Rewiring an entire school

[localzuk]

So, me and the boss have been spitballing an idea to get rid of the dozen wall mounted eyesore cabinets we have around the school and having all IT infrastructure go back to a single, purpose built, server/comms room.

 

We have about 600 connections around the school, so not a particularly huge number.

 

However, these are spread out over 4 buildings.

 

Now, my thought on this was to have a new purpose built server room built onto the back of one of the existing buildings, with raised flooring, proper cooling (something like using the heat to heat the underfloor heating in that building during winter, and some form of natural heating during summer, augmented by backup aircon should it be needed.

 

However, the cables would all need to get there, so this would mean we need to bury them. Would this be feasible? Underground conduits from each building leading back to the new room? How deep would they need to be buried?

 

Thoughts? Ideas? I'd guess such a scheme would end up costing us around £100k, but would free up several store rooms, make our infrastructure sane and sensible and properly secure all the equipment.

[jamesreedersmith]

Major limiting factor of all copper cables eg gig/100meg would be 100m limit!!!

[plexer]

When you are spread over multiple buildings or buildings when a single run would exceed the specs I can't see how you can remove all of the satellite cabinets, sure you can probably remove some of them but at a huge cost.

 

Ben

[SHimmer45]

fibre connections from your main comms cab to satellite ones for specific blocks id say would be the most feasible way of doing this and would give flexibility within each block. though this isnt what you are trying to achieve would it be an idea to look at smaller cabs which are less of an "eye sore"

you are going to be limited by the cable run length of copper being 100m point to point which isnt alot when you actually walk the distance out over an actual school site

Edited January 19, 2011 by SHimmer45

[localzuk]

Major limiting factor of all copper cables eg gig/100meg would be 100m limit!!!

 

Good point. This would limit us somewhat. Our site isn't that large, even with multiple buildings, but this would mean we'd need 2 rooms - one at each end of the site.

 

We already have cabinets joined by fibres, and this is what my boss wants rid of as they are ugly and ruin the look of the school.

[plexer]

Paint them pretty colours?

 

Ben

[localzuk]

Paint them pretty colours?

 

Yeah, not gonna work... They'd still be there, intruding into rooms.

[gshaw]

Is it really worth all that work just for the look of a few patches of wall? We used to have 1 comms cabinet in the server room, another in the back of our office connected via fiber then everything cabled from there. Tbh it was a nightmare, if you had trouble with the cables you've got massive lumps of Ethernet running everywhere instead of a couple of fiber cables.

 

Surely the money would be better used on upgrading the infrastructure in future. Maybe you could look at relocating the cabs into less visible places instead or getting one of those office-type server cabinets that's in the style of a standard cupboard or something along those lines?

[CyberNerd]

If there all in one or two rooms you get the advantage of high bandwidth stacking cables. 54GB/s backbone could work out cheaper than 10GB/s fibre

[glennda]

I would suggest finding some nice cuboards - Here i have loads which are hidden at the top of tall cuboards.

 

But if you are rewiring and you find 1 decent cuboard per block this will remove them from the classrooms.

 

Something I wish had be thought of better here rather then having so many small ones around the school centralise them into a decent patch panel.

 

Couldn't get away with a rewire here i have nearly 2 thousand sockets! (not all used yet tho as some are put in for when we go to a voip telephone system)

[localzuk]

Is it really worth all that work just for the look of a few patches of wall? We used to have 1 comms cabinet in the server room, another in the back of our office connected via fiber then everything cabled from there. Tbh it was a nightmare, if you had trouble with the cables you've got massive lumps of Ethernet running everywhere instead of a couple of fiber cables.

 

Surely the money would be better used on upgrading the infrastructure in future. Maybe you could look at relocating the cabs into less visible places instead or getting one of those office-type server cabinets that's in the style of a standard cupboard or something along those lines?

 

Our infrastructure is already pretty darn good, equipment-wise.

 

The idea would be that everything would be in one place and would be simpler to manage - ie. properly laid out cabinets with cable guides, labelling and purpose provided stuff, not just 'ad-hoc grown' network cabinets.

 

I've mentioned the cabinets you mention, but again, they still take up space in teaching areas. Space which is needed too much already.

 

And we don't have any spare stores to put anything in, its an old building and space is at a premium.

 

The other option is fitting a loft out for comms...

[webman]

Are there no offices or cupboards at all where you could discreetly mount them? There's nothing wrong with network cabinets, and lots of network cabinets doesn't mean it can't be managed properly.

[dhicks]

proper cooling (something like using the heat to heat the underfloor heating in that building during winter, and some form of natural heating during summer, augmented by backup aircon should it be needed.

 

Heated swimming pool? If that's too large, how's about a hottub?

 

Thoughts? Ideas?

 

If you simply want to hide the switch cabinets you can get nice-looking cabinets designed to look more like wardrobes or normal school cupboards. They're accousticly dampened, too, so they hide the noise of a switch's fans.

 

You could also look at replacing wired connections with wireless. I spoke to a couple of companies at BETT that reckoned their wireless solutions could completly replace a wired network, although I'd want some careful clarification of any sort of garuntee or service level agreement and maybe some spare equipment standing by.

