Cabling choice Fibre/Cat 5 or something else

[ranj]

Hi

 

Was wondering what peoples opinions are on this.

 

I am going to be looking at changing the schools backup solution from tape backups to NAS storage. The plan is to have the NAS box on the other side of the school as an off site backup effecitively.

 

Problem is the distance is about 150-200 metres. Fibre is what a lot of companies are recommending just because there is less likely for faults and copper maximum distance is only 100m but could be extended by using a hub for example.

 

What sort of costs do you think would be to run some sort of cable, be it copper or fibre about 150metres. I would want a secondary cable run as well as a redundancy.

 

It be interested to hear other peoples views on this.

[Geoff]

Fibre, given the distance and what the link is going to be used for.

[bishopsgarthstockton]

Fiber 8O

[webman]

Definately fiber, considering the 100m limit of Cat5e/6.

[broc]

Fibre, for distance reasons but also I believe there are some electrical wiring regulations that prohibit connecting buildings with copper data cables, not sure of the details exactly (earthing, different power phases & lightning strikes comes to mind).

 

We implemented something similar to what you are proposing a year or two ago when we ran fibre into our sports hall from the main school building. This was justified for staff in PE to be able to use electronic registration but it also let me install a budget SATA based server in a store cupboard for DR backups. We have just installed fibre to a couple of demountables in the playground too as they had to dig a trench for power & alarm cables anyway.

[plexer]

Fibre here for all external backbone connections.

 

For maximum redundancy run 2 four core fibres via different routes?

 

Ben

[Midget]

We have lots and lots of fibre each link at 1GB/s. If i get some more money and learn how to do it, i'll try to upgrade some of them to 2GB/s

[limbo]

I would definately go fibre bearing in mind the amount of data - the closer you get to the 100m on copper the worse the packet loss can be so data can still get through at over 100m but anything from 80m onwards can be considerably slower.

 

The Fibre itself is not hugely expensive - but it is what you stick at each end that can be the expensive bit. We upgraded our fibre links between our three main buildings (two 200m runs). These were 16core fibres and we are currently using eight cores accross each run to give 2 x 4Gb links.

 

Of the toal cost less than a third was the fibre - the rest was the kit for each end.

[SteveT]

always, always, always fibre!!!

 

Indeed, the regulations do not allow for copper between separate buildings. Something to do with earthed voltage differences AFAIK. This was discussed on here last year I think but I can't find the relevant thread at present.

[bossman]

A hub! do people still use these outmoded pieces of equipment?

well all i can repeat is what other people on the forum are advising and that is fibre 10G spec if you can get it.

[krisd32]

I asked a similar question last year the distance wasn't the same but the principals will be!

http://www.edugeek.net/index.php?name=Forums&file=viewtopic&t=3732

[tosca925]

Fiber all through the backbone.

[sidewinder]

All fibre here, the only copper link we've got just goes upstairs which is about 20 metres.

 

About the external CAT5 though (I asked this on the other thread but didnt get a reply) why then have our cablers been allowed to run external CAT5 to a few terrapin buildings here? There would be no point running fibre to them as theres only 1 PC in each, and the distance from the other building is only a few metres

[plexer]

Probably because no-one told them not too?

 

That seems to be quite common, who were the cabling company?

 

Ben

[Ric_]

The reason for not running copper outside is that it is prone to lightning strikes... thus you need surge protectors. You also need to use high quality, external-grade cable which is significantly more expensive than your standard solid-core stuff.

[CyberNerd]

Linking buildings with copper does create a voltage difference between the buildings - causing problems and possibly damaging equipment.

Also think of rust and other damage to the cable.

[staceyh]

Fibre, every single link we have in the whole school is fibre, cost around 15K, but when you have 9 buildings, 16 data cabs, 36 Switches, 41 Radio Port site wide WiFi, 12 Servers and a partridge in a pear tree you need fibre .... there's peace in the light