Lesson 1

Ethernet

YuanApplication Engineer / iConnectivity Group (ICG)

2014.10.28

1

Outline

• Ethernet Technology– History and Standards

– Topology

– Hardware Specifications

– Access Method

– Types of Ethernet

• OSI module and TCP/IP protocol suite

• Connecting Device

• Hands On

2

Ethernet Technology

3

History and Standard

• Computer networking technology for Local

Area Networks(LANs)

• Xerox PARC Developed in 1973

• Commercially introduced in 1980

• Standardized in 1983 as IEEE 802.3

• Ethernet was clearly the dominant network

technology by the end of the 1980s.

4

Topology

5

Hardware Specifications(1/2)

• Signal: Baseband

• Media

– Coaxial Cable

– Twisted Pair

– Optical Fiber

6

Hardware Specifications(2/2)

• Connector

– Coaxial Cable: DB15, BNC etc.

– Twisted Pair: RJ-45 (not RJ-11)

– Optical Fiber: ST, SC, LC etc.

DB15 BNC

RJ-45 RJ-11

ST SC LC7

Access Method(1/2)

• Carrier Sense Multiple Access, CSMA

8

Access Method(2/2)

• Carrier Sense Multiple Access with Collision

Detection, CSMA/CD

9

Tp

~2Tp

Types of Ethernet(1/2)

100 Base-TX

X Y Z

X:bandwidth

Y: signal

Z: media type

transmission distance

Ethernet Fast Ethernet Gigabit Ethernet 10-Gigabit Ethernet

IEEEstandard

802.3 802.3u 802.3z 802.3ae

Bandwidth 10Mbps 100Mbps 1Gbps 10Gbps

Access method

CSMA/CDCSMA/CD in Half DuplexCentral Switch in Duplex

Central Switch in Duplex

Topology Bus , Star Star Star Star

TransmissionMedia

Coaxialcable

Twist pair / Fiber

Twisted pair /Fiber

Twisted pair / FiberFiber

10

Types of Ethernet(2/2)

Topology Maximum segment length Transmission Media

10Base-5 Bus 500m Coaxial cable (thick) 50 ohm

10Base-2 Bus 185m Coaxial cable (thin) 50 ohm

10Base-T Star 100m Twisted pair 100 ohm

10Base-F Star 2000m Fiber

100Base-TX Star 100m STP

100Base-T4 Star 100m UTP

100Base-FX Star 100m Fiber

1000Base-SX Star 550m Fiber

1000Base-LX Star 5000m Fiber

1000Base-CX Star 25m STP

10GBase-S Star 300m Multi Mode Fiber

10GBase-L Star 10000m Single Mode Fiber11

Twisted-pair cablesName

Typical construction

Bandwidth Applications Notes

Level 1 0.4 MHz Telephone and modem linesNot described in EIA/TIA recommendations. Unsuitable for modern systems.

Level 2 4 MHz Older terminal systems, e.g. IBM 3270Not described in EIA/TIA recommendations. Unsuitable for modern systems.

Cat.3 UTP 16 MHz 10BASE-T and 100BASE-T4 EthernetDescribed in EIA/TIA-568. Unsuitable for speeds above 16 Mbit/s. Now mainly for telephone cables

Cat.4 UTP 20 MHz 16 Mbit/sToken Ring Not commonly used

Cat.5 UTP 100 MHz 100BASE-TX & 1000BASE-T Ethernet Common in most current LANs

Cat.5e UTP 100 MHz 100BASE-TX & 1000BASE-T EthernetEnhanced Cat5. Same construction as Cat5, but with better testing standards.

Cat.6 UTP 250 MHz 10GBASE-T EthernetMost commonly installed cable in Finland according to the 2002 standard. SFS-EN 50173-1

Cat.6a U/FTP, F/UTP 500 MHz 10GBASE-T EthernetAdds cable shielding. ISO/IEC 11801:2002 Amendment 2.

Cat.7 F/FTP, S/FTP 600 MHzTelephone, CCTV, 1000BASE-TX in the same cable. 10GBASE-T Ethernet.

Fully shielded cable. ISO/IEC 11801 2nd Ed.

Cat.7a F/FTP, S/FTP 1000 MHzTelephone, CATV, 1000BASE-TX in the same cable. 10GBASE-T Ethernet.

Uses all four pairs. ISO/IEC 11801 2nd Ed. Am. 2.

Cat.8.1 U/FTP, F/UTP 1600-2000 MHzTelephone, CATV, 1000BASE-TX in the same cable. 40GBASE-T Ethernet.

