the datagrams

• A process delivers data as a stream of bytes to TCP

• Segments• The two processes seem to be

connected by an imaginary tube that carries their data across the Internet

Process-to-Process communication

Stream Delivery Service:

Aseel Alturki

Based on Data Communications and Networking, 4th Edition. by Behrouz A. Forouzan, McGraw-Hill Companies, Inc., 2007

4

TCP Services (Cont..)

Stream Delivery Service (Cont..)

Aseel Alturki

Based on Data Communications and Networking, 4th Edition. by Behrouz A. Forouzan, McGraw-Hill Companies, Inc., 2007

5

TCP Services (Cont..) Stream Delivery Service (Sending and Receiving

Buffers)

Aseel Alturki

Based on Data Communications and Networking, 4th Edition. by Behrouz A. Forouzan, McGraw-Hill Companies, Inc., 2007

6

TCP Services (Cont..) Stream Delivery Service (Segments)

Aseel Alturki

Based on Data Communications and Networking, 4th Edition. by Behrouz A. Forouzan, McGraw-Hill Companies, Inc., 2007

7

TCP Services (Cont..)

Full-Duplex Communication

Connection-Oriented Service

Reliable Service

Aseel Alturki

Based on Data Communications and Networking, 4th Edition. by Behrouz A. Forouzan, McGraw-Hill Companies, Inc., 2007

8

TCP Features

Numbering System

• Byte Number

• Sequence Number: Example 23.3: Solution:

Aseel Alturki

Based on Data Communications and Networking, 4th Edition. by Behrouz A. Forouzan, McGraw-Hill Companies, Inc., 2007

9

TCP Features (Cont..)

Numbering System (Cont..)

• Acknowledgment Number

Flow Control

Error Control

Congestion Control

Aseel Alturki

Based on Data Communications and Networking, 4th Edition. by Behrouz A. Forouzan, McGraw-Hill Companies, Inc., 2007

10

Segment

Aseel Alturki

Based on Data Communications and Networking, 4th Edition. by Behrouz A. Forouzan, McGraw-Hill Companies, Inc., 2007

11

Segment (Cont..)

Aseel Alturki

Based on Data Communications and Networking, 4th Edition. by Behrouz A. Forouzan, McGraw-Hill Companies, Inc., 2007

12

A TCP Connection

In TCP, connection-oriented transmission requires three phases:1. connection establishment.2. data transfer.3. and connection termination.

Aseel Alturki

Based on Data Communications and Networking, 4th Edition. by Behrouz A. Forouzan, McGraw-Hill Companies, Inc., 2007

13

A TCP Connection (Cont..) Connection establishment:• Three-way Handshaking

Aseel Alturki

Based on Data Communications and Networking, 4th Edition. by Behrouz A. Forouzan, McGraw-Hill Companies, Inc., 2007

14

A TCP Connection (Cont..)• Three-way Handshaking (Cont..)

Aseel Alturki

Based on Data Communications and Networking, 4th Edition. by Behrouz A. Forouzan, McGraw-Hill Companies, Inc., 2007

15

A TCP Connection (Cont..) Connection establishment (Cont..):• Simultaneous Open• SYN Flooding Attack

Data Transfer:• Pushing Data• Urgent Data

Aseel Alturki

Based on Data Communications and Networking, 4th Edition. by Behrouz A. Forouzan, McGraw-Hill Companies, Inc., 2007

16

A TCP Connection (Cont..) Connection Termination• Using Three-Way Handshaking

Aseel Alturki

Based on Data Communications and Networking, 4th Edition. by Behrouz A. Forouzan, McGraw-Hill Companies, Inc., 2007

17

A TCP Connection (Cont..) Connection Termination (Cont..)• Half Close

Aseel Alturki