Transcript No Slide Title

Cisco Systems CCNA Version 3 Semester 1
Module 7
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 1
Overview
7.1 10-Mbps and 100-Mbps Ethernet
7.1.1 10-Mbps Ethernet
7.1.2 10BASE5
7.1.3 10BASE2
7.1.4 10BASE-T
7.1.5 10BASE-T wiring and architecture
7.1.6 100-Mbps Ethernet
7.1.7 100BASE-TX
7.1.8 100BASE-FX
7.1.9 Fast Ethernet architecture
7.2 Gigabit and 10-Gigabit Ethernet
7.2.1 1000-Mbps Ethernet
7.2.2 1000BASE-T
7.2.3 1000BASE-SX and LX
7.2.4 Gigabit Ethernet architecture
7.2.5 10-Gigabit Ethernet
7.2.6 10-Gigabit Ethernet architectures
7.2.7 Future of Ethernet
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 2
This module introduces the specifics of the most important varieties of
Ethernet.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 3
Students completing this module should be able to:
1.
Describe the differences and similarities among 10BASE5,
10BASE2, and 10BASE-T Ethernet.
2. Define Manchester encoding.
3. List the factors affecting Ethernet timing limits.
4. List 10BASE-T wiring parameters.
5. Describe the key characteristics and varieties of 100-Mbps
Ethernet.
6. Describe the evolution of Ethernet.
7. Explain the MAC methods, frame formats, and transmission
process of Gigabit Ethernet.
8. Describe the uses of specific media and encoding with Gigabit
Ethernet.
9. Identify the pinouts and wiring typical to the various
implementations of Gigabit Ethernet.
10. Describe the similarities and differences between Gigabit and 10
Gigabit Ethernet.
11. Describe the basic architectural considerations of Gigabit and 10
Gigabit Ethernet.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 4
Overview
7.1 10-Mbps and 100-Mbps Ethernet
7.1.1 10-Mbps Ethernet
7.1.2 10BASE5
7.1.3 10BASE2
7.1.4 10BASE-T
7.1.5 10BASE-T wiring and architecture
7.1.6 100-Mbps Ethernet
7.1.7 100BASE-TX
7.1.8 100BASE-FX
7.1.9 Fast Ethernet architecture
7.2 Gigabit and 10-Gigabit Ethernet
7.2.1 1000-Mbps Ethernet
7.2.2 1000BASE-T
7.2.3 1000BASE-SX and LX
7.2.4 Gigabit Ethernet architecture
7.2.5 10-Gigabit Ethernet
7.2.6 10-Gigabit Ethernet architectures
7.2.7 Future of Ethernet
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 5
7.1.1 10-Mbps and 100-Mbps Ethernet
All versions of Ethernet have the same:
1.
MAC addressing
2. CSMA/CD
3. Frame format
However, other aspects of the MAC sublayer, physical layer, and medium
have changed.
Legacy
Ethernet
100
802.2
Note: error ?
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 6
7.1.1 10-Mbps Ethernet
Common timing parameters – all 10 Mbps
10BASE2 - 10BASE5 - 10BASE-T
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 7
7.1.1 10-Mbps Ethernet
Common Frame Format
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 8
7.1.1 10-Mbps Ethernet
As the frame passes from the MAC sublayer to the physical layer, speed dependent
processes occur prior to the bits being placed from the physical layer onto the medium.
Differences from higher Bit Rates
??
1. Signal Quality Errors (AKA Heartbeat or CPT)
SQE is always used in half-duplex. (Can be used in full-duplex
operation but is not required.) www.ethermanage.com/ethernet/sqe/sqe.html
•
•
•
•
SQE is active:
Within 4 to 8 microseconds following a normal
transmission to indicate that the outbound frame was
successfully transmitted.
Whenever there is a collision on the medium.
Whenever there is an improper signal on the medium.
Improper signals might include jabber, or reflections that
result from a cable short.
Whenever a transmission has been interrupted.
