Network Standards.

Introduction

This document will outline the current requirements for the network-cabling infrastructure as used with-in the University of Sussex IT Services (ITS), as well as giving the previous requirements with the reasons behind their succession. It will also state the requirement of the University of Sussex (ITS) with regard to the acceptance for connections of any new network installation to the University Campus Network.

Current ITS Tender Document.

ITS have a tender document that covers the points below in more detail as well as putting them into context with other aspects of the installation procedure. This tender document can be downloaded in PDF format .

Current Category 6a and (legacy) Category 5e Network Standard.

Below are the current basic ITS required standard for new network infrastructure installations.

  • Category 6a of Siemon's Z-MAX™ system range is the de-facto minimum currently approved cabling system on campus.
  • Only Category 6a components from the Z-MAX system range from the Siemon Company are to be used, this is to ensure compatibility with existing installations, maintain manufacturers installation warranty and reduce the cost of cable maintenance, any proposed installation must be demonstrated to be compliant with the current approved system, clearly identified in the tender response, and supported by manufacturers documentation and test certificates.
  • Note: Standard Category 6 (not the same as Category 6a) is explicitly not approved for use on Campus.
  • Terminations should be carried out to TIA-568-A pin allocation codes,
  • Legecy Category 5e (Enhanced) systems are only to be used where the current cabling system is also Category 5e and needs to be added too, this is not an alternative to installing Category 6a for new builds, refurbs and cabling refreshes.
  • Installed Category 5e (Enhanced) systems should be capable of initially supporting 100Mbps applications, again this is not an alternative to installing Category 6a for new builds, refurbs and cabling refreshes.
  • Any Category 5e (Enhanced) installation should be to ANSI/TIA/EIA-568-A and ISO/IEC 11801 transmission requirements,
  • ITS currently require that the Siemon MAX System should be installed.
  • ITS currently requires that data cabinets should be of at least 780mm wide and 600mm deep and are mounted on a plinth to provide cable access. In most situations a glass front door is preferable. The cabinet should be of a suitably sturdy construction.
  • ITS currently requires that a minimum of one double outlet be installed in every habitable room of 8 metres squared, and a minimum of two double outlets in every habitable room of more than 8 metres squared,
  • ITS currently requires that outlets are housed in a white ABS backbox if wall mounted or within the centre compartment of three-channel mitre trunking,
  • ITS currently requires that on main runs cables should be protected by white trunking with a minimum internal size of 38mm x 25mm. Where skirting/dado trunking is used the system must be able to accomadate a minimum of a 35mm deep backbox and have top/bottom compartment minimum external dimensions of 50mm deep x 36mm high,
  • ITS requires that individual cable lengths should be no more than 80 metres. This distance does not include patch cable or drop cable lengths,
  • ITS requires that Commando power sockets to be used AND that the power feed is filtered.
  • Cables should be routed back to 24 way patch panels in suitable cabinets containing adequate cable management facilities,
  • Cables should be clearly and uniquely identified at wall outlets and patch panel ends as well as on the patch panel and wall outlet surfaces,
  • Power should be provided by at least one double filtered 13 amp mains outlet,
  • ITS will require all cabling to exceed the fire performace rating euroclass E(ca), as of 1st of July 2017 under EU regulation 305/2011.
  • ITS will require clear documentation and diagrams of cable routes and identification, which should cross reference to TDR cable tests of at least Category 5 link standards. These should be provided on hardcopy and electronic media and

    • Required System Information.

    The required system is the Siemon Max System.

    The Siemon "Z-MAX " System represents potentially the fastest Category 6a networking infrastructure to ITS today. If a total Siemon system is installed including patch leads etc. the system is well capable of running advanced applications up to Gigabit Ethernet and ATM 622 Mbps speeds due in part to it's full Power Sum (1) compliance.

    The cable used in this system is Siemons own brand of 4 pair UTP which comes in a low smoke zero halogen purple jacket, again which will put it apart from other non data cables run in the same location. These cables satisfy ANSI/TIA/EIA-568-A and ISO/IEC 11801 Category 5e transmission requirements. Where there is a conflict in performance standards specifications, Siemon cables satisfy the more stringent requirements.

    The Pronet part number is 9C5L4 (page 12-2) although Siemon do have a number of cable partners whose enhanced Category 5e and Catogory 6a products are acceptable. These companies include Draka, Berktek and Belden. Most installations on campus use either the Siemon or Draka branded cable.

    The termination blocks require no special tools to be purchased in order to be used. The cores of the cable are laid into a clear plastic housing, and then the housing is clicked into the carrier module. The splitting of pairs is carried out within the carrier module making termination even easier than the ITT Canon 808 system.

    Another great advantage of the Siemon "Z-MAX" System is that up to six cables can be terminated within one British standard single gang box (85mm x 85mm). This makes for a much greater potential density of outlets in a much smaller footprint.

    Unlike the previous two systems, if a fault should occur with the outlet, the offending termination block can be removed from the front of the faceplate without the need to unscrew the entire faceplate and possibly disturbing the other terminations in the box.

    1. With ever increasing transmission speeds over UTP, and the utilization of all four pairs in a link, the crosstalk performance of the cabling system becomes critical. This is especially important for systems using all four pairs such as 100BASE-T4, and may be crucial for the pending IEEE 802.3 Gigabit Ethernet networks being designed to operate over category 5e cabling.

      Power Sum crosstalk evaluations, originally developed for testing 25-pair cable, can be applied to 4-pair cabling systems to more accurately reveal the actual crosstalk performance for 4-pair applications. When all four pairs are used for signal transmission individual pair-to-pair performance evaluations fall short of determining the overall crosstalk effect. The total crosstalk effect on any given pair is the sum of the crosstalk from each of the other pairs in the cable

Updated on 15 February 2022