DCN286 INTRODUCTION TO DATA COMMUNICATION TECHNOLOGY

Ethernet Tech and Standards

Outdated Ethernet 10Mbps

Logical bus topologyCSMA/CD (Carrier Sense Multiple Access /

Collision Detection)Half duplex operation with hub connection

Type Cabling Max length of single cable

IEEE standard

10Base2 Thin coaxial 185m 802.3a

10Base5 Thick coaxial 500m 802.310Base-T UTP 100m 802.3i

UTP cable categoriesUTP cable category

Purpose Comments

Category 1 Telephone Not suitable for data

Category 2 Token Ring 4Mbps Token Ring

Category 3 Telephone and 10BASE-T

10Mbps

Category 4 Token Ring 16Mbps Token Ring

Category 5 Ethernet 10BASE-T and 100BASE-T

Category 5e Ethernet Same cable and connector. Support gigabit

Category 6 Ethernet Support 1Gbps. May support 10Gbps

TIA/EIA568-A and B pin outs

Pin # Function 568A wire color 568 B wire color1 TD+ White/Green White/Orange2 TD- Green Orange3 RD+ White/Orange White/Green4 Unused Blue Blue5 Unused White/Blue White/Blue6 RD- Orange Green7 Unused White/Brown White/Brown8 Unused Brown Brown

100Mbps Ethernet (Fast Ethernet)

Common Ethernet Timing Settings for 100MbpsParameter ValueBit-time 10 nano-second (nsec)Slot time 512 bit-times (5.12

microseconds)Interframe spacing 96 bitsCollision attempt limit 16Collision backoff limit 10Collision jam size 32 bitsMax untagged frame size 1518 octetsMin frame size 512 bits (64 bytes)

100BASE-TX

IEEE802.3u defines the Fast Ethernet (100Mbps) with some common features:

Can support CSMA/CD and half duplexCan disable CSMA/CD and support full

duplexSupport autonegotiationUse the same Cat5/5e cable and connector

pinoutsSame single cable length limitation (100m)Same Ethernet frame format

Trunk link

In a multiple switches environments, the link between switches is called trunk

100BASE-FX

Fast Ethernet over optical fiber using 1300nm wavelength

Was developed to overcome the limitation of 100m for 100Base-T

Not as popular as FDDI or ATM

Media Access Control (MAC)

MAC Rules and Collision Detection/Backoff

MAC Rules and Collision Detection/Backoff

Fiber Distributed Data Interface (FDDI) (optional)

Token Ring network using Token Bus timed token protocol

Can support thousands of users

Can extend range up to 200 km (124miles)

Can achieve 200Mbps with double token rings

Asynchronous Transfer Mode (ATM) (optional)

Developed by ITU (International Telecommunications Union) and ATM Forum

Packet switching protocol that encodes data into small fixed sized cells (Ethernet or IP has various length frames) @ 155Mbps

Connection oriented model to establish virtual circuit between sender and receiver

Transport real-time video and audio as well as image files, text and email over DSL lines

Packet Switching and Circuit Switching (optional)

1.The Circuit switching is to have specific circuit between nodes for exclusive use during the communication session. One example is phone conversation.

2.The Packet switching is to transmit packets in the shared network and the specific path is not required. One example is mail system. You drop the envelope into the mailbox and do not care how the post office sends the letter to the destination.

Gigabit Ethernet (1000Mbps) tech

1000BASE-T(IEEE802.3ab)

1000BASE-T (also known as IEEE 802.3ab) is a standard for gigabit Ethernet over copper wiring.

250Mbps per pair and the standard defines the way to simultaneously both send and receive over 4 pairs to achieve 1Gbps in each direction

Can support half duplex and CSMA/CD though it is not practical.

Supports up to 100m of 4-pair unshielded twisted pair

(UTP) cable with RJ45 connectors.