2. 10 Mbps uses Manchester Encoding
3. 10 Mbps System Layout(Architecture features)
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 9
The purpose of the CQE signal is to test the important collision detection
electronics of the transceiver, and to let the Ethernet interface in the computer
know that the collision detection circuits and signal paths are working
correctly. The earliest Ethernet standard, DIX V1.0, did not include a test
signal for the collision detection system. However, in the DIX V2.0
specifications the transceiver was provided with a new signal called Collision
Presence Test (CPT) whose nickname was "heartbeat."
The way heartbeat works is simple: after every packet is sent, the transceiver
waits a few bit times and then sends a short burst of the collision detect signal
over the collision presence wires of the transceiver cable back to the Ethernet
interface, thereby testing all aspects of the collision detection electronics and
signal paths. The result is that the Ethernet interface in the computer receives
a heartbeat signal on the collision presence signal wires of the transceiver
cable after every packet transmission made by the interface.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 10
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 11
7.1.1 10-Mbps Ethernet
•
•
No Direct Current
Always a
synchronizing signal
Encoding – Manchester
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 12
7.1.2 10BASE5
Thick Net
•
•
•
•
•
Not recommended for new installations.
Sensitive to signal reflections on the cable.
Single point of failure.
The cable is large, heavy, and difficult to install.
Half-duplex only.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 13
7.1.2 10BASE5
1.
2.
3.
4.
Legacy Ethernet has common architectural features.
Networks usually contain multiple types of media.
The standard ensures that interoperability is maintained.
The overall architectural design is of the utmost importance
when implementing a mixed-media network.
5. It becomes easier to violate maximum delay limits as the
network grows and becomes more complex.
6. The timing limits are based on parameters such as:
• Cable length and its propagation delay
• Delay of repeaters
• Delay of transceivers
• Interframe gap shrinkage
• Delays within the station
The main advantages of 10BASE5 were:
•
It was inexpensive
•
No configuration was necessary
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 14
7.1.2 10BASE5
The 5-4-3 rule.
no more than 5 segments separated by more than 4 repeaters, and no more than three populated segments
•
•
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Not more than five segments.
No more than four repeaters may be connected in series between
any two distant stations.
No more than three populated segments.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 15
7.1.3 10BASE2
Thin Net
•
•
•
•
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Not recommended for new installations.
Sensitive to signal reflections on the cable.
Single point of failure.
Half-duplex only.
More flexible than 10BASE5 cable
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 16
7.1.3 10BASE2
Thin Net
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 17
7.1.4 10BASE-T
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 18
7.1.4 10BASE-T
Signal leaves the cable and enters the NIC on the SPLIT
Green pair. White-Green is +ve, solid Green is negative.
568B
Signal leaves the NIC and enters the cable on the Orange
pair. White-Orange is +ve, solid Orange is negative.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 19
7.1.4 10BASE-T
•
•
•
•
UTP is cheaper and easier to install
Category 3 and 5 cable are adequate for 10BASE-T networks.
New cable installations use Category 5e or better for multiple protocols.
10 Mbps of traffic in half-duplex mode and 20 Mbps in full-duplex mode.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 20
7.1.5 10BASE-T wiring and architecture
The 5-4-3 rule still applies.
•
•
•
10BASE-T links can have unrepeated distances up to 100 m.
Hubs can solve the distance issue but will allow collisions to propagate.
The 100 m distance starts over at a Switch.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 21
Overview
7.1 10-Mbps and 100-Mbps Ethernet
7.1.1 10-Mbps Ethernet
7.1.2 10BASE5
7.1.3 10BASE2
7.1.4 10BASE-T
7.1.5 10BASE-T wiring and architecture
7.1.6 100-Mbps Ethernet
7.1.7 100BASE-TX
7.1.8 100BASE-FX
7.1.9 Fast Ethernet architecture
7.2 Gigabit and 10-Gigabit Ethernet
7.2.1 1000-Mbps Ethernet
7.2.2 1000BASE-T
7.2.3 1000BASE-SX and LX
7.2.4 Gigabit Ethernet architecture
7.2.5 10-Gigabit Ethernet
7.2.6 10-Gigabit Ethernet architectures
7.2.7 Future of Ethernet
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 22
7.1 10-Mbps and 100-Mbps Ethernet
All versions of Ethernet have the same:
1.
