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Implementation Creating a craft-friendly, low-cost Ethernet distribution system fully rated for Gigabit Ethernet consists of the following: Ethernet Distribution Frame, providing the cen

Data-Center Connectivity

Patch Panel Introduction and Selection Tutorial 293

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Ethernet Distribution Frame

Introduction

Centralized Cross-Connect System for

Managing Ethernet Data Services

Situation

Ethernet-based data services offer the opportunity to create differentiation, command premiumpricing, and earn higher margins for such value-added data services as transparent LANs, storagearea networks, and virtual private networks Extending native 10/100Base-T and Gigabit Ethernetservices across the LAN, WAN, and MAN means data services are less expensive to deploy,

provision quickly, and offer exceptional reliability and security Yet as the Ethernet distributionsystem grows with more routers and switches, all of these advantages can be quickly erased by apoorly designed cabling and connectivity architecture

An effective ethernet data services business model includes the following goals:

• Create a flexible, carrier-class Ethernet delivery system, and

• Decrease operating costs of Ethernet delivery

Reaching these goals is contingent largely upon building the correct architecture to supportEthernet data services

Solution

Achieving the dual requirements of lower costs and carrier-class services is possible by creating acentralized cross-connect patching system with an Ethernet Distribution Frame (EDF) An EDFprovides a cross-connect field that ties together all Ethernet network elements, providing a

common craft interface for performing adds, upgrades, and rearrangements on Ethernet services

In this simplified architecture, all network elements have permanent equipment cable connectionsthat are, once terminated, never handled again Technicians isolate elements, connect new

elements, route around problems, and perform maintenance and other functions using permanent patch cord connections on the front of the EDF cross-connect bay This craft-friendlydesign supports cost-effective growth and change in the Ethernet distribution system

semi-Figure 1

Active Network Element Bays

Ethernet Distribution Frame

Active Network Element Bays

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Ethernet Distribution Frame

Introduction

Benefits

• Lower operating costs As compared to direct connect or interconnect designs, the EDF

cross-connect reduces the time it takes for adding cards, moving circuits, upgrading software, and

performing maintenance Factory assembled cable assemblies and patch panels reduce installation timeand ensure consistent quality In addition, this high-density interface for Ethernet distribution not onlymaximizes active ports but also conserves valuable floor space

• Improved reliability and availability Permanent connections protect equipment cables from daily

activity that can damage cables Moves, adds, and changes are effected on the patching field instead

of on the backplanes of sensitive routing and switching equipment, enabling changes in the networkwithout disrupting service With the ability to isolate network segments for troubleshooting andreroute circuits through simple patching, Operations gains time for making proper repairs duringregular hours instead of during night or weekend shifts

• Competitive advantage The EDF enables rapid changes to the network Turning-up new service is

accomplished by plugging in a patch cord instead of the labor-intensive task of making multiple hard-wiredcable connections As a result, cards are added to the network in minutes instead of hours, decreasingtime to revenue and providing a competitive edge—faster service availability—in the marketplace

• Investment protection Unlike direct connection of Ethernet elements, the logical EDF cross-connect

scales easily As elements are added, transport methods changed, and new technologies implemented,the EDF remains constant, providing the common craft interface for managing Ethernet distributionwithout service disruption

Implementation

Creating a craft-friendly, low-cost Ethernet

distribution system fully rated for Gigabit

Ethernet consists of the following:

Ethernet Distribution Frame, providing

the central location for cross-connecting all

Ethernet network elements in a data center

with semi-permanent connections Each EDF

consists of the following ADC equipment:

• 19" or 23" UEF zone 4 rack

• Glide Cable Management system,

consisting of vertical cable managers

installed on the sides of each rack as

well as upper and lower crossover

troughs

• Category 5e patch panels, RJ45/RJ21x,

providing up to 864 available Ethernet

ports per 7' rack

• Category 5e patch cords for creating

semi-permanent cross-connections

Active Network Element Frame

houses both active equipment and one or two distribution panels It provides permanent connectionsfrom active Ethernet equipment to distribution panels and from distribution panels to the EDF