In development.

Cat.8.2 F/FTP, S/FTP 1600-2000 MHzTelephone, CATV, 1000BASE-TX in the same cable. 40GBASE-T Ethernet.

In development.

12

OSI module

TCP/IP protocol suite

13

Overview(1/2)OSI

• Theoretical model

• Has seven architectural

layers

• Protocol-independent

standard

TCP/IP• Model around which

internet is developed

• Has four architectural

layers

• Protocol-dependent

standard

14

Overview(2/2)

15

Layer 1: Physical Layer

• Media interface

• Signal strength

• Encoding (0 or 1)

• Transmission mode (simplex, half-duplex, full-

duplex mode)

• Physical Topology (star, bus, ring)

• Line configuration (point-to-point, multipoint

configuration)

16

Layer 2: Data Link Layer(1/2)

• Access control

• Error detection (FCS/CRC)

• Physical addressing

L2 Ethernet Frame 64-1518 bytes

12B

GAP

7B 1B 6B 6B 2B 4B46-1500B

Preamble SDDestination

MAC

Source MAC

Type Data Pad FCS

Ethernet Frame format

17

Layer 2: Data Link Layer(2/2)

MAC address format

LSB

4A:30:10:21:10:1A

A=1010

unicast

47:20:1B:2E:08:EE

7=0111

multicast

FF:FF:FF:FF:FF:FF

broadcast

18

Ethernet II special bit

IEEE 802.3 special bit

Layer 3: Network Layer(1/3)

• End to end Delivery

• Routing

• Fragmentation/sequencing for MTU

• Logical addressing

Technology Maximum Transmission Unit

Ethernet 1500 Bytes

FDDI 4352 Bytes

X.25 1600 Bytes

ATM 9180 Bytes

802.11 2272 Bytes

19

Layer 3: Network Layer(2/3)

Private IPClass A 10.0.0.0 – 10.255.255.255

Class B 172.16.0.0 – 172.31.255.255

Class C 192.168.0.0 – 192.168.255.255

• IP address

Public IP

20

Layer 3: Network Layer(3/3)

• IP Packet format

IP Header IP Payload

21

Layer 4: Transport Layer

• Process-to-process delivery

• Service-point addressing

• Flow control

• Error recovery

• Connection control

• Fragmentation/Sequencing of data

22

Layer 5: Session Layer• Dialog control

• Synchronization

Layer 6: Presentation Layer• Translation (ASCII, JPEG)

• Encryption

• Compression

Layer 7: Application Layer• Network virtual terminal

• File transfer, access, and management(IE, Outlook)23

L7 L4 L3

24

Connecting Device

25

Layer 1 Device(1/3)

• Physical layer device

• Receives and retransmits

• Repeater and hub

– 1000Base-CX needs a repeater or hub per 25m

– Show as the table at pg.11

26

Layer 1 Device(2/3)

• Repeater

– Receives a signal and retransmits it at a high level

or higher power, or onto the other side of an

obstruction, so that the signals can cover longer

distances

27

Layer 1 Device(3/3)

• Hub

– Connecting multiple ethernet devices together and

making the act as a single network segment

– Has multiple I/O ports, repeats the input signal at

the output of every port

– Participate in collision detection, forwarding a jam

signal to all ports if it detects a collisionhub

abandon abandon abandonreceive

28

Layer 2 Device(1/3)

• Physical and data link layer device

• Bridge and layer 2 switch

29

Layer 2 Device(2/3)

• Bridge

– Connects multiple network segments

– Decides the message to which LAN

Bridge

A B C D

71:2B:13:45:61:41 71:2B:13:45:61:42 64:2B:13:45:61:12 64:2B:13:45:61:13

1

2 3

4

30

LAN 1 LAN 2

Layer 2 Device(3/3)

• Layer 2 Switch

• Learns, Filters and forwards

• No collision, only bandwidth sharingL2 Switch

A B C D

71:2B:13:45:61:41 71:2B:13:45:61:42 64:2B:13:45:61:12 64:2B:13:45:61:13

1

2 3

4

MAC address port

-------------------------------------------

MAC address port

-------------------------------------------

71:2B:13:45:61:41 1

MAC address port

-------------------------------------------

71:2B:13:45:61:41 1

64:2B:13:45:61:13 4

MAC address port

-------------------------------------------

71:2B:13:45:61:41 1

64:2B:13:45:61:13 4

71:2B:13:45:61:42 2

MAC address port

-------------------------------------------

71:2B:13:45:61:41 1

64:2B:13:45:61:13 4

71:2B:13:45:61:42 2

64:2B:13:45:61:12 3

initial

A to D

D to B

B to A

C to D

31

Layer 3 Device

• Physical, data link, and network layer device

• From Mac address to IP address

• IP routing

• Router and three layer switch

32

A B C D

172.17.6.23 172.17.6.17 172.17.17.42 172.17.16.109

33

Hands On

Network Topology in our office

Hands On (1/13)

