What part of the telecommunication and datacommunication process does the Cable Management Branch manage?
The Cable Management Branch's primary responsibility is for the installation and maintenance of all Horizontal, Vertical and Outside Plant cabling to support Telecommunications/LAN Closets, TEL/LAN Work Area Outlets and CATV outlets. These tasks encompass all on-site and off-site NIH facilities in the Washington, DC Metro Area totaling nearly 100 sites.
The Cable Management Branch interfaces and coordinates with the Telephone Infrastructure Branch, Network Engineering Branch, DES Project Officers, Construction Personnel and NIH Staff to ensure that ANSI/TIA/EIA Telecommunication and NIH Standards are met and maintained.
In one year alone, the Cable Management Branch staff have been responsible for the installation of:
- 24,586 Work Area Outlets
- 5,988,543 ft of 4 pair cable
- 33,795 ft of Conventional fiber
- 6,600 ft of "Air-Blown" fiber
- 3,450 Outside Plant cable
What does Category 5e, Category 6 wiring and Gigabit Ethernet mean?
Categories 5, 5e, 6, and Gigabit Ethernet Standards
TIA (Telecommunications Industry Association), ISO (International Organization for Standardization), BICSI (Building Industry Consulting Service International), and others have collaborated on the Category 5e and category 6 standards. At this time, category 6 cabling, connecting hardware, and cabling performance requirements are firmly specified and unlikely to be revised further and should be ratified this year. Industry activity is currently focused on developing and improving high frequency test methods.
Category Cat 5 enhanced (CAT 5e)
The new TIA standard released in 2000 is TIA 568B. In this standard, Category 5 is replaced by Category 5e. Category 5 is no longer supported in horizontal cabling applications. Category 5e is a published standard, currently designated as TIA 568A-A5. While Category 5e is limited to 100 MHz, it adds all the new performance parameters, and has higher performance in NEXT(Near-end Crosstalk) than its Category 5 predecessor.
Addendum 5 to ANSI/TIA/EIA-568-A specifies enhanced Category 5, or Category 5e, performance requirements. These requirements are recommended for new category 5e cabling installations and are now the minimum standard for category 5e cabling. Addendum 5 also addresses the minimum equal level far-end crosstalk (ELFEXT) and return loss requirements necessary to support developments in applications technology and defines the minimum performance needed for a "worst case" four-connector channel to support applications that utilize full-duplex transmission schemes, such as Gigabit Ethernet. To ensure additional cross talk headroom for robust applications support, this addendum also specifies power sum performance requirements for category 5e cables, links, and channels.
Category 6/Class E (CAT 6)
Category 6/class E standards describe a new performance range for unshielded and screened twisted-pair cabling. Category 6/class E is intended to specify the best performance that UTP and STP cabling solutions can be designed to deliver. Category 6/class E is specified in the frequency range of at least 1-250 MHz. For category 6/class E, the 8-position modular jack interface will be mandatory at the work area and will require matched and balanced hardware and cabling. Category 6/class E will be backward compatible, which means that applications running on lower categories/classes will also be supported. If different category/class components are to be mixed with category 6/class E components, the combination shall meet the transmission requirements of the lowest performing category/class component.
Category 6 represents the best possible performance for future specifications for unshielded twisted pair cabling. Category 6 sets much tighter requirements on cabling than Category 5 or even Category 5e. First, the measured frequency range extends to 250 MHz, in contrast to Category 5's 100 MHz. Second, the performance requirements are significantly better than Category 5E at the same frequencies.
Gigabit Ethernet
1000BASE-T is full duplex, but unlike 100BASE-T, it uses all four pairs in the cable simultaneously. Each pair is responsible for supporting 250 Mbps of information. Pulse Amplitude Modulation (PAM-5) with 4-level signaling is used to lower the channel bandwidth requirement to 125 MHz, though the maximum power density is well under 100 MHz. This is why it can be run on 100 MHz-rated cabling.
1000BASE-T requires that the cabling meet some tough criteria:
- Signals must arrive at the far end strong enough to have survived attenuation effects
- Noise sources cannot create confusion at the receiver
- Signals sent from one end on all four pairs must arrive at the far end at roughly the same time
How do I check the status of my TSR (Telephone Service Request) or DelPro?
To check the status of a telephone request:
- Call the Telephone Infrastructure Branch Help Desk at 5-HELP (5-4357) 8 a.m. to 5 p.m. Monday through Friday except Federal holidays.
Please provide the Remedy ticket number or DelPro number with you inquiry.
Remedy is the work request tracking database. The Remedy ticket number is a unique identifier used to track each job to completion. The Remedy system sends the ticket number to the requestor by e-mail when the Help Desk creates the work request.
How are the TSR and DelPro different?
The Telephone Service Request (TSR) is a form used to request telephone equipment and services when no purchase is involved.
Delegated Procurement (DelPro) is the mechanism that IC Administrative Officers(AO) utilize to purchase telephone services and products. Contact your AO to purchase telephone equipment and services.
Want general computer assistance?
Call the NIH Help Desk at 301-301-496-4357.