• 19" or 23" UEF zone 4 rack

• Glide Cable Management system, consisting of vertical cable managers installed on the sides ofeach rack as well as an upper crossover trough

• One or two Category 5e patch panels, RJ45/RJ21x, mounted at the top of each bay with active network elements mounted below

• Category 5e patch cords for making permanent RJ45 connections between Ethernet equipment anddistribution patch panels at the top of the bay

Connect Patch Cord

Cross-Permanent Equipment Cable

Vertical Cable Manager

Permanent Patch Cord

Ethernet Distribution Frame

Active Network Element Frame

Active Ethernet Equipment

Patch Panels

Vertical Cable Manager

Figure 2

Ethernet Distribution Frame

Introduction

Permanent Equipment Cables, providing permanent connections between the EDF and distribution

panels in each Active Network Element Frame

• Factory terminated and tested RJ21x 24-pair Category 5e cable assemblies, up to 90 meters in length

Optical Extension Platforms, providing E/O and O/E conversion for distances greater than 100 meters

between active equipment May also be used for interoffice transport, for transport to customer

premises, and for interface with Ethernet network elements that require fiber optic interfaces

• Rack mount, high-density design, mounted in or adjacent to EDF and active equipment bays

Fiber Cable Management, for termination, splice, and storage of fibers where media conversion occurs.

• Rack mount FL2000 panels, wall mount FL2000 boxes, or high-density Fiber Management Trays, all with integrated cable management that connect and protect fibers

Power Distribution, for protection of critical active equipment such as routers and switches in the

Ethernet distribution system

• PowerWorx®power distribution products include options for suppression of power line noise,uninterrupted power, and fusing for multiple amperage equipment from a single rack unit design—all with NEBS Level 3 certification and a 15 year warranty

Design Issues

• All cable assemblies, patch cords, and patch panels should be rated Category 5, 5e, or 6 to ensureGigabit Ethernet performance, per EIA/TIA 568-B.1 standards for LAN cabling While GigabitEthernet is designed to run on Category 5 or higher cabling, Category 5e and Category 6 cablesand components are preferred for new build-outs

• Cabling distance between active network elements should be no more than 100 meters, whichincludes both permanent cables and semi-permanent patch cords Patch cord length should be lessthan 10 meters due to attenuation from stranded cable Distances greater than 100 meters requireoptical transport and media conversion at both the EDF and active bays

• Due to TIA standards that limit the proximity of connection points, limit the number of passiveconnection points between active equipment to four with length between EDF and active

equipment of at least 15 meters to minimize electrical interaction between patch panels

• Proper routing, management, and protection of cables and patch cords in both the EDF and activeelement bays is essential for carrier-class reliability and availability A system of vertical cable

managers with integrated slack managers not only offers proper management of cables, but alsoprovides increased bay density as compared to systems using horizontal cable managers Verticalcable managers should be sized 8 inches wide, except for inter-rack applications that require 10- or12-inch widths

• Select a standard patch cord length of less than 10 meters for the EDF and use slack managers invertical cable managers for routing and storage of extra cable lengths (see Figures 3 and 4) Thisensures that the cross-connect is easy to administer while providing protection for patch cords

• Choose preconnectorized patch panels with RJ45 interfaces on the front and RJ21x interfaces onthe rear Punchdown connectors (110) are reliable, but take more time to install and are prone toinstallation errors such as cross wiring that disable ports Gold-on-gold contacts between modularinterfaces on patch panels are pre-assembled cable assemblies ensure reliable and consistentperformance

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Ethernet Distribution Frame

Introduction

Figure 3 Connect ports to the same side of the same EDF

cross-connect bay using vertical cable managers with slack

managers for handling extra cable lengths.

Figure 4 Upper and lower crossover managers with vertical cable managers enable connection of ports on opposite sides of the EDF cross-connect bay.

