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SMU Course #: EE 8301 NTU Course #: ST 750-N. “Live” Class Call-In Line: (214)768-3068 Tape Problems: vthelp@seas.smu.edu. DATA COMMUNICATIONS. Session #28 -- Dr. Baker. December 3, 1998. www.caida.ord. Dennis Heimann District Sales Manager AMP Incorporated.
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SMU Course #: EE 8301NTU Course #: ST 750-N “Live” Class Call-In Line: (214)768-3068 Tape Problems: vthelp@seas.smu.edu DATA COMMUNICATIONS Session #28 -- Dr. Baker December 3, 1998
Dennis Heimann District Sales Manager AMP Incorporated
The Cabling Apple Cart Turns Over Presented By: Dennis Heimann, RCDD District Sales Manager Tony Beam, RCDD Director of Global Systems Marketing
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!
LAN • Standards • ATM Forum • IEEE 802.3 • Cabling Trends • Power Sum • E-DIN 44312-5 Category 6 • Levels Program • LAN • Technologies • 622 Mbps ATM • Gigabit Ethernet • Cabling • Standards • Enhanced Cat 5 • Cat 6/Class E • Cat 7/Class F Cabling, LAN Technologies & Standards Chicken & Egg Story
Gigabit Ethernet Copper Physical Layer Interfaces Media Access Control (MAC) full duplex and/or half duplex Gigabit Media Independent Interface 1000BASE-T Copper PHY encoder/decoder 1000BASE-X 8B/10B encoding/ decoding 1000BASE-CX Shielded Balanced Copper Xcvr 1000BASE-T Cat 5 UTP Xcvr with DSP 25m 100m 802.3ab physical layer 802.3z physical layer
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
1.2 Gbps ATM ? 1000BASE-T 1000 100 ? 10 CAT X 1 CablingEvolving Horizontal Cabling Platforms Bandwidth Data Rate MHz Mb/s 1000 155 Mb/s ATM 100 100BASE-Tx 16 Mb/s Token Ring 10BASE-T 10 4 Mb/s Token Ring CAT3 CAT4 CAT5 1 1984 1988 1992 1996 2000
Margin Level 5 Cat 5+ Enhanced 62.5 µm Level 6 Cat 6/Class E 50 µm Level 7 Cat 7/Class F Single- mode Headroom! CablingThe Performance Decision Cat 5/Class D Characterized to 350 MHz Filtering through the Premises Cabling Revolution. Able to transmit 622 Mbps to the workstation able to transmit 1000 Mbps to the workstation Aggregate Bandwidth
Current Industry Definition Category 5/Class D • 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
Pair 1 XCVR XCVR Pair 2 NIC HUB Performance CharacteristicsPair-to-Pair Systems (Review) • Key Performance Parameters • Near End Crosstalk (NEXT) • Attenuation • Attenuation to Crosstalk Ratio (ACR)
Performance Characteristics Attenuation to Crosstalk (Loss) Ratio NIC HUB Coupled NEXT Noise Receiver Transmitter Receiver Transmitter Attenuated Signal Transmitted Signal ACR Attenuated Signal NEXT Noise
Channel ACR Minimum for Cat 5 45 40 NEXT Limit 35 30 3.1 25 Minimum ACR 20 dB 15 10 Attenuation Limit 5 0 0 20 40 60 80 100 Frequency MHz
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 But Wait, There’s More TIA has two draft addenda out for ballot now -
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.”
Two-connector Topologies? Other Topologies. . . (i.e. with cross-connect and/or transition point)
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.”
So What Do the Giga-guys Say? IEEE Draft P802.3ab/D2.0 Physical layer specification for 1000 Mb/s operation on four pairs of Category 5 or better balanced twisted pair cable (1000BASE-T) 40.8 Link Segment Characteristics 1000BASE-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.
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
Pair 1 Pair 2 100 or 1000 Mb/s 100 or 1000 Mb/s Pair 3 Pair 4 NIC HUB Performance Specifications4 Pair Systems • Additional Performance Parameters • Power Sum NEXT • Power Sum ELFEXT • Return Loss • Skew
PS NEXT PS FEXT EMI Return Loss 4 Pair Systems1000BASE-T Noise Sources 250 Mb/s Full Duplex 1000 Mb/s 1000 Mb/s HUB NIC • EMI - Non-cancelable by DSP • NEXT - Cancelable by DSP • NEXT - Cancelable by DSP • Return Loss • FEXT - Non-Cancelable by DSP
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 Informative not requirements Additional Transmission Performance Specifications for 100 Ohm 4-Pair Enhanced Category 5 Cabling Cabling StandardsANSI/TIA/EIA-568-A Draft Addendums
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
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
Current Industry Definition Category 6/Class E Link and Channel Performance Specifications* *Draft figures only and subject to change
80 70 60 50 dB 40 30 20 10 0 0 50 100 150 200 ACR for Category 5 , 5+ , 6 Channel Cat 5 ACR 3.1dB min.. NEXT Loss Cat 5+ ACR 6 dB min. (prop.) Cat 6 ACR 18.3 db min. (prop.) Attenuation Frequency MHz Cat 5 Cat 5+ Cat 6
UTP System Installed Channel Cost Comparison Installed Cost Materials and Labor* Cat 6 Enhanced Cat 5 127% 100% 92% * Estimated labor by BICSI 08
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.