A B C D

172.17.6.23 172.17.6.17 172.17.17.42 172.17.16.109

switch

A to B

B to A

advantecher34

Hands On(2/13)

A B C D

172.17.6.23 172.17.6.17 172.17.17.42 172.17.16.109

switch

A to C

B to C

172.17.7.254

router

advantecher

advantecher

35

Hands On(3/13)

A B C D

172.17.6.23 172.17.6.17 172.17.17.42 172.17.16.109

switch

C to A

C to B

172.17.7.254172.17.17.254

router

advantecher

advantecher

36

Hands On(4/13)

A B C D

172.17.6.23 172.17.6.17 172.17.17.42 172.17.16.109

switch

A to D

B to D

172.17.7.254

router

advantecher

172.17.17.254

advantecher

37

Hands On(5/13)

A B C D

172.17.6.23 172.17.6.17 172.17.17.42 172.17.16.109

switch

172.17.7.254

routerD to A

D to B

advantecher

172.17.17.254

advantecher

38

Hands On(6/13)

A B C D

172.17.6.23 172.17.6.17 172.17.17.42 172.17.16.109

switch

172.17.7.254

routerC to D

D to B

advantecher

172.17.17.254

advantecher

39

Hands On(7/13)

A B C D

172.17.6.23 172.17.6.17 172.17.17.42 172.17.16.109

switch

172.17.7.254

router

advantecher

10.7.5.1

10.7.5.50

SQA

Z

172.17.17.254

advantecher AP router

Z to A

Z to B

40

Hands On(8/13)

A B C D

172.17.6.23 172.17.6.17 172.17.17.42 172.17.16.109

switch

172.17.7.254

router

advantecher

10.7.5.1

10.7.5.50

SQA

Z

172.17.17.254

advantecher AP router

Z to D

41

Hands On(9/13)

A B C D

172.17.6.23 172.17.6.17 172.17.17.42 172.17.16.109

switch

172.17.7.254

router

advantecher

10.7.5.1

10.7.5.50

SQA

Z

172.17.17.254

advantecher AP router

172.17.7.214

A to Zfailed

X

Firewall

42

Hands On(10/13)

A B C D

172.17.6.23 172.17.6.17 172.17.17.42 172.17.16.109

switch

172.17.7.254

router

advantecher

10.7.5.1

10.7.5.50

SQA

Z

172.17.17.254

advantecher AP router

172.17.7.214

A to tw.yahoo.com

router

43

Hands On(11/13)

A B C D

172.17.6.23 172.17.6.17 172.17.17.42 172.17.16.109

switch

172.17.7.254

router

advantecher

10.7.5.1

10.7.5.50

SQA

Z

172.17.17.254

advantecher AP router

172.17.7.214

C to tw.yahoo.com

router

44

Hands On(12/13)

A B C D

172.17.6.23 172.17.6.17 172.17.17.42 172.17.16.109

switch

172.17.7.254

router

advantecher

10.7.5.254

10.7.5.50

SQA

Z

172.17.17.254

advantecher AP router

172.17.7.214

Z to tw.yahoo.com

router

45

Hands On(13/13)

A B C D

172.17.6.23 172.17.6.17 172.17.17.42 172.17.16.109

switch

172.17.7.254

router

advantecher

10.7.5.254

10.7.5.50

SQA

Z

172.17.17.254

advantecher AP router

172.17.7.214

router

Internet

46

Thanks

47

48

IP Packet format-ToS

Bits 0-2: Precedence. Bit 3: 0 = Normal Delay, 1 = Low Delay. Bit 4: 0 = Normal Throughput, 1 = High Throughput. Bit 5: 0 = Normal Relibility, 1 = High Relibility. Bit 6-7: Reserved for Future Use.

Precedence 111 - Network Control 011 - Flash 110 - Internetwork Control 010 - Immediate 101 - CRITIC/ECP 001 - Priority 100 - Flash Override 000 - Routine