• Where E/O conversion is required, media converters should feature clear separation of optical,electrical, and power supply cables to ensure system reliability Distributed power architecture is alsopreferred for improved performance, reliability, and system availability Built-in intelligence enablestime saving in installation and troubleshooting with full view of UTP and optical link integrity fromone end of the circuit

• System reliability depends upon proper management of fiber cables Fiber panels and boxes shouldinclude removable angled retainers as well as integrated splicing and slack storage In addition,single circuit access to fibers provides improved system reliability and availability by reducing thechance for damage to adjacent fibers during routine maintenance of individual fibers

Conclusion

Earning customers for value-added data services requires innovative offerings, a competitive price, andsuperior reliability and availability Extending native Ethernet across the LAN, WAN, and MAN opens thedoor for new data services However, building an infrastructure that keeps operating costs low whileproviding exceptional reliability and 99.999% availability requires a centralized cross-connect EDF

designed to manage growth and change without disrupting service

2

2

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Ethernet Distribution Frame

Ethernet Distribution Frame

7' EIA 19" UEF Zone 4 Rack Glide Cable Management Adapter

2RU Horizontal Cable Manager

Media Converter Fiber Management Tray

48-Port Category 5e Panel

8" Glide Cable Management

Bottom Crossover Trough

ADC’s Ethernet Distribution Frame (EDF) forms a central patching location between active Ethernet networkelements By creating a centralized craft interface for adds, upgrades, and rearrangements on Ethernetequipment, the EDF enables change without service disruptions This central patching location provides alogical and easy-to-manage infrastructure due to two design characteristics:

• All network elements have permanent equipment cable connections that are, once terminated,never handled again

• All changes, circuit rerouting, upgrades, maintenance and other activities are accomplished usingsemi-permanent patch cords on the front of the EDF cross-connect bay

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Ethernet Distribution Frame

Glide Cable Manager

Features

• Integrated front, rear, horizontal, and vertical cable management

• Patented rib cage design eliminates horizontal support trays and bars

• Supports up to 912 ports on a single rack

• Built-in bend radius protection ensures network integrity

• Designed for quick and easy moves, adds, and changes

• Optional slack managers available for 8-, 10-, and 12-inch widths

• Fits standard EIA rack with three-inch channel

• Used for single rack or as inter-rack unit

• Optional crossover troughs and horizontal cable managers available

• Optional EIA-standard horizontal support bars available

Description

Glide cable manager, vertical mount –

to equip both sides of a 7-foot rack, order

two Glide Cable Manager units

6", front only, without slack manager

6", front only, with slack manager

6", without slack manager

8", without slack manager

10", without slack manager

12", without slack manager

8", with slack manager

10", with slack manager

12", with slack manager

Crossover trough, 2 RU

Crossover trough, 4 RU

Black metal covers

41" x 6", four per pack

41" x 8", four per pack

41" x 10", four per pack

41" x 12", four per pack

Black metal cover, hinged

41" x 6", two per pack

O r d e r i n g I n f o r m a t i o n

Ordering Number

ADCCMVIB06F-2 ADCCMVIBS06F-2 ADCCM-06 ADCCM-08 ADCCM-10 ADCCM-12 ADCCMS-08 ADCCMS-10 ADCCMS-12 ADCCMTG02 ADCCMTG04

ADCCMVIBC06B4 ADCCMVIBC08B4 ADCCMVIBC10B4 ADCCMVIBC12B4 ADCC06-2

Glide Cable Manager with Slack Managers

Cover in Black Metal Glide Cable Manager Shown in Cabinet

Horizontal Cable Manager

Installation Drawing for Glide Cable Manager, Cabinet Mount

Glide Cable Manager, Cabinet Mount

Slack Manager Stabilizer

Ethernet Distribution Frame

Glide Cable Manager

Description

Glide cable manager, cabinet mount –

ships 4 per pack

6" x 10 RU

6" x 20 RU

Glide cable manager, cabinet mount,

with cable retention – ships 4 per pack

ADCCMVIB-3CB20-4 ADCCMVIB-6CB20-4 Notes: Equips standard 7' cabinet with front or rear cable management.