STP or PiMF • STP or STP-A = 150W IBM Cabling System • PiMF = 100W “Pairs in Metal Foil” cables • Individual pairs shielded to improve NEXT performance • Overall shield used to improve EMC performance Shielded Cable Types • FTP = Overall foil shield • S-FTP = Overall foil shield plus an additional braid • 100W, CAT3/4/5/6 • Shield used to improve EMC performance FTP or S-FTP
Backbone RequirementsEffects 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
?? SW 2.5 Gbps ATM SW LW 1000 Base-F 1.2 Gbps ATM ? LW FDDI 155ATM Fast Ethernet 622 ATM SW 10BASE-F Cabling Evolving Backbone Cabling Platforms Bandwidth Data Rate MHz•km Mb/s 10,000 SM 1,000 500 100 160 10 1984 1986 1988 1994 1997 2000
Gigabit Ethernet Optical Fibre Physical Layer Interfaces Media Access Control (MAC) full duplex and/or half duplex Gigabit Media Independent Interface 1000BASE-T Copper PHY encoder/decoder 1000BASE-X 8B/10B encoding/ decoding 1000BASE-LX LWL Xcvr 1000BASE-SX SWL Xcvr SMF-5km 50um-550m 62.5um-550m 50um-550m 62.5um-220m 802.3ab physical layer 802.3z physical layer
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
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.
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
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
Max 90 m Max 500 m (fibre) Optical BackbonesDistributed Network Architecture TC TC Equipment Room Server TC = Telecommunications Closet
Switched 1000 1000.0 Switched 100 100.0 Switched 10 10.0 Shared 100 1.0 0.5 Shared 10 1, 2 or 5 Segments 62.5/125 0.2 Parallel 50 Links 50/125 0.1 Single mode 0 0 10 100 1000 10,000 100,000 FDDI 100BaseF 155 ATM 1000BaseF 1.2Gbps ATM 2.5 Gbps ATM Next Gen Apps. Intra-building Optical Backbones Sizing for Performance Bandwidth growth User Requirements in Mbps Based on 100 Users/closet and 500m cable length Backbone Requirements in Mbps
Max 300 m total (fibre) Interconnect or splice Equipment Room Server Optical Cabling Centralized Network Architecture TC? Pull Through TC = Telecommunications Closet
Switched 1000 Switched 100Base F Switched 10 Shared 100 1.0 0.5 Shared 10 1, 2 or 5 Segments 62.5/125 0.2 0.1 50/125 0 0 0.5 Switched 10Base F Switched 1000BaseF Switched 100Base F Shared 10Base F CNA Optical Cabling Sizing for Performance 1000.0 100.0 10.0 User Data Rate in Mbps Bandwidth growth 1.0 10 100 1,000 Independent of # of users Based on 300 meters cable length CNA Data Rate in Mbps
Next-Generation Optical Connectors (Jacks) 568SC ST Small-Form Factor LC MT-RJ VF
Commercially Available Fiber Cable To Hub The Next Standard 2-Fiber System On board Commercially Available Fiber Cable
568SC MT-RJ Plug / Jack Size Does Matter! • Duplex Plug-Adapter-Plug Interface. • Specialized cut-outs • Depth to cable transition = 1.95” • Surface Mounted interface • Drop-In replacement for existing • 8-position modular connectors • Depth to cable transition = .926” • Fits INTO J-Box
I/O Real Estate is Recovered Fiber Card Count Halved Small Form Factor ConnectorsSolves the Electronics Issue
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
Horizontal Cabling- Typically Category 5 but quickly changing to Enhanced Category 5 as minimum requirement Intra-building Backbone- Typically 62.5/125 multimode fiber but 50/125 fiber is recommended for greater bandwidth Inter-building Backbone- Typically multimode fiber but should include some single mode fiber for longer distances CONCLUSIONCabling Sub-System Trends
End of Session #28 EE 8301 ST750-NDr. Baker E-Mail Address: hbaker@seas.smu.edu Videotape Problems: vthelp@seas.smu.edu