1 smu course #: ee 8301 ntu course #: st 750-n data communications session #28 -- dr. baker december...
TRANSCRIPT
1
SMU Course #: EE 8301NTU Course #: ST 750-N
DATA COMMUNICATIONSSession #28 -- Dr. Baker
December 3, 1998
“Live” Class Call-In Line: (214)768-3068Tape Problems: [email protected]
2
www.caida.ord
3
Dennis Heimann
District Sales Manager
AMP Incorporated
4
The Cabling Apple Cart Turns Over
Tony Beam, RCDDDirector of Global Systems Marketing
Presented By:
Dennis Heimann, RCDD
District Sales Manager
5
Gigabit Data Rates Market Trends/Drivers
• Demands on LANs are increasing Users desire latest technology Increasingly complex applications require more memory PC processing power doubling every 1.5 - 2 years Client/server computing increased to share applications End result is network stress
• Cabling should be part of the solution,
not part of the problem!
6
Cabling, LAN Technologies & StandardsChicken & Egg Story
LAN Technologies• 622 Mbps ATM• Gigabit Ethernet
LAN Standards• ATM Forum• IEEE 802.3
Cabling Trends• Power Sum • E-DIN 44312-5 Category 6• Levels Program
Cabling Standards• Enhanced Cat 5• Cat 6/Class E• Cat 7/Class F
7
LAN Technologies Data Rate and Signal Bandwidth
Network CablePairs
FullDuplex
LineCode
Min. SignalBandwidth
CodingLevels
CablingCategory
10 Base-T 2 No Manch-ester
10 MHz 2 3
100VG-AnyLAN
4 No NRZ 12.5 MHz 2 3
100 Base-Tx 2 No MLT-3 32.5 MHz 3 5
155 Mb/sATM
2 Yes NRZ 77.5 MHz 2 5
1000 Base-T 4 Yes TX/T2 62.5 MHz 5 5?
8
Gigabit Ethernet Copper Physical Layer Interfaces
Media Access Control (MAC)full duplex and/or half duplex
1000BASE-X 8B/10Bencoding/ decoding
Gigabit Media Independent Interface
1000BASE-TCat 5 UTPXcvr
1000BASE-T Copper PHYencoder/decoder
100m
802.3z physical layer802.3z physical layer802.3ab802.3abphysical layerphysical layer
with DSPwith DSP
1000BASE-CXShielded Balanced Copper Xcvr
25m
9
Gigabit Ethernet On Copper Physical Layer
• Objective is for eventual GE deployment to desktop on existing Category 5 cabling (US penetration 72%)
• Simultaneously transmit and receive at 250Mb/s on all four pairs.
• 5-Level PAM (Pulse Amplitude Modulation) and pulse shaping so spectrum is same as 100BASE-TX
• Requires higher SNR (signal to noise) for given BER than 100BASE-TX because of multi-level signaling
• Digital Signal Processing (DSP) is used to cancel some of the noise
• Due to DSP a 1000BASE-T Xcvr may have the complexity of a 486 processor and initially cost 5 times more than a 100BASE-TX Xcvr
10
CablingEvolving Horizontal Cabling Platforms
20001996199219881984
1000
100
10
1
1000
100
10
1
155 Mb/s ATM
100BASE-Tx
10BASE-T16 Mb/s Token Ring
4 Mb/sToken Ring
CAT4CAT4 CAT5CAT5CAT3CAT3
Mb/sMHzData RateBandwidth
1000BASE-T
1.2 Gbps ATM ?
?
CAT XCAT X
11
CablingThe Performance Decision
Cat 5/Class DMargin
Level 6
Level 7
Level 5EnhancedEnhanced Cat 5+
Cat 6/Class E
Cat 7/Class F
Headroom!
Characte
rized
to 350 M
Hz
Able to transmit 622 Mbps
to the workstation
able
to transm
it 1000 M
bps
to the w
orkstatio
nSingle-mode
50 µm
62.5 µm
Aggregate Bandwidth
Filtering through the Premises Cabling Revolution.
