2 Tcpip Basis

7/27/2019 2 Tcpip Basis

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HUAWEI TECHNOLOGIES CO., LTD. All rights reserved

www.huawei.com

TCP/IP Basis


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HUAWEI TECHNOLOGIES CO., LTD.. All rights reserved Page 2

The communication is realized via

TCP/IP protocol stack between The

computers with different model, different

manufacturer and different OS. This

course will introduce the architecture of

TCP/IP protocol stack, the function of

each layer and data encapsulation.


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Upon completion of this course, you will be

able to :

Know architecture of OSI RM

Master architecture TCP/IP and

the function of each layer

Understand the process of TCP/IP

data encapsulation


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Chapter 1 TCP/IP Protocol Stack

Chapter 2 Data Encapsulation of

TCP/IP Protocol Stack

Chapter 3 Case analysis


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OSI Reference Model

OSI RM: Open System Interconnection Reference Model

OSI RM has the following advantages

To predigest pertinent network operation

To provide compatibility and standard interface between devices

To accelerate standardization working

Structure is separable

Easy to realize and maintenance


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OSI Reference Model

1

2

3

4

5

6

7

Low Layers: In charge of data

transmission in network.

High Layers: In charge of data

transmission between hosts.

Application layer

Presentation layer

Session layer

Transport layer

Network layer

Data link layer

Physical layer


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Functions of the Seven Layers

Application layer

Presentation layer

Session layer

Transport layer

Network layer

Data link layer

Physical layer1

2

3

4

5

6

7Provide communications

between applications

Deal with data format problems

Establish, maintain and manage sessions

Establish, maintain and

manage end to end connection

Addressing and routing

Provide link medium accessand link management

Bit flow transmission


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TCP/IP model

TCP/IP

7

6

5

4

3

2

1

Application layer

Presentation layer

Session layer

Transport layer

Network layer

Data link layer

Physical layer

5

4

3

2

1

Application layer

Transport layer

Network layer

Data link layer

Physical layer

OSI

VS


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Application layer

Transport layer

Network layer

Data link layer

Provide application program

network interfaces

Establish terminal to

terminal connection

Addressing and

route selecting

Physical media access

Binary data flow transmissionPhysical layer

HTTP, Telnet, FTP

TFTP, Ping

TCP/UDP

IP

Ethernet, 802.3, PPP

Interfaces, wires


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Communication between Layers of TCP/IP

Model and Data Encapsulation

Segment

Packet

Frame

BitPhysical layer

Transport layer

Network layer

Data link layer

Application

layer

0101110101001000010

Upper layerdata

Upper layer

dataTCP header

Upper layer

dataIP header

FCSUpper layer

dataLLC header

FCSUpper layerdata

MAC header

Host A PDU


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Data De-encapsulation

0101110101001000010

Upper layer data

Upper layer data

TCP+ upper layer data

IP+TCP+ upper layer data

LLC header+ IP+TCP+ upper layer data

Host B

Physical

layer

Network

layer

Data link

layer

Transportlayer

Application

layer


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The Function of Physical Layer

Define medium type, interface type, sign type

criterion of requirement for electric, engine, flow and function

when physical link is activation, maintenance and shutdown

between the terminal system.

Criterion of character such as voltages, data rate, maximum

transmission distance and physical connector.

LAN WAN

8

0

2

.

4

8

0

2

.

5

F

D

D

IV.35

V.24

G.703

EIA/TIA-232

8

0

2

.

3

Physical

(Bits,signals,

clocking)


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Physical layer medium and device

Physical layer medium

Coaxial cable

Twisted-pair

Fiber

Wireless radio

Physical layer device

Repeaters, HUB


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The Function of Data Link Layer

LLC sub-layer

MAC sub-layer

MAC Sub-layer : Media Access Control Sub-Layer

Appoint that how to transmit data packet via physical line and

communicate with physical layer

LLC Sub-layer: Logic Link Control Sub-layer

Distinguish protocol types, encapsulate the data and transmit via

network

Application layer

Transport layer

Network layer

Data link layer

Physical layer


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Protocols of Data Link Layer

LAN WAN

8

0

2

.

4

8

0

2

.

5

F

D

D

I

802.2 LLCFrame

Relay PPP

V.35

Dial

onDemand

SDLC HDLC

V.24

G.703

EIA/TIA-232

8

0

2

.

3

Data link layer LAN, WAN protocol

Physical

(Bits,signals,

clocking)

Data Link

(Frames)

Data link layer device

Ethernet switch


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Data Link Layer Address

MAC address is composed of 48 bits. The vendor ID of Huawei

products is 0x00e0fc.

