Cat5e cabling

[sloughman]

Hello, i wonder if anyone can help.

 

What is the optimum, ie max, recomended amount of PCs sharing a cat5 cable. At my school there is a classroom with 16 PCs that connect to a switch that feeds back to the server room cab via a single cat5 cable. Would switching to fibre for the switch to server cab run increase performance noticeably ?

 

Thanks in advance.

[m25man]

This has nothing to do with the cable as long as it is less than the theoretical max length reqd for your data rate.

With only 16 nodes in your class you shouldn't need anything else but if you did 2 uplinks and a link aggregated pair would suffice.

[MikeGilbert]

Cat5 isn't a cable, it's a standard If the cable hasn't been installed, terminated and tested to Cat5, it's not necessarily going to work properly.

[sloughman]

So the basic upshot is as long as cable is shortish run, significantly less than 50m, number of nodes makes no difference ?

[foofighterjim]

<100m for cat5e, personally I wouldn't go longer than 80m. The key question is how much bandwidth is that one connection using? If you are getting 1gig to the switch and the 16 computers are sharing (effectively) 1gig of bandwidth then you should be fine. If it is 100mb to the switch then you will probably run into problems. Edited October 22, 2013 by foofighterjim

[sloughman]

Forgive my lack of knowledge , how would I know the bandwith amounts ?

[sonofsanta]

Fibre isn't any faster than copper in the majority of cases. You can spend a lot of money either way to get faster, but most implementations these days are 1gbps.

 

The only advantage fibre has is length - about 600m instead of an upper limit of 100m for copper (although the recommendation is normally to stick to 90m or less, allowing 5m of cabling each end for patching in).

 

If the copper run is > 90m then performance may well be increased by fibre as packet loss would be reduced.

 

Forgive my lack of knowledge , how would I know the bandwith amounts ?

 

Look at the front of the switch, it'll likely tell you - probably with yellow/green flashing lights and a small line of text telling you what each colour represents. It will probably be green = 1gbps, yellow = 10/100mbps, but if it's an older/cheaper switch it may top out at 100mbps. Sometimes you will get a cluster of four ports that are 1gbps for backbone connections whilst the majority of ports for clients are limited to 100mbps.

Edited October 22, 2013 by sonofsanta

[Kitkatninja]

...The only advantage fibre has is length - about 600m instead of an upper limit of 100m for copper (although the recommendation is normally to stick to 90m or less, allowing 5m of cabling each end for patching in)....

 

I'd also like to add fibre's immunity to electrical noise as an advantage

Edited October 23, 2013 by Kitkatninja
US vs UK spelling

[detjo]

We had a similar set up here.

We have a 'main' building and 3 outer buildings, which contain the library and a bunch of classrooms. All 3 outer buildings were cabled to a cab in the main building, which then went to the server room via one Cat5e. All switches installed were 10/100 and it was painfully slow in the classroom furthest away. Upgrading to 1Gb switches mad sooo much difference

[plexer]

Cat5 isn't a cable, it's a standard If the cable hasn't been installed, terminated and tested to Cat5, it's not necessarily going to work properly.

 

So what do you call the cable then?

 

Ben

[witch]

So what do you call the cable then?

 

Ben

....sweetie-pie.....

[foofighterjim]

So what do you call the cable then?

 

Ben

 

When is a cable not a cable?

 

When its un-terminated and untested cat5.

[detjo]

When is a cable not a cable?

 

When its un-terminated and untested cat5.

It's still a cable.

 

Speaking to sales assistant:

"Can I have a reel of ..!"

"Reel of what?"

"Well it doesn't have a name coz it's not been terminated and tested cat5"

[Dos_Box]

Moving to Wired Networks forum.

[plexer]

All of the components that are needed to make up an installation are built to the spec for that proposed standard, so cat5e cable, cat5e plugs, cat5e jacks, cat5e patch panel.

 

No good sticking a cat5e jack on a cat6 cable and testing it as cat6.

 

When it's all installed and terminated it is then tested to make sure it conforms to those standards as an installation.

 

Ben