Computer Networks Premium Lecture Notes (All Units) - Suba Edition

Computer Networks Premium Lecture Notes, Prepared by Thenmozhi. Specially for Computer Science Engineering and Information Technology. Syllabus Covered based on Anna University B.E CSE and B.Tech I.T.

Content :

UNIT-1

NETWORK ARCHITECTURE LAYERS

Computer network

Point to point

Multiple point

Switched network

Channels

1. Request or replay channel
2. Message stream channel

Communication

1. Simplex
2. Half duplex
3. Full duplex

Client or server

Protocols

Types

1. TCP
2. UDP

Topology

NETWORK ARCHITECTURE

Layering and protocols

Interfaces

Protocols graph

OSI ARCHITECTURE

Function of layers

1. Physical layer
2. Data link layer
3. Network layer
4. Transport layer
5. Session layer

Dialog control

Presentation layer

Translation

Application layer

PHYSICAL LINKS

Transmission media

1. Guided media
   1. Twisted pair
   2. Co-axial cable
   3. Fiber optic cable
   4. Unguided media

CHANNEL ACCESS ON LINKS

Multiplexing

Application

Types

1. FDMA (frequency division multiple access)
2. TDMA (time division multiple access)
3. CDMA (code division multiple access)

ERRORS

1. Single error
2. Burst error
3. Burst error

REDUNDANCY

ERROR DETECTION TECHNIQUE

1. Parity check
2. Simple parity check
3. Two dimensional parity check

Vertical redundancy check

Cyclic redundancy check

Checksum

Error correction

Link level flow control

1. Flow control
   1. Stop and wait
   2. Sliding window
   3. Error control
      1. Stop and wait
      2. Sliding window
         1. Go back ARQ
         2. Selective reject RQ

Flow control

1. Normal operation
2. Lost and damaged frame
3. Lost acknowledgement
4. Delayed acknowledgement

Piggy packing

FRAMING

Classification

1. Byte oriented protocol
   1. PPP
   2. Sentinel approach protocol
   3. Bit oriented protocol
      1. SDLC (synchronous data link control)
      2. HDLC (high level data  link control )
      3. LAP (link approach protocol)
      4. LAN (local area network)

UNIT-2

Medium access

CSMA

Inter frame space

Token ring

Ring interface

Two modes

1. Listen mode
2. Transmit mode

Token passing

Frame format

Token format

FDDI (fiber distributed data interface)

Access method

FDDI layer

Frame types

Wireless LAN

Technologies

1. Bluetooth
2. Wi-Fi
3. Wi-Max
4. SG cellular wireless

Bridges and LAN switches

Types

1. Transport bridge
2. Source routing bridge

UNIT-3

Switching

1. Circuit switching
2. Packet switching
3. Message switching

Global addressing

Address resolution protocol (ARP)

Client server arch

Queuing discipline

FIFO

Routing algorithm

1. Next hop routing
2. Network specific routing
3. Host specific routing

Link state routing

DIJIKSTRA ALGORITHM

IPV6

Transition from IPV4 to IPV6

Dual stack

Tunneling

Header transition

 IPV6 header

BGP (border gateway protocol)

BGP router

Conjetion avoidance in network layer

Two catagories

1. Open loop
2. Close loop

DHCP frame format

DHCP messages

UNIT-4

UDP (User Datagram Protocol)

UDP message queue

TCP

TCP segment format

Connection

State transition diagram

Adaptive flow control

Receiver window

Silly window syndrome

Syndrome created by Rx

Syndrome created by sender

Multiplication decrease

Four cases of congestion

QOS

Method of QOS

1. Scheduling
   1. FIFO queuing
   2. Priority queuing
   3. Weighted fair queuing
   4. Traffic shaping
      1. Leaky bucket
      2.  Token bucket
      3. Admission control
      4. Resource reservation

UNIT-5

E-mail

Receiving mail

User agent

Services of UA

User agent type

MIME (multipurpose internet mail extensions)

MIME header

Content type

Content transfer encoding

MTA (mail transfer agent)

Phases in mail transfer

Mail\delivery

IMAP (internet mail access protocol)

 POP (post office protocol)

HTTP (hypertext transfer protocol)

Request message

Request line

Request type

URL defines

1. Method
2. Host compute
3. Port
4. Path

Header

1. General header
2. Request header
3. Response header
4. Entity header