00e0.fc01.2345

24 bits 24 bits

00e0.fc01.2345

Rom

Ram

Vender Code Serial Number


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The Function and Device of Network Layer

Network layer

Data link layer

Physical layer

Network layer

Data link layer

Physical layer

Network layer

Data link layer

Physical layer

B

Router A Router B Router C

A

CD

EApplication layer

Transport layer

Network layer

Data link layer

Physical layer

Function

Data forwarding in the different networkDevice

Router, layer 3 swtich

Host A

Host B


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Protocols of Network Layer

Protocols of Network layer

8

0

2

.

4

8

0

2

.

5

F

DD

I

802.2 LLCFrame

RelayPPP

V.35

Dial

on

Demand

SDLC HDLC

V.24

G.703

EIA/TIA-232

8

0

2

.

3

IP/ICMP/ARP/RARP

Physical(Bits,

signals,clocking)

Data Link

(Frames)

Network

(Packets)


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Network Address

IP Address

Network address identifies a device in the network layer

uniquely

Network address include two parts

Network ID

Host ID

Host IDNetwork ID

8.2.4810.


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The Function of Transport Layer

Segment upper layer data

Set up end to end connection

Transmit data from end to end

ensure the reliability of the data

transmission


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Protocols of Transport Layer

Physical

(Bits,signals,

clocking)

Data Link

(Frames)

80

2

.

4

80

2

.

5

F

D

D

I

802.2 LLCFrame

RelayPPP

V.35

Dial

on

Demand

SDLC HDLC

V.24

G.703

EIA/TIA-232

80

2

.

3

Network(Packets)IP

Transport

(Segments)UDPTCP


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Main Protocols of Transport Layer

TCP

Connection-oriented

Reliable

Suit the application with

high reliability

High cost

UDP

Connectionless

Trustless

Suit the application that

concerns transmission

efficiency

Reliability depends on

application


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The Function of Application Layer

Provide user interfaces and deal with specify applications

Provide data encryption, decryption, compression

and decompression.

Specify the standards of data presentation.


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Protocols of Application Layer

Physical

(Bits,signals,

clocking)

Data Link

(Frames) 80

2

.

4

8

0

2

.

5

F

D

D

I

802.2 LLCFrame

Relay PPP

V.35

Dial

onDemand

SDLC HDLC

V.24

G.703 EIA/TIA-232

8

0

2

.

3

Network

(Packets)IP

Transport

(Segments)UDPTCP

Application

(Data)TFTP SNMP RIP DNS Radius

FTP TELNET HTTP

SMTP/POP3 DNS


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Chapter 1 Internet Connection of

TCP/IP

Chapter 2 Data Encapsulation of


Chapter 3 Case Analysis


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The Encapsulation Process of TCP/IP Protocol Stack

User dataApp header

User dataTCP headerIP header

TCP Segment

IP Packet

46-1500 bytes

14B 20-64B 20-60B 4B

Ethernet Frame

Application

TCP

IP

Application drive

user data

User dataTCP header

Ethernet traileruser dataTCP headerIP headerEthernet header


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TCP Segment

16b 16b 32b 32b 64b

Source

Port

Dest.

Port...Seq Num Ack Num Option

14B 20-60B 20B-60B 4B

Ethernet Frame

Ethernet trailerUser dataTCP headerIP headerEthernet header


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IP Packet

versionMessage

length Service type Total length

identification Flag Chip offset

Time to live protocol Message header checksum

Source IP address

Destination IP address

IP options

0 15 16 31

20B

Fixed

message

header

14B 20-60B 20B-60B 4B

Ethernet trailerUser dataTCP headerIP headerEthernet header


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Issue of IP Fragment

Fragment principle: comparing with data length and MTU, if the former islarger than the latter, fragment is needed.

HostHost

MTU MTU

Fragment on sending end

Fragment on the middle routers

IP

packet


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Ethernet Frame

Ethernet_II

Length/Type value meaning

Length/T > 1500

Length/T


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Chapter 1 Internet Connection of

TCP/IP

Chapter 2 Data Encapsulation in


Chapter 3 Case Analysis


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Case Analysis (1)


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Case Analysis (2)

Source

MAC

Destination

MAC

Type


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Case Analysis (3)

Source IP DestinationIP


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Case Analysis (4)

Source port

Destination port


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Summary

What layers does OSI RM divide into?

Whats the function of each layer of

TCP/IP protocol stack?

whats the process of message

encapsulation and de-encapsulation in

TCP/IP protocol stack?

Whats the difference between MAC

address and IP address?


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2 Tcpip Basis