12
• Original industry performance spec for CAT 5 TIA/EIA-568-A, Category 5 ISO/IEC 11801, Class D CENELEC EN 50173, Class D AS/NZS 3080: 1996, Class D
• Specifies requirements for pair-to-pair performance
• Considered “Bare Bones” technology
• Recently amended to include Skew addendum
Current Industry Definition Category 5/Class D
13
Performance CharacteristicsPair-to-Pair Systems (Review)
• Key Performance Parameters Near End Crosstalk (NEXT) Attenuation Attenuation to Crosstalk Ratio (ACR)
Pair 1
Pair 2
NIC HUB
XC
VR
XC
VR
14
Performance Characteristics Attenuation to Crosstalk (Loss) Ratio
Transmitter Receiver
Receiver Transmitter
Transmitted Signal
Attenuated Signal
Coupled NEXT Noise
ACRAttenuated Signal NEXT Noise
NIC HUB
15
Channel ACR Minimum for Cat 5
0
5
10
15
20
25
30
35
40
45
0 20 40 60 80 100
Frequency MHz
dB
NEXT Limit
Attenuation Limit
Minimum ACR3.1
16
But Wait, There’s More
• SP-4194 Proposed TSB to 568-A Additional Transmission
Performance Specifications for 100 Ohm 4-Pair Category 5 Cabling
Informative not required
• SP-4195 Proposed Addendum No. 5
to 568-A Additional Transmission
Performance Specifications for 4-Pair 100 Ohm Enhanced Category 5 Cabling
Requirements
TIA has two draft addenda out for ballot now -
17
SP-4194 - Additional Cat 5 Specifications
“The development of certain high-speed applications has brought to the attention of the TIA the need for additional transmission requirements such as return loss and far end crosstalk (FEXT). These parameters are needed by system designers for applications that utilize all four pairs in the cable for full duplex transmission.”
“Although these are new specifications, the existing worst-case, two-connector topologies compliant with TIA/EIA-568-A are expected to meet these requirements. Other topologies are supported as long as they meet the ELFEXT and Return Loss requirements of this document.”
18
Two-connector Topologies?
Other Topologies. . .(i.e. with cross-connect and/or transition point)
19
SP-4195 - Enhanced Cat 5
“The development of certain high-speed applications has brought to the attention of the TIA the need for additional transmission requirements such as multi-disturber NEXT, return loss and multi-disturber far end crosstalk (FEXT). These parameters are needed by system designers for applications that utilize all four pairs in the cable for simultaneous bi-directional transmission.”
“Addendum 5 for category 5e cabling provides higher performance over a minimally compliant category 5 channel and recognizes advances in cabling technology.”
20
So What Do the Giga-guys Say?
IEEE Draft P802.3ab/D2.0
Physical layer specification for 1000 Mb/s operationon four pairs of Category 5 or better balanced twistedpair cable (1000BASE-T)
40.8 Link Segment Characteristics1000BASE-T uses a duplex transmission system. Four full duplex channels are required to transport data between two PMDs. Each duplex channel supports an effective data rate of 250 Mbps in each direction simultaneously. The term ‘link segment’ used in this clause refers to four duplex channels and the term ‘duplex channel’ will be used to refer a single channel with full duplex capability. Specifications for a link segment applies equally to each for the four duplex channels.
1000BASE-T is designed to operate over a 4-pair Category 5 cabling system.
21
Designed to Operate Over Cat 5, BUT. . .
ANNEX 40A Additional Cabling Design Guidelines
Although the 1 Gb/s specification described in Clause 40 was designed to operate over 4-pair Category 5 cabling systems as specified in ANSI/TIA/EIA-568-A and ISO/IEC 11801, there are additional steps that may be taken by network designers that will provide additional operating margins and ensure the objective BER of 10-10 is achieved.
•Power Sum NEXT•Defined but not spec’d higher than Cat 5
•Power Sum ELFEXT•Spec’d in Addendum 4 (Cat 5)
•Don’t use 25-pair•Don’t use crossconnect or transition point
22
Performance Specifications4 Pair Systems
• Additional Performance Parameters Power Sum NEXT Power Sum ELFEXT Return Loss Skew
Pair 1
Pair 2
Pair 3
Pair 4
100or
1000Mb/s
100or 1000Mb/s
NIC HUB
23
• EMI - Non-cancelable by DSP
4 Pair Systems1000BASE-T Noise Sources
NIC HUB
1000Mb/s
1000Mb/s
EMI
Return Loss
PS FEXTPS NEXT
250 Mb/s Full Duplex
• NEXT - Cancelable by DSP• NEXT - Cancelable by DSP
• Return Loss
• FEXT - Non-Cancelable by DSP
24
Cabling StandardsANSI/TIA/EIA-568-A Draft Addendums
• ELFEXT
• Return Loss
• PS NEXT
• Return Loss
• ELFEXT
Additional Transmission Performance Specifications for 100 Ohm 4-Pair Category 5 Cabling
Minimum recommendation for new installations
Additional Transmission Performance Specifications for 100 Ohm 4-Pair Enhanced Category 5 Cabling
Informative not requirements
25
CHANNEL (dB) LINK (dB)100 Mhz 100 Mhz
Attenuation 24 21.6P-P NEXT 30 32PS NEXT 27 29.3ELFEXT 19 21
PS ELFEXT 16 18ACR 6** 10.4**
PS ACR 3** 7.7**RETURN LOSS 10.1 12.1
Current Industry Definition Enhanced Category 5
Link and Channel Performance Specifications*
*Draft figures only and subject to change**Values are calculated and not a requirement of the Standard
26
Current Industry DefinitionCategory 6/Class E
• Industry Specification: Originally a European de facto standard to be fully compliant with EN
50173 and show a positive ACR at 300 MHz Recently proposed by ISO/IEC 11801-A as Category 6/ Class E
specifying positive channel performance to 200 MHz.