Order two 4-packs to equip front and rear of cabinet.

With slack managers, 3 RU

With slack managers, 4 RU

Rear cable management bar, 19"

ADCCMHIB-2U ADCCMHIB-3U ADCCMHIB-4U ADCCMHIBS-3U ADCCMHIBS-4U

ADCCMRSB ADCCMRSB-4 ADCCMVIBSP

ADCCMVESB06 ADCCMVESB08 ADCCMVESB10 ADCCMVESB12

EB-17B EB-35B EB-70B Note: Stabilizer used at end of line-up for each Vertical Integrator section.

Welded steel relay rack, 3" channel, black

Welded steel relay rack, Zone 4 rated, black

Spacing

19" EIA 19" EIA 19" EIA 19" EIA 23" EIA

With all the choices you face as you design your network and select equipment, including availableEthernet patch panels, it’s easy to become confused and frustrated Ultimately your choice ofEthernet panels should fit the applications you plan to run ADC wrote this short tutorial to guideyou through these decisions, to make them as painless as possible and offer you the best solutionfor your network.

First, let’s ask a few key questions Your answers will help guide you in the decision process Next,

we will briefly discuss each of the most popular options available so you can draw conclusions based

on your network needs

Discovery Questions

• What applications are you or do you plan to run on this network? 10/100Base-T? 1000Base-T?

• What type of network are you designing? Data center? Data backbone? LAN?

• Is the project a new network installation or addition to existing network?

• Is the installation being built to expand existing capacity with current data capabilities or is itfor new, faster data applications?

Answers to these questions will guide you to a particular cable type, a particular data patch panel,and the means to terminate the cable into the patch panel — whether the terminations into thepatch panel involve “punchdown” cable terminations, pre-made telco-type multipair cable ends,

or standard RJ45 cable ends

The general guidelines for network transmission capabilities segment the data network; datacenter and data network backbone system applications require the highest level of transmissioncapabilities, while feeds to work areas generally require a bit less However, all networkconnectivity should be designed with only the highest network engineering standards available

Category 5, 5e, and 6 Cabling

The Telecommunications Industry Association (TIA) standards forming group consists of a variety

of industry experts including connectivity and cable manufacturers, distributors, installers, and endcustomers The TIA determines certain transmission characteristics that must be met to qualify acable for certain network applications

Category 5 cabling is currently the most prevalent wiring in existing buildings Electrical

characteristics defined by the TIA specify near end cross-talk (NEXT), attenuation, and return loss

to 100 MHz The TIA Technical Services Bulletin (TSB) 95 recommends additional criteria for far endcross-talk (FEXT)

Category 5e is currently the minimum TIA recommended category of wiring for new installations.

Electrical characteristics for NEXT, FEXT, attenuation, and return loss are specified to 100 MHz NEXTperformance is slightly better than category 5

Category 6 is gaining popularity for new installations Electrical characteristics for NEXT, FEXT,

attenuation, and return loss are specified to 250 MHz Improvements in all electrical parameters arepart of the higher TIA Category 6 standard

Category 7 cabling is a developing standard The International Standards Organization (ISO) is leading

the standardization efforts for this new individually-shielded, overall-shielded, 4-pair cable withtransmission specifications referenced to 600 MHz The cable end interface will probably be somethingother than the familiar RJ45 connector, mainly to differentiate the Category 7 installation from existinglower-bandwidth infrastructure

So, which should you use? There is quite a bit of misleading information in the industry on this subject,the biggest myth being that Category 6 is required to run Gigabit Ethernet over copper (1000Base-T).Actually 1000Base-T was designed by the IEEE to run on Category 5 As long as the Category 5 isinstalled according to TIA-568-B standards and meets the testing criteria in TIA TSB 95, 1000Base-Twill perform satisfactorily on Category 5 However, as of this writing, the TIA recommends Category5e over Category 5 as the minimum cabling for new network infrastructure installations