MAC addressing
2. CSMA/CD
3. Frame format
However, other aspects of the MAC sublayer, physical layer, and medium
have changed.
100
802.2
Fast
Ethernet
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 23
7.1.6 100-Mbps Ethernet
The only difference between Ethernet
and Fast Ethernet is the Bit Time
The two technologies that have become important are 100BASE-TX, which is a
copper UTP medium and 100BASE-FX, which is a multimode optical fiber medium.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 24
7.1.6 100-Mbps Ethernet
The 100-Mbps frame format is the same as the 10-Mbps frame.
•
•
These higher frequency signals are more susceptible to noise.
In response to these issues, two separate encoding steps are used by 100Mbps Ethernet.
1.
The first part of the encoding uses a technique called 4B/5B
2. The second part of the encoding is the actual line encoding specific to
copper or fiber.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 25
1.
2.
3.
4.
5.
7.1.7 100BASE-TX/FX
The data byte to be sent is first broken into two nibbles.
If the byte is 0E, the first nibble is 0 and the second nibble is E.
Next each nibble is remapped according to the 4B5B table.
•
Hex 0 is remapped to the 4B5B code 11110.
•
Hex E is remapped to the 4B5B code 11100.
In 100BASE-FX and 100BASE-TX, the 4B5B replacement happens at
the Physical Coding Sublayer (PCS)
Information is then further encoded for transmission using
•
MLT-3 in 100BASE-TX at the Physical Medium Dependent (PMD)
sublayer
•
NRZI in 100BASE-FX at the Physical Media Attachment (PMA)
sublayer
4B5B Encoding Table
Data (Hex)
0
1
2
...
D
E
F
(Binary)
0000
0001
0010
...
1101
1110
1111
4B5B Code
11110
01001
10100
...
11011
11100
11101
There will always be
at least one ‘1’ in each
byte, eliminating long
strings of zeros.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 26
multi-level transmit-3 levels
7.1.7 100BASE-TX
100BASE-TX (like 100BASE-FX) uses 4B/5B encoding which is then
scrambled and converted to multi-level transmit-3 levels or MLT-3.
Any Transition = binary 1.
No transition = binary 0.
Long strings of zeros
would give a ‘DC’
component but because of
the 4B/5B encoding this
can never happen.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 27
7.1.7 100BASE-TX
MLT3 coding
•
•
100BASE-TX can be either full-duplex or half-duplex
An Ethernet network using separate transmit and receive wire pairs (full-duplex) and a switched
topology prevents collisions on the physical bus.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 28
7.1.7 100BASE-TX
RJ45 Pinouts are the same as 10BASE-T
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 29
Non Return to Zero, Inverted
7.1.8 100BASE-FX
Fiber cannot use the 3 level MLT3 because the
light source has only two levels, ON and OFF.
No transition = binary 0.
Any Transition = binary 1.
Long strings of zeros
would give a ‘DC’
component but because of
the 4B/5B encoding this
can never happen.
100BASE-FX (like 100BASE-TX) uses 4B/5B encoding which is then
scrambled and converted to Non Return to Zero, Inverted.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 30
7.1.8 100BASE-FX
200 Mbps transmission is possible because of the separate
Transmit and Receive paths in 100BASE-FX optical fiber.
•
•
•
The main application for which 100BASE-FX was designed was inter-building backbone connectivity
100BASE-FX was never adopted successfully. This was due to the timely introduction of Gigabit
Ethernet copper and fiber standards.
