DCN286 INTRODUCTION TO DATA
COMMUNICATION TECHNOLOGY
Ethernet Tech and Standards
Outdated Ethernet 10Mbps
Type
Cabling
Thin coaxial
Max length of
single cable
185m
IEEE
standard
802.3a
10Base2
10Base5
10Base-T
Thick coaxial
UTP
500m
100m
802.3
802.3i
 Logical bus topology
 CSMA/CD (Carrier Sense Multiple Access /
Collision Detection)
 Half duplex operation with hub connection
UTP cable categories
UTP cable
category
Category 1
Purpose
Comments
Telephone
Not suitable for data
Category 2
Token Ring
4Mbps Token Ring
Category 3
10Mbps
Category 4
Telephone and
10BASE-T
Token Ring
Category 5
Ethernet
Category 5e
Ethernet
10BASE-T and 100BASET
Same cable and
connector. Support gigabit
Category 6
Ethernet
16Mbps Token Ring
Support 1Gbps. May
support 10Gbps
TIA/EIA568-A and B pin outs
Pin #
1
2
3
4
5
6
7
8
Function
TD+
TDRD+
Unused
Unused
RDUnused
Unused
568A wire color
White/Green
Green
White/Orange
Blue
White/Blue
Orange
White/Brown
Brown
568 B wire color
White/Orange
Orange
White/Green
Blue
White/Blue
Green
White/Brown
Brown
100Mbps Ethernet (Fast Ethernet)
Common Ethernet Timing Settings for 100Mbps
Parameter
Value
Bit-time
10 nano-second (nsec)
Slot time
512 bit-times (5.12
microseconds)
Interframe spacing
96 bits
Collision attempt limit
16
Collision backoff limit
10
Collision jam size
32 bits
Max untagged frame size
1518 octets
Min 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 duplex
Can disable CSMA/CD and support full
duplex
Support autonegotiation
Use the same Cat5/5e cable and connector
pinouts
Same 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
Bit-time
Slot time
Value
1 nano-second (nsec)
4,096 bit-times (4.096
microseconds)
Interframe spacing
96 bits
Collision attempt limit
16
Collision backoff limit
10
Collision jam size
32 bits
Max untagged frame size 1518 octets
Min 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 fiber
 Most popular standards are LX and SX
Standard
Cable type Max.
cable
length
Transmitter Wavelength
1000BASE Multimode 220m
-SX
fiber
Laser
Short, typically
850 nm
1000BASE Single
5000m
-LX
mode fiber
Laser
Long, typically
1310 nm
1000BASE-LX (long)
Longer cover range than SX
Can reach 5 -20km..
Bigger wave length than SX
Typically 1310nm (1270 to 1355 nm)
1000BASE-SX (short)
Shorter cover range than LX
Can reach 225 -550m.
Smaller wave length than LX
Typically 850nm (770 to 860 nm)
SC connector
 The SC connector is a fiber
optic connector with a pushpull 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 converter
Trendnet TFC-110S15 10/100Base-TX to 100BaseFX 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-mode
FIB1-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 required
Less electrical system requirement
Immune to interception
Disadvantage of optic fiber
 More challenge for cable installation
 Must use expensive optic fiber cable and
connectors.
 Need for more expensive optical transmitters and
receivers
 Additional 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 Transmitter Wavelength
length
10GBASESR
10GBASELR
Multimode 26-82m
fiber
Single
10-25km
mode fiber
Laser
Laser
Short, typically
850 nm
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 (8090% 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.