What's the truth about Cat5 right now?

[jmair]

We have our backbones using fiber, then to cat5. Cat5 for single machines in the labs, and cat5 on our Gigabit switches going to our servers and to the firewall > t1 router.

 

A few years ago, there was cat6 and cat5e (something never put in place here). Am I missing out? Am I losing anything by using cat5 for some the high traffic switch ports (like the fileserver and internet)?

[Michael]

CAT5e supports upto 1000Mbps. CAT6 is essentially the same cable, but is tested to a higher standard. Allegedly, CAT6 is capable of 10Gbps but I have not seen this anywhere.

 

To answer your question - so long as you're using quality CAT5e cables and they're properly installed (not twisted or wrapped up) you should be getting the full benefit of Gigabit speeds.

The make/quality of your switches also play a big role too. You can buy Gigabit switches relatively cheap these days, but the manageability, the throughput and on board memory all play a role in maximising speed.

[powdarrmonkey]

Cat6 extends Cat5 by making the transmission band 250Mhz (2.5 times the width), meaning less likelihood of errors through interference and, if you have cat6 equipment throughout, higher future speeds (category 7 is rated to 10Gb/s I think).

[m25man]

There is a lot of CAT5 Cable out there that can handle Gigabit with ease, however a shortage of FEP has occurred several times in the history of plenum-approved (CMP-rated) copper cable.

During each shortage, the prices rose dramatically, and hybrid constructions were introduced using a mix of other insulating materials to make up for some of the material shortfall.

 

Today, that may not be possible because the higher-performance copper cables (Category 5e, Category 6, 6a and 7, 7a) cannot function properly with the resultant delay skew caused by different insulation material properties.

 

Your conventional Wiremap tester is not going to tell you this, you need a TDR to verify the ability of the cable if you do not know what it's history is and you want to put Gigabit down it.

 

With so many Gigabit Ports around nowadays it's really easy to find your self connecting a desktop back to a Gigabit switch with rubbish cable and patch leads.

 

Gigabit needs all 4 pairs, one bad crimp or punch down and your screwed!

[IanT]

The future is Cat7

[jmair]

Thanks for the info!

[Ric_]

@jmair: [ame=http://en.wikipedia.org/wiki/Structured_cabling]Structured cabling - Wikipedia, the free encyclopedia[/ame] outlines the basics too (link off to different categories).