Gigabit Ethernet standards are now the dominant technology for backbone installations, high-speed
cross-connects, and general infrastructure needs.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 31
7.1.8 100BASE-FX
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 32
7.1.8 100BASE-FX
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 33
7.1.8 100BASE-FX
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 34
7.1.8 100BASE-FX
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 35
7.1.8 100BASE-FX
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 36
7.1.9 Fast Ethernet architecture
A Class I repeater may introduce up to 140 bit-times of
latency. Any repeater that changes between one Ethernet
implementation and another is a Class I repeater.
A Class II repeater may only introduce
a maximum of 92 bit-times latency.
1.
2.
3.
The introduction of switches has made this distance limitation less important.
If workstations are located within 100 m of a switch, the 100 m distance starts over at
the switch.
Since most Fast Ethernet is switched, these are the practical limits between devices.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 37
7.1.9 Fast Ethernet architecture
1. Only one Class I repeater can be used in a single
collision domain.
2. Two Class II repeaters are allowed in a single collision
domain, with up to a 5 meter inter-repeater link
between them.
3. Class II repeaters are faster than Class I repeaters.
4. This allows Class I repeaters to provide other services
besides simple repeating, such as translating between
100BASE-TX and 100BASE-T4.
5. Class II repeaters are primarily used to link two hubs
each supporting only a single implementation of Fast
Ethernet.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 38
Overview
7.1 10-Mbps and 100-Mbps Ethernet
7.1.1 10-Mbps Ethernet
7.1.2 10BASE5
7.1.3 10BASE2
7.1.4 10BASE-T
7.1.5 10BASE-T wiring and architecture
7.1.6 100-Mbps Ethernet
7.1.7 100BASE-TX
7.1.8 100BASE-FX
7.1.9 Fast Ethernet architecture
7.2 Gigabit and 10-Gigabit Ethernet
7.2.1 1000-Mbps Ethernet
7.2.2 1000BASE-T
7.2.3 1000BASE-SX and LX
7.2.4 Gigabit Ethernet architecture
7.2.5 10-Gigabit Ethernet
7.2.6 10-Gigabit Ethernet architectures
7.2.7 Future of Ethernet
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 39
7.2.1 1000-Mbps Ethernet
All versions of Ethernet have the same:
1.
MAC addressing
2. CSMA/CD
3. Frame format
However, other aspects of the MAC sublayer, physical layer, and medium
have changed.
100
802.2
Gigabit
Ethernet
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 40
7.2.1 1000-Mbps Ethernet
Gigabit
Ethernet
Fast
Ethernet
1000BASE-T inter-switch links are useful for
•
video streaming applications
•
server to DAT backup drive links
•
intra-building backbones
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 41
Once again the frame remains unchanged.
To interconnect a 1000BASE-T network to a 100BASE-T network use a layer 2 bridge or switch.
The differences between standard Ethernet, Fast Ethernet and Gigabit Ethernet
occur at the physical layer.
•
•
•
•
•
•
Since the bits are introduced on the medium for a shorter duration and more
often, timing is critical.
This high-speed transmission requires frequencies closer to copper medium
bandwidth limitations.
This causes the bits to be more susceptible to noise on copper media.
Like 100Base-TX these issues require Gigabit Ethernet to use two separate
encoding steps.
Data transmission is made more efficient by using codes to represent the
binary bit stream.
The encoded data provides synchronization, efficient usage of bandwidth,
and improved Signal-to-Noise Ratio characteristics.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 42
Because Gigabit Ethernet is inherently full-duplex, the Media
Access Control method views it as a point-to-point link.
•
•
•
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•
•
Cat 5e cable can reliably carry up to
125 Mbps of traffic.
1000BASE-T uses all four pairs of
wires.
This is done using complex circuitry
called a Hybrid to allow full duplex
transmissions on the same wire pair.
This provides 250 Mbps per pair.
With all four-wire pairs, this provides
the desired 1000 Mbps.
Since the information travels
simultaneously across the four paths,
the circuitry has to divide frames at
the transmitter and reassemble them at
the receiver.
1st Frame
2nd Frame
3rd Frame
4th Frame
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 43
•
•
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•
•
•
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For 1000BASE-T 4D-PAM5
line encoding is used on Cat
5e or better UTP.