When do I use Category 6? Does the application standard (i.e., Gigabit Ethernet, 10G, etc.) specifyCategory 6 as a minimal requirement? The TIA is making recommendations to the IEEE 802.3ae andthe 10 Gigabit Ethernet Alliance, who are currently working on 10 Gigabit cabling systems, that any

10 Gigabit Ethernet designed to run on copper cabling use Category 6 because of its improvement insignal to noise The good news is that Category 6 is backward compatible and will have no troublerunning existing applications such as 10/100Base-T and 1000Base-T

Cable Type Summary

The chart below summarizes the industry standard UTP cable types used in current networkinginstallations

In addition to the UTP cabling described above, you should understand the issues of cable shielding,and stranded versus solid cable

Shielded vs Unshielded Twisted Pair

Unshielded twisted pair (UTP) cabling provides immunity to electromagnetic interference (EMI) with theproperties of the two conductors that make up a transmission pair being twisted together When UTPcabling encounters electrical interference, the noise crossing the twisted pairs is cancelled by the twists

in the cable (called “Common Mode Rejection”, a subject outside the scope of this introduction).Standard Category 5, 5e and 6 cables contain four unshielded twisted pairs of conductors For10BASE-T and 100BASE-TX applications, only two pairs are used, one for the transmit circuit and onefor receive circuit For 1000BASE-T (Gigabit Ethernet) all four pairs are required

The term “shielded twisted pair” cabling can be misleading There are actually two methods of

shielding a twisted pair cable Screened twisted pair cable (ScTP) provides an overall screen or metal foil around the four pairs of conductors, but each individual twisted pair is unshielded Shielded

Category Test Frequency 10/100BaseT 1000BaseT Future Applications Relative Cost

Cat 5 100 MHz Yes Yes No $ Cat 5e 100 MHz Yes Yes Maybe $ Cat 6 250 MHz Yes Yes Yes $$ Cat 7 600 MHz Yes Yes Yes $$$$

Twisted Pair cable (STP) has each individual pair shielded, plus an overall screen around the four

individually shielded pairs This makes a very expensive and hard to install cable - the legacy token ringIBM Type 1 cable and Category 7 are examples of STP cable STP cable requires metal end connectorsand metal jacks that bond the cable shield to earth ground to carry the interfering signals safely awayfrom the signal conducting pairs – failure to connect the cable shield to earth ground results in theshield coupling the interfering noise to the conductors, providing very poor transmission performance.Most of the world uses UTP cabling, with some exceptions located in a few countries in Europe

Stranded vs Solid Conductor Cable

Stranded cable is flexible and often used for patch panel jumpers and work area connections Strandedcabling is used for shorter patching applications for its flexible cable construction, but also exhibitshigher attenuation due to the smaller diameter conductors, and as such should not be used for long,permanent installations Solid conductor cable is used for the “horizontal” cable runs from thetelecommunications room to the work area wall outlet The typical gauge for Category 5e cable is 24AWG Category 6 is 23 AWG - the larger conductor diameter improves attenuation characteristics andsignal-to-noise ratio versus the smaller conductor diameter of Category 5e

Wiring Schemes, T568A vs T568B

Wiring schemes also raise a variety of questions:

Q: What’s the difference between T568A and T568B?

A. The only difference is the positioning of the Green and Orange pairs of wires (see figure 1)

Figure 1

Typical RJ45 cable ends, T568A vs T568B

Q: Is there a performance difference between T568A and T568B?

A: No Both wiring schemes have to meet the same performance criteria

Q: Why two schemes?

A: The reason is outside of the scope of this paper but it is related to old telephone legacy issues.All you really need to know is that there are two schemes, and how to deal with them