Common Timing Settings for 1000Mbps Ethernet

Parameter ValueBit-time 1 nano-second (nsec)Slot time 4,096 bit-times (4.096

microseconds)Interframe spacing 96 bitsCollision attempt limit 16Collision backoff limit 10Collision jam size 32 bitsMax untagged frame size 1518 octetsMin frame size 512 bits (64 bytes)

Gigabit UTP cable

The pinout is very similar to that specified in 568A/B. But, all 4 pairs would be required for bidirectional data transmitting.

1000BASE-TX

Use only 2 pairs for communication.Cat6 and 7 cables are required.Different standard to 1000BASE-T

1000BASE-X

Running over optic fiberMost popular standards are LX and SX

Standard Cable type Max. cable length

Transmitter Wavelength

1000BASE-SX

Multimode fiber

220m Laser Short, typically 850 nm

1000BASE-LX

Single mode fiber

5000m Laser Long, typically 1310 nm

1000BASE-LX (long)

Longer cover range than SXCan reach 5 -20km..

Bigger wave length than SXTypically 1310nm (1270 to 1355 nm)

1000BASE-SX (short)

Shorter cover range than LXCan reach 225 -550m.

Smaller wave length than LXTypically 850nm (770 to 860 nm)

SC connectorThe SC connector is a fiber

optic connector with a push-pull latching mechanism which provides quick insertion and removal while also ensuring a positive connection.

The SC connector has been standardized as FOCIS 3 (Fiber Optic Connector Intermateability Standards) in EIA/TIA-604-03.

MT-RJ Connector

The MTRJ connector is a small form-factor fiber optic connector which resembles the RJ-45 connector used in Ethernet networks.

The MTRJ connector was designed by AMP, but was later standardized as FOCIS 12 (Fiber Optic Connector Intermateability Standards) in EIA/TIA-604-12.

Optic fiber cable and converterTrendnet TFC-110S15 10/100Base-TX to 100Base-FX Single-Mode Fiber Converter with SC-Type Connector (15 km)Gigabit Ethernet 1000Mbps bidi media converter 10km SC connectors

This Fiber Converter with SC-Type connector transforms 1000Base-T UTP/STP media to 1000Base-LX single-modeFIB1-T1R, T1(100ohms) to fiber optic media converter, SC, single mode 15Km, SNMP

SC/SC SM Single mode fiber cable

Panel (optional)

Easy way to patch fiber cables to termination enclosures

Advantage of optic fiber

Noise immunity (optical fiber is free from EMI or RFI)

Cabling distance is greater than UTP cable to meet demand of widely range

No grounding is requiredLess electrical system requirementImmune to interception

Disadvantage of optic fiber

More challenge for cable installationMust use expensive optic fiber cable and

connectors.Need for more expensive optical transmitters and

receiversAdditional tech skills and equipment would be

required for installation, inspection and maintenance

Cannot carry electricity to operate or power terminal devices

10 Gigabit Ethernet (IEEE802.3ae)

Can run over optic fiber or UTP cable

10 giga bit per second

Various standards

Fiber (10GBASE-R)

Standard Cable type Max. cable length

Transmitter Wavelength

10GBASE-SR

Multimode fiber

26-82m Laser Short, typically 850 nm

10GBASE-LR

Single mode fiber

10-25km Laser Long, typically 1310 nm

10GBASE-T (IEEE802.3an)

Can use UTP or STP cables.10GBASE-T (IEEE802.3an) will use

Cat6 /w RJ45 connector for 55m connection.

It can reach 100m with Cat6a cable.Consume more power and has higher

latency than other 10GBASE Ethernet physical layers.

Ethernet

Ethernet is the dominant LAN tech (80-90% market share)

What makes Ethernet so popular is its reliability, lower cost, and continued enhancements in speed, security, and connection quality.

Future of the Ethernet

40 or 100 Gigabit Ethernet are in studying and working.

100Gbps, Terabit and 10Terabit would be possible in future.

Question

Any question?

If you do not have question, please search internet and collect more information of those optic fiber cables, connectors and standards.

1. Please be comfortable to draw the shape of popular connectors.

2. Please be familiar with those organizations’ full name and main responsibilities.