The actual transmitted
signal in each direction on
each wire pair is a 5-level
{+2, +1, 0, -1, -2} pulse
modulated symbol (PAM5).
This results in a permanent
collision on the wire pairs.
These collisions result in
complex voltage patterns.
With the complex integrated circuits using techniques such as echo cancellation, Layer 1
Forward Error Correction (FEC), and prudent selection of voltage levels, the system achieves
the 1 Gigabit throughput.
In idle periods there are nine voltage levels found on the cable, and during data transmission
periods there are 17 voltage levels found on the cable.
With this large number of states and the effects of noise, the signal on the wire looks more
analog than digital.
Like analog, the system is more susceptible to noise due to cable and termination problems.
The use of full-duplex 1000BASE-T is widespread.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 44
Why is the half-duplex operation undesirable for Gigabit Ethernet? (Choose three.)
1.
Gigabit Ethernet is inherently full-duplex.
2.
Half-duplex operation reduces the effective cable lengths.
3.
Half-duplex operation introduces increased overhead by the carrier extension.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 45
•
•
•
Fiber cannot do multi level signaling (not 4D-PAM5 nor MLT3)
at 1 Gigabit Non Return to Zero (NRZ) signaling is used with
8B/10B coding to ensure that a good synchronizing signal is always
present.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 46
Features And Operation Of 8B/10B Encoding
Every ten bit code group must fit into one of the
following three possibilities:
1.
2.
3.
Six ones and four zeros
Five ones and five zeros
Four ones and six zeros
This helps limit the number of consecutive ones and zeros
between any two code groups.
Examples of 8B/10B coding
Code
Group
Name
Actual Byte
Being
Encoded
RDEncoding
Value
RD+
Encoding
Value
Effect on
RD after
Sending
D1.0
000 00001
011101 0100
100010 1011
same
D4.1
001 00100
110101 1001
001010 1001
flip
D28.5
101 11100
001110 1010
001110 1010
same
D28.5
101 11100
001111 1010
110000 0101
flip
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 47
Any Transition = binary 1
No transition = binary 0
NRZI
Light = binary 1
No Light = binary 0
NRZ
1
0
1
0
0
1
0
1
1
1
1000BASE-S or L X
8B/10B
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 48
Different sub layers in the Physical Layer
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 49
L=Long Wave
Length 1300nm
5000
550
S=Short Wave
Length 850 nm
550
error
multimode
550
275
•
100
25
•
•
The Media Access Control method
treats the link as point-to-point.
Since separate fibers are used for
transmitting (Tx) and receiving (Rx) the
connection is inherently full duplex.
Gigabit Ethernet permits only a single
repeater between two stations.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 50
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 51
error
Single mode
The bandwidth of fiber is inherently very large. It has been limited by
•
emitter technology
•
fiber manufacturing processes
•
detector technology
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 52
Table 1 100BASE-TX, 1000BASE-X, and 1000BASE-T
100BASE-TX
1000BASE-X
1000BASE-T
Frame format
802.3 Ethernet
802.3 Ethernet
802.3 Ethernet
MAC protocol
802.3 Ethernet
802.3 Ethernet
802.3 Ethernet
Flow control
802.3x
802.3x
802.3x
Symbol rate
125 Mbaud
125 Mbaud
1.25 Gbaud
Data rate
100 Mbps
1000 Mbps
1000 Mbps
Encoding (PCS)
ANSI FDDI 4B/5B
ANSI FC 8B/10B
5 level PAM
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 53
Overview
7.1 10-Mbps and 100-Mbps Ethernet
7.1.1 10-Mbps Ethernet
7.1.2 10BASE5
7.1.3 10BASE2
7.1.4 10BASE-T
7.1.5 10BASE-T wiring and architecture
7.1.6 100-Mbps Ethernet
7.1.7 100BASE-TX
7.1.8 100BASE-FX
7.1.9 Fast Ethernet architecture
7.2 Gigabit and 10-Gigabit Ethernet
7.2.1 1000-Mbps Ethernet
7.2.2 1000BASE-T
7.2.3 1000BASE-SX and LX
7.2.4 Gigabit Ethernet architecture
7.2.5 10-Gigabit Ethernet
7.2.6 10-Gigabit Ethernet architectures
7.2.7 Future of Ethernet
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 54
7.2.5 10-Gigabit Ethernet
All versions of Ethernet have the same:
1.
