The Telecommunications Industry Association (TIA) may only hold three meetings a year, but it does get plenty of significant work done. Some say the results (which are tested and retested) are slow and “behind the times,” but it’s easy to forget that what comes out of the TIA are standards written to ensure minimal performance. People need to meet these standards when designing or installing products. Many techniques or products go much further, but at least they need to meet these minimal standards.
Here is an update on eight major work items accomplished for you in 2003.
1. Electrostatic discharge
Work was started and finished in 2003. This work was to educate users on how to mitigate interference from ESD in their local area networks.
Status at the end of 2003: The original write-up done by TIA for BICSI ended up as a formal TSB (Telecommunications Systems Bulletin); TSB-153 “Static Discharge Between LAN and Data Terminal Equipment.” It explained what ESD was: charges generated when different materials come into contact and are then separated and the amount of that charge could be significant. An insulator (between two conductors) would store the charge and a good conducting path would allow the stored charge to dissipate (disperse) rapidly. If large amounts of potential energy were discharged rapidly, damage could occur. That is referred to as ESD. They also showed that Category 5, 5e and 6 cables probably handled the charge about the same.
Some guidelines were included to help users avoid ESD:
• Follow the equipment manufacturer’s spec sheet
• Install equipment according to the manufacturer’s specs and guidelines
• Assess your site’s susceptibility to ESD (low humidity, static generating building materials)
• Use a grounding patchcord to discharge the static charges in the cabling to earth ground
• Leave equipment connected to the cabling to avoid buildup of static charges in the cabling
This standard is now published and available for purchase through Global Engineering Documents; see the telecommunications standards at www.global.ihs.com.
2. Category 3 cabling
The previous and very familiar Category 3 cable used to be the Grade 1 recommended cable for residential use in the Residential Cabling Standard (TIA-570-B).
Status at the end of 2003: The committee clearly decided/agreed to remove the Category 3 cable from the Grade 1 Category because it was not capable of handling home networks that were included under Grade 1 cabling. The older Category 3 cable was only for telephone services and did not allow for multi-use outlets. The group revised Grade 1 Residential Cabling to be defined as Category 5e cable with Category 6 recommended.
This newly revised standard should be published in early 2004.
3. DTE power over cable
At first, there was a need for a performance standard for cable that would be carrying DC power out to terminal devices, such as VOIP (Voice over Internet Protocol) phones. After work was contributed from the TIA, the IEEE 802.3 committee ratified an extension to the original Ethernet standard that is called Power over LAN (POL) or Power over Ethernet (POE) in the IEEE 802.3af standard. Ethernet technology (IEEE 802.3) was the original standard for passing data over a network (over two of the four wire pairs in a Category 5 cable).
Now the new IEEE 802.3af standard allowed power to be delivered simultaneously over the other two spare wire pairs. The IEEE standard maxed out delivering a total of 13W. Note that IP phones and wireless LAN access points usually consume 3.5 to 10W. Manufacturers could then manufacture equipment to that standard knowing that the amount of power carried to the device, was IEEE compliant.
Status at the end of 2003: Along with that, TIA worked on developing guidelines for UTP cables to carry this kind of power also. The TIA’s standard is still being worked on (not finalized yet) for power consumption to be no more than 10 watts of power per pair. That would mean the ability to deliver a maximum of 20 watts. This is being done to have a standard of wider breadth and depth to handle future equipment requirements in the 13 to 20 watt range.
IEEE has published their standard, IEEE 802.3af-2003. TIA continues to ballot their version and this should come out in early 2004.
IEEE requested that projects get started as soon as possible and after much debate, TIA got two addenda planned out that would support (by writing specs for the cable and connectors) IEEE’s work on 10GBASE-T (10 Gbps baseband Ethernet transmission).
The first Addendum, TIA-568-B.2, Addendum 10, is currently titled “Augmented Category 6 Cabling.” IEEE requested this work to support 10GBASE-T transmission over 100m of structured balanced twisted pair copper cabling. Test procedures are to be included too, and the project will include extending the frequency range to 625 MHz (before it was up to 250 MHz).
Manufacturers of equipment that handles or will handle 10GBASE-T want these specs settled so they can sell their products.
Another project IEEE is very interested in is TIA’s TIA-568-B.2, Addendum 11 for “Investigation of Balanced Cabling Performance Up to 625 MHz.” This is for Category 5e (over which Category 6 has a distinct advantage) and Category 6 cabling and addresses the hard-to-solve alien crosstalk interference problem at this speed. There may be some concerns for installers because of the effects (“coupling”) from bundling (an example would be wrapping a group of cables with a tie wrap) on the UTP cables. In fact, the variation (of order) in bundling may turn out to be more important than the cable category.
Status at the end of 2003: Work is continuing on both of these projects, and the important results will be reported on during 2004 TIA meetings.
To keep you abreast of this technology’s challenges, Alien cross talk (AXT or Alien NEXT) is caused by emissions from one cable affecting the other pairs in the other cables. This assumes the cables are adjacent to each other. If UTP (unshielded twisted pair) cables are bundled together for a distance of more than 15 meters, AXT can be a concern—it is a random interference or noise. It’s also a critical spec for determining channel capacity.
5. Fiber testing for OLTS
This standard was to be published after the final comments were checked out. It was written to help the user when using a Fiber Optic Loss Test Set in fiber testing. A major goal was to clear up what the difference was between Tier I and Tier II testing, so installers and customers alike would know which options to choose based on what they felt was necessary.
Status at the end of 2003: Tier I testing mainly addresses measurement of attenuation and sometimes can include length and polarity. It also referred people to the ANSI/TIA standards 526-14A, Method B and 526-7, Method A.1 for the standards to take attenuation measurements for multimode and singlemode cabling. Tier II testing was clearly stated as “supplemental” to Tier I and was for an OTDR trace of the cabling link. It explained and helped users comply.
This standard will also be published in early 2004.
6. Data center cabling design standard
This standard was sent out to ballot for comments. This may be in its final stages and is the first standard to help people with the design and layout of a data center. What makes it more generally useful is that it revolves around a generic type of cable, versus a proprietary solution. There is much to learn about the elements of a data center, never mind how it should be configured to work at its best.
Status at the end of 2003: This standard continues being commented on and may be issued later in 2004.
7. Telecomm Enclosure
The TE standard was discussed, but was not fully accepted. There came a need for this standard because the TE was being seen on the market. As development continues, its purpose and design are becoming clearer—it might seem similar to a Telecomm Room, but it serves a different purpose—and above all, it probably won’t replace the requirement for one Telecomm Room per floor.
Status at the end of 2003: This will be a realistic option for the office environment, especially the modular office, and should be finalized in 2004.
This Addendum to TIA-568-B.1 should be agreed upon and published in 2004.
8. Power separation
Work on this was started. This is a long-awaited area of research for people in this industry. When and where to separate data cables from power cables has now become more critical with the high-speed networks popping up everywhere.
Status at the end of 2003: This information will start by appearing in the update to the Pathways and Spaces standard, TIA-569-B, when published; it may also appear in the new data center cabling standard because of the high-level of activity in the data center, which is related to the main commercial building cabling standard, TIA-568-B and it would be covered in the upcoming “C” series. EC
MICHELSON, president of Jackson, Calif.-based Business Communication Services and publisher of the BCS Reports, is an expert in TIA/EIA performance standards. Contact her at www.bcsreports.com or firstname.lastname@example.org.