• Purpose ISO released these channel performance specifications to IEEE and the
ATM forum to assist them in new network equipment development Necessary to future proof premises cabling systems that will utilize high
bandwidth leading edge applications over the life of the cabling system. Allows customer a choice of high performance unshielded or shielded
cabling
27
CC CHANNEL (dB) IC CHANNEL (dB) LINK (dB)100 Mhz 200 Mhz 100 Mhz 200 Mhz 100 Mhz 200 Mhz
Attenuation 21.6 31.8 21.6 31.8 18.6 27.3P-P NEXT 39.9 34.8 41.8 36.9 41.8 36.9PS NEXT 37.1 31.9 39.3 34.3 39.3 34.3ELFEXT 23.2 17.2 25.2 19.2 25.2 19.2
PS ELFEXT 20.2 14.2 22.2 16.2 22.2 16.2ACR 18.3 3.0 20.2 5.1 23.2 9.6
PS ACR 15.4 0.0 17.7 2.5 20.7 7.0RETURN LOSS 12.0 9.0 12.0 9.0 14.1 12.0
Current Industry Definition Category 6/Class E
Link and Channel Performance Specifications*
*Draft figures only and subject to change
28
ACR for Category 5 , 5+ , 6 Channel
Cat 6Cat 5 Cat 5+Cat 5+
0 50 100 150 200
Frequency MHz
0
10
20
30
40
50
60
70
80dB
NEXT Loss
Attenuation
Cat 5 ACR 3.1dB min..
Cat 5+ ACR 6 dB min. (prop.)Cat 5+ ACR 6 dB min. (prop.)
Cat 6 ACR 18.3 db min. (prop.)
29
Cat 6
Enhanced
Cat 5
Materials and Labor*Installed Cost
127%
100%
92%
* Estimated labor by BICSI
08
UTP System Installed Channel Cost Comparison
30
Current Industry DefinitionCategory 7/Class F
• Industry Specification: Originally defined by E DIN 44312-5, Class E (Germany’s effort to
establish a next generation Copper performance category) Recently proposed for ISO/IEC 11801-A Category 7/Class F
specifying positive system channel performance to 600 MHz. IEEE has suggested characterization up to 750 MHz.
• Purpose Originally designed to support 622 Mbps ATM on two pairs using
simple NRZ encoding A shielded cabling solution that future proofs premises cabling
systems and assures sheath sharing capabilities for the higher speed applications.
31
Shielded Cable Types
FTP = Overall foil shield S-FTP = Overall foil shield plus an additional braid 100CAT3/4/5/6 Shield used to improve EMC performance
STP or STP-A = 150 IBM Cabling System PiMF = 100“Pairs in Metal Foil” cables Individual pairs shielded to improve NEXT performance Overall shield used to improve EMC performance
STP or PiMF
FTP or S-FTP
32
Backbone Requirements Effects of Evolving Networking Traffic Flow
• Centralized server farms vs. departmental servers
• Centralized control of data vs. hard drive Databases Images Presentations and documents Intranet, Extranet and Internet
• Evolving network PCs
• Old rule - 80% local, 20% backbone traffic
• New rule - 20% local, 80% backbone traffic
• Shared to switched - now backbone can be the bottleneck
33
Cabling Evolving Backbone Cabling Platforms
20001997199419881984
SM
500
160
10,000
1,000
100
10
Mb/sMHz•kmData RateBandwidth
1986
FDDI155ATMFastEthernet
LW
622 ATM
SWLW
1000 Base-F1.2 Gbps ATM
SW
10BASE-F
SW?
??
2.5 Gbps ATM
34
Gigabit Ethernet Optical Fibre Physical Layer Interfaces
Media Access Control (MAC)full duplex and/or half duplex
1000BASE-X 8B/10Bencoding/ decoding
1000BASE-LX LWLXcvr
1000BASE-SXSWLXcvr
Gigabit Media Independent Interface
1000BASE-T Copper PHYencoder/decoder
SMF-5km50um-550m
62.5um-550m
50um-550m62.5um-220m
802.3z physical layer802.3z physical layer802.3ab802.3abphysical layerphysical layer
35
What Has ChangedSince 62.5 micron was Standardized?
• Data rate requirements exceeds capabilities of LEDs
• Numerical aperture no longer critical LED output power and align improves Connector alignment and polishing improves
• Shortwavelength VSCELs are introduced and are the future for high-speed applications Fibre Channel 622 Mbps ATM 1 Gbps Ethernet/1.2 Gbps ATM
• SM Lasers and connector still not cost-competitive Gigabit VSCEL 1/3rd the price of LW laser Should equate to $1000 plus premium to the customer
36
The “Facts”On Next-Generation Optical Fiber Systems
• Combining laser sources with multimode fiber is a relatively new concept in the LAN market.