MAC addressing
2. CSMA/CD
3. Frame format
However, other aspects of the MAC sublayer, physical layer, and medium
have changed.
100
802.2
10 Gigabit Ethernet
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 55
Gigabit
Ethernet
Fast
Ethernet
All versions of Gigabit Ethernet have the same frame format, timing and transmission
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 56
How does 10GbE compare to other varieties of Ethernet?
1.
2.
3.
4.
5.
6.
Frame format is the same, allowing interoperability between all
varieties of legacy, fast, gigabit, and 10 Gigabit, with no
reframing or protocol conversions.
Bit time is now 0.1 nanoseconds. All other time variables scale
accordingly.
Since only full-duplex fiber connections are used, CSMA/CD is
not necessary
The IEEE 802.3 sublayers within OSI Layers 1 and 2 are mostly
preserved, with a few additions to accommodate 40 km fiber
links and interoperability with SONET/SDH technologies.
Flexible, efficient, reliable, relatively low cost end-to-end
Ethernet networks become possible.
TCP/IP can run over LANs, MANs, and WANs with one Layer 2
Transport method.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 57
802.3ae June 2002 10GbE family.
1. 10GBASE-SR – Intended for short distances over alreadyinstalled multimode fiber, supports a range between 26 m to 82
m
2. 10GBASE-LX4 – Uses wavelength division multiplexing (WDM),
supports 240 m to 300 m over already-installed multimode fiber
and 10 km over single-mode fiber
3. 10GBASE-LR and 10GBASE-ER – Support 10 km and 40 km
over single-mode fiber
4. 10GBASE-SW, 10GBASE-LW, and 10GBASE-EW – Known
collectively as 10GBASE-W are intended to work with OC-192
synchronous transport module (STM) SONET/SDH WAN
equipment.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 58
10GBASE-LX4 uses Wide Wavelength Division Multiplex (WWDM) to multiplex four bit
simultaneous bit streams as four wavelengths of light launched into the fiber at one time.
Physical Media
Attachment
Physical Media
Dependent
Each transceiver has four 3.125-Gbit/s
DFB lasers that are optically multiplexed
to provide a 10-Gbit/s data throughput.
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 59
http://standards.ieee.org/getieee802/802.3.html
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 60
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 61
Coarse Wavelength Division Multiplexing
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 62
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 63
Overview
7.1 10-Mbps and 100-Mbps Ethernet
7.1.1 10-Mbps Ethernet
7.1.2 10BASE5
7.1.3 10BASE2
7.1.4 10BASE-T
7.1.5 10BASE-T wiring and architecture
7.1.6 100-Mbps Ethernet
7.1.7 100BASE-TX
7.1.8 100BASE-FX
7.1.9 Fast Ethernet architecture
7.2 Gigabit and 10-Gigabit Ethernet
7.2.1 1000-Mbps Ethernet
7.2.2 1000BASE-T
7.2.3 1000BASE-SX and LX
7.2.4 Gigabit Ethernet architecture
7.2.5 10-Gigabit Ethernet
7.2.6 10-Gigabit Ethernet architectures
7.2.7 Future of Ethernet
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 64
7.2.7 Future of Ethernet
1.
2.
3.
Copper (up to 1000 Mbps, perhaps more)
Wireless (approaching 100 Mbps, perhaps more)
Optical fiber (currently at 10,000 Mbps and soon to be more)
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 65
FIN
Oct-03 ©Cisco Systems CCNA Semester 1 Version 3 Comp11 Mod7 – St. Lawrence College – Cornwall Campus, ON, Canada – Clark slide 66