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How To Meet ANSI/TIA-4966 Standards and Futureproof School LANs

Stéphane Bourgeois

In schools, high-speed, high-density local area networks (LANs) must meet the demands of students, faculty, staff and parents. Networks in these environments support everything from e-learning and streaming rich media content to converged voice/video/data and mobile computer labs.


Not only are the occupants different in an educational building, but schools often have longer useful lives than commercial buildings. This means that proper, futureproof network infrastructure is even more important.

 

college computer lab, educationAs a result, cabling requirements in educational facilities may be more complex than in an office or other type of commercial building.

 

To address these unique requirements, ANSI/TIA-4966 was released in May 2014, and it describes the distinct requirements for entrance facilities, equipment rooms, telecommunication rooms and enclosures, backbone and horizontal cabling and work areas in educational facilities. Nothing in the ANSI/TIA-4966 standard conflicts with ANSI/TIA-568 standards for commercial buildings; instead, it provides more specific information about how to properly cable an educational facility - whether it's a college or university, high school or K-12 institution, school library or residence hall.

 

There are a few notable differences we think you should understand when comparing ANSI/TIA-568 and ANSI/TIA-4966 standards.

 

Difference #1: Multi-User Telecommunications Outlet Assembly (MUTOA)

Because some course curriculum is better learned in specific classroom configurations, it's common for classrooms to rearrange from year to year, semester to semester or even month to month. Dynamic environments with lots of movement often call for longer patch cords, and place added stress on patch cords. Even though they're the most vulnerable part of a school's network, patch cords are often overlooked. When damaged, they can be the cause of unplanned downtime.

 

MUTOAs essentially place a consolidation point at the end of the horizontal link in a fully accessible permanent location in an area that will be regularly reconfigured. This reconfiguration may lead to patch cord lengths that are longer than what the standards typically show.

 

The ANSI/TIA-4966 standard allows for 16 feet of 24 AWG stranded patch cord or 13 feet of 26 AWG stranded patch cord. If patch cord length exceeds those numbers, permanent link distance must be de-rated by 0.2, because stranded cables attenuate up to 20% more than solid conductors. In other words, for every extra foot of stranded cable being used, 1.2 feet must be subtracted from the permanent link. The good news is that there are bonded-pair solid conductor patch cords that eliminate the need to de-rate the length of a permanent link. Moreover, bonded-pair patch cords offer superior performance and exceed the TIA mechanical stress reliability test.

 

Difference #2: Wireless Access Points

The second area that the ANSI/TIA-4966 brings to light has to do with wireless access points (WAPs). The standard recommends that all areas within an educational building have wireless coverage (unless it's prohibited due to security reasons).

 

 

Referring to ANSI/TIA TSB-162-A for wireless accent point cabling, ANSI/TIA-4966 provides a capacity table that calculates the number of WAPs needed based on expected occupancy and the type of building in an educational facility. For example, in typical school buildings with occupancy levels between 201 and 300 people, 14 WAPs are recommended. In residence halls, that density increases.

 

ANSI/TIA-4966 WAP Capacity Chart

Occupancy
(Expected Number of People)
Wireless Access Points Needed
1-25 1
26-50 2
51-75 3
76-100 4
101-125 5
126-200 9
201-300 14
301-400 18
401-500 21

 

Planning for maximum flexibility may lead to patch cords that are longer than 16 feet, requiring them to be length de-rated if using stranded conductor patch cords. Replacing the patch cord with a bonded-pair solid conductor patch cord, as mentioned earlier, will allow for maximum flexibility and distance.