• The installed base of fiber is optimized for use with LEDs
• Most combinations of laser sources and multimode fiber produce superior performance.
• Some combinations of multimode fiber and laser sources produce poorer than expected performance.
• Examples of poor performance have been verified with 62.5um fiber and single mode lasers.
• No examples of poor performance of 50 um fiber have been found.
• 50um fiber cable typically 10 to 15% less expensive.
37
Status of StandardsNow is the time to move forward and make a change
• Gigabit Ethernet:
• TR-41.8 (TIA 568 Cabling Standard): 50 um fiber recommend by FOTG for inclusion in next revision of TIA-568 AMP expects adoption with next revision
• JTC1SC25WG3 (ISO/IEC 11801 Cabling Standard): 50 um fiber included in standard
• 50um fiber specifications exists to insure interoperability
ShortWavelenght
LongWavelenght
62.5 µm 220 550
50 µm 550 550Single-mode ---- 5,000
38
50 µm CableSupport for Existing Standards
• Maximum power penalty with LEDs - 4.6dB
• Long Wavelength LED Applications FDDI, Fast Ethernet, and 155 Mbps ATM Power budget supports full 2 km distance
• Short Wavelength LED Applications 10Mbps Ethernet and 4/16 Mbps TR Specifications do not support full 2 km distance However three leading suppliers of transceivers exceed
power specifications Testing indicates support for 2 km distance
Uses the same electronics and connectors
39
Optical BackbonesDistributed Network Architecture
TC
Equipment Room
Server
Max 90 mM
ax 5
00 m
(fi
bre
)
TC
TC = Telecommunications Closet
40
Intra-building Optical Backbones Sizing for Performance
Backbone Requirements in Mbps
Use
r R
equ
irem
ents
in M
bp
s
Based on 100 Users/closetand 500m cable length
Shared100
FDDI100BaseF155 ATM
Shared 101, 2 or 5 Segments
Switched 10
1000BaseF1.2Gbps ATM
Switched100
2.5 Gbps ATM
0
0.1
0.2
0.5
1.0
10.0
1000.0
0
100.0
10 100 1000 10,000 100,000
Switched1000
Next Gen Apps.
62.5/125
50/125 Parallel 50 Links
Single mode
Bandwidth growth
41
Optical Cabling Centralized Network Architecture
Equipment Room
Server
Interconnect or splice
Max 300 m total (fibre)TC?
TC = Telecommunications Closet
Pull Through
42
CNA Optical Cabling Sizing for Performance
CNA Data Rate in Mbps
Use
r D
ata
Rat
e in
Mb
ps
10.0
1000.0
100.0
1.0 10 100 1,000
Bandwidth growth
Independent of # of usersBased on 300 meters cable length
Switched 10
Switched10Base F
Switched1000
Switched1000BaseF
50/125
Switched100Base F
Switched100Base F
0.5
0
0.1
0.2
0.5
1.0
0
Shared100
Shared 10Base F
Shared 101, 2 or 5 Segments
62.5/125
43
Next-Generation Optical Connectors (Jacks)
ST 568SC
Small-Form Factor
MT-RJLC
VF
44
The Next Standard 2-Fiber System
To Hub
On board
Commercially Available Fiber
Cable
Commercially Available Fiber Cable
45
MT-RJ Plug / JackMT-RJ Plug / Jack
568SC568SC
• Duplex Plug-Adapter-Plug Interface.
• Specialized cut-outs
• Depth to cable transition = 1.95”
• Surface Mounted interface
Size Does Matter!
• Drop-In replacement for existing
8-position modular connectors
• Depth to cable transition = .926”
• Fits INTO J-Box
46
Small Form Factor ConnectorsSolves the Electronics Issue
47
Issues to be Considered in Selection Process
• Intermateability Specifications (TIA FOCIS)
• Meet or exceed draft TIA connector performance specifications
• Strength of true supporters Connector manufacturers Transciever manufacturers LAN Electronic manufacturers
• Innovation balanced by realiability
• Ease of termination - labor cost reduction
48
Intra-building Backbone -Typically 62.5/125multimode fiber but50/125 fiber isrecommended forgreater bandwidth
Horizontal Cabling -Typically Category 5but quickly changing toEnhanced Category 5as minimum requirement
CONCLUSIONCabling Sub-System Trends
Inter-building Backbone -Typically multimode fiberbut should include somesingle mode fiber for longer distances
49
Thank you
50
E-Mail Address: [email protected] Problems: [email protected]
End of Session #28
EE 8301 ST750-NDr. Baker