Structured Cabling

Category 5/6 Structured Cabling is a standard that enables you to connect all of your telecomms and IT peripherals in a single, easy to manage, network cabling infrastructure.

So, how does an installation take place?

Well initially, with the help of an office floor plan, you need to determine where all your telephones, fax machines, modems, PCs, Printers, etc, need to be installed. Once this information is available, your next step is to choose a location that can become a communications room or area (if one does not already exist).

A single cable can now be run to each location (one for each outlet) that you originally identified on your office floor plan. Depending on the size of your building and the nature of your business, a large number of cables may well need to be run which means specific cabling routes will need planning and cable trunking will almost certainly be required.

It is very easy to underestimate the amount of outlets that you are going to need around your building and it is prudent to install additional outlets for future expansion or in the event of office furniture relocations.

Once all the cables have been installed they need to be terminated. Special sockets can now be installed on the cable ends that are situated around your building, these have an RJ45 presentation. The other end of the cables are presented together on patch panels, which in effect, are rows of RJ45 outlets, usually housed in a cabinet structure. Each socket is labelled with its own personal number and its corresponding patch panel outlet is marked with the same number in the patch cabinet.

After the structured cabling is finished and tested, you need to make this new infrastructure work for you. Into your new patch cabinet, you need to present your LAN in the form of a bank of switches or the older type hubs, and finally you require the same type of presentation in the patch cabinet from your telephone system.

All that's left to do now is plug into the sockets, all your telephones, PCs etc. and make a list of the socket numbers you have used. At the patch panel end, you have to now connect the relevant socket outlet presentations to either a telephone extension or your LAN switches. This is done by using patch leads, which are leads with RJ45 plugs on each end, to make the final connections necessary.

Is there anything better than CAT5e?

There are currently three emerging standards: Category 5 Enhanced (5E), Category 6 and Category 7. Category 5 Enhanced (C5E), like Category 5 is a 100MHz classification. However, the performance requirements of a Category 5 Enhanced system are more stringent.

The purpose behind this standard is to provide an improved Attenuation to Crosstalk Ratio (ACR) and return loss, compared with conventional Category 5 solutions. This is partly achieved by reducing the NEXT levels in the cables and connecting hardware. Signal interference and corruption is therefore further reduced, improving signal integrity.

To ensure that this new standard will be supported by emerging technologies, additional testing criteria and equipment have been introduced.

The need to transmit increasing amounts of data has placed an additional strain on Category 5 cabling systems. To reduce data congestion, by increasing speed, certain emerging protocols utilise all 4 pairs of standard 4 pair cable, splitting the data equally on each pair. For example, in Gigabit Ethernet the data is split equally onto each of the 4 pairs. This means that 250 Mega bits of data are transmitted along each pair. Since more than one twisted pair can be transmitting at any one time, the total amount of interference on any one pair must be measured.

This type of measurement is called Power Sum, and it is applied to NEXT and ACR