Structured cabling to support Cisco based networks

[calmichael]

I know this is not directly related to conifguration or product selection, but I am hoping that someone can weigh in.

What differences other than being partial of a particular vendor can anyone offer on why one would choose to use cabling produts (Cat5e/6/etc) from vendors such as Ortronics, SystemMax, Berk-Tek, etc versus a vendor or independant contrator who will do it "in-house" and will issue certification and on demand replacement; expecially at half the cost of a "named" structure cabling vendor?

Thanks

[phaon.reid]

I have worked in data centres where they have insisted on a particular brand of cabling.  It could be annoying having to pay an inflated price, and also perhaps suffer from extended lead times.  On occasions it has been necessary to put in one set of cabling temporarily, and then replace it all when the "official" cabling arrives.

I can think of two reasons why such a policy might be adopted.

Firstly to preserve a uniform appearance.  Different manufacturers' cables will be slightly different colours and may use slightly different terminations or boots on the connectors. Therefore a tidier overall appearance can be achieved by sticking to a single supplier.

Secondly bad experiences with second-rate suppliers might lead to a decision to stick with a firm which is considered to be reliable.

Hope this helps,

Phaon

[scottmac]

While each vendor has category-compliant products, they each will present a different profile in sweep tests used to verify certification.

For example, characteristic impedence is permitted a plus or minus ten percent variance for the swept frequency range. Vendor A may be below the line at the lower end of the sweep, but still be within the permissable variance/tolerence while Vendor B is above the line (when I say "line" i'm talking about the target, the goal, the specified median) and Vendor C can vary back and forth across the for the full range.

When Vendor A creates panels and jacks for its cable, it can adjust (through the design & manufacturing process) the panels and jacks to compensate for the below-the-line values and create a balanced, overall improvement to the cabling SYSTEM performance. The same for Vendor B and C ... because they know the absolute performance characteristics for their cable, they can compensate to improve performance of thier system in the other components. This is generally why it's a good idea to stay with one vendor's product, end-to-end. i.e., putting Vendor A's jacks and / or panels on vendor B's cabling may result in an amplification of Vendor B's "above the line" stats and actually push the system outside the Category-rated envelope.

I used characteristic impedence as an example, but the concept applies to any of the basketfull of cabling component specifications.

Also remember that "structured cabling" was designed for more than just Ethernet networking. Once vendor's cabling system may offer better specs for applications other then Ethernet networking (like video, RF, or or serial / terminal operations).

Many cabling component providers will warranty the performance of their cabling system, as long as all primary components are part of that vendor's current cabling system catalog. AT&T used to (maybe still does) warranty their professionally installed and certified cable plants for ten years (I think it was quite a long time, for cabling). Any performance failures shown to be attributable to the (professionally installed and certified) AT&T cable plant was fixed at no additional charge. If you've ever chased ugly cable bugs, you can understand what kind of cost savings this can represent.

Staying within one vendor's component system contribute to the likelihood that the overall cable plant will operate at full, optimized performance.