 

--

David Hicks

[nicholab]

Well you would need a cabler to come in and discuss the best way of moving to a rationlised layout. If you could pull back cabling to cab locations you it would be cheaper also doing it a whole project it will cost you less than single points.

 

One thing we do is we use short patching so we go

panel

switch

panel

panel

switch

panel

[K.C.Leblanc]

What happens if you have a major catastrophe and the main building is placed out of commission?

[glennda]

maybe some spare equipment standing by.

 

Maybe a long fiber lead

[Butuz]

Can we see a floor plan?

 

I can see what you are trying to do and why you are trying to do it.

 

Unfortunatly some school layouts just mean that it is not possible to get away with a single cabinet to serve the whole school. If you've only got 4 buildings you don't sound in too bad a position. You could get away with 1 x main cab in server room and 3 x satelite cabs linked via 10 gig fibre. That would be ideal performance wise and shoudn't cost too much.

 

We have 13 buildings and as the infrastructure has been slowly addded to over the years - cabinets and fibre everywhere. I would like to rationalise the cabinets as much as possible but realistically there isn't much rationalisation that can be done without taking a bulldozer to the site and starting from scratch.

 

Replacing all cabs and re-wiring with cat 6 would be a luxury for most schools IMHO. You have to ask - how much value will you get from that estimated 100k spend. How much will teaching and learning quality improve via the use of that 100k/ The answer to both questions is not much / barely any. As such - I'd have to make DAMN sure there wasn't any other way that the 100k could be better spent before I committed to the network cab project.

 

Either way - I am jealous that you are even able to propose such an idea!!

 

Butuz

[Soulfish]

We rewired our entire school this summer. We put in one new network cabinet (for a total of 10 - one on each floor, plus the server room), but kept the current network cabinets in their existing locations. In total we put in approximately 1300 network points, one 8-core fibre run and replaced all network cabinets for a cost of around £60,000. We already had 8-core OM3 fibre runs to all the other network cabinets.

 

Unfortunately the distances were to great for us to even think of running it all back to a single point, however if we had any spare hidey holes/large cupboards it would have been good to have been able to relocate some cabinets to them. Unfortunately we don't so everything still wall mounted in various classrooms.

[pete]

This really depends on how populated your cabinets are, but:

 

1) You can get slimline cabinets that mount kit vertically (switchports are at the bottom / top). Like the Thinline model here: Wall-Mount Enclosed System Table - At Chatsworth Products, Inc.. Assuming you can get sufficient switchport density per cab, that may be an option.

 

2) The wallspace in broom cupboards / understairs / storerooms is under-used. There's normally one within 30 metres of where you need to provide network access.

[localzuk]

Search for TA24 5RH on Google Maps, that'll give you an idea. Only change from the google image is the long hut on the playground is now gone, and in its place 4 classrooms as an extension to the topmost building of the site.

 

There are no spare cupboards - the cleaners/caretaker have 1 store of their own, and that's a shed.

[localzuk]

Ok, so, distance aside (as we would settle on 2 rooms instead, which would cover the site), anything else?

 

We can't really do 'slimline' cabinets, as each one around the school is at least 12U and we use very deep switches (HP Procurve 2650s or deeper in some cases (PoE models).

 

The advantage I can think of is the ability to increase the backbone from a couple of 1Gbit fibres to 10Gbit relatively cheaply, and then link the switches with 2 Cat5e cables for 2Gbit connectivity to that. It'd effectively increase the network speed to at least double what it is now without much new equipment.

[maniac]

You have to be careful running copper between different buildings because of the potential earth difference between them, it can cause problems if you're not careful.

 

I can understand the need to rationalise cabinets as I did the same when I started where I am now - we had cabinets everywhere when I started! Slowly over the last 2 years I've managed to get rid of 3 of them so it's a bit more sensible now. However I would never consider getting rid of all of them back to a central location unless that location had proper decent easy to follow cable trays/trunking going out to all the locations necessary, otherwise it makes adding additional network points very difficult and very expensive. The best I would hope for would be 1 cabinet in each building and a good multi core fibre link back to the main comms cabinet, but having all the copper connections running back to a cabinet in another building is an un-wise thing to do in my opinion.

[Ketlane]

If you go for underground connections - from hard experience make sure that the installers make both ends of the conduits they bury completely rat-proof. For some reason our local rats think that fibre-optic stuff is as tasty as anything else in the known universe - we had two breaks before we had things totally protected!

[MatthewL]

Keep your satellite cabs, gives you some resilience in case you have issues around the school site. One of our biggest sites has the main server room and has a number of satellite 42U cabs, can often make fault finding a little easier too with switches.

[teejay]

As said previously, length of copper is 100m max, but this can also be reduced by interference from other stuff along the route that's near the cable. I presume you would be following paths of existing cabling, if so, either buy or rent a fluke tester that can do certification testing and check for current levels of interferance on the cables. You then need to determine a main run route to your proposed cab location, pull a cable through and test. All these tests need to be done when the school is in use and the majority of electrical equipment is switched on, especially lights. If you're not getting results well within the upper limits for noise then you need to reconsider or find new routes through and re-test.