We are having a nice new drama and arts block built here at Alton Convent School. We need some networking equipment to put into it. I've spoken to the chap doing the wiring, that's all taken care of - we've sorted out where the network points are going to go for classrooms, IT suites, wireless access points, IP cameras, the lot. Everything will be wired (probably with cat6 cabling) to a cabinet in the back of a storage cupboard in the middle of the building.
What should I be looking for by way of switches, and how much is a reasonable amount to spend? Our networking equipment currently consists of a bunch of desktop switches connected together (under desks, in the ladies loo, etc). We have two Dell PowerEdge 2724 switches, which cost around Â£150 each. These are 24-port gigabit switches, they have two SFP slots for connecting fibre, and they have a basic web management interface. Seemingly this web management interface allows us to do stuff like port mirroring, so we can attach a monitoring PC to see what traffic is going through the switch.
My plan was to simply buy some more of these switches, total < Â£1000. I got a quote from SwitchShop for a similar number of switches for around Â£8000. The salesperson didn't seem to be able to explain why, exactly, Â£8000 worth of switches would be better than Â£1000 worth.
Does anyone know what makes more expensive switches worth the money? I understand that the more expensive the switch the more bandwidth you get across the backplane, so the more data the switch can handle (the 2724 can seemingly handle 48Gbps, which sounded okay to me). I also understand that if we need to add further switches we'll be doing so by plugging one end of an ethernet cable into one switch and the other end into another switch, there's no way of directly linking the backplanes on the cheaper models.
Is that all you really get for your money, increased backplane speed and "stackability"? Are there any must-have features I really should have in a modern network in a school?
This thread will be a hundred posts long in no time, so I will get in quickly.
Simply put, you get what you pay for.
Management and warranty thats my top criterior when selecting switchgear.
Bear in mind that many of the advanced features of HP & Cisco rely on thier neighbours to use the same OS.
Mixing and matching can bring limitations.
Modular chassis can really pay dividends when you know you will expand but are not sure when and by how many ports.
An average secondary school installing a typical Core/Edge solution with 10GBe interconnects could cost circa Â£81,000 including OM3 Fibre installation.
Im currently working on a football stadium project with HP which with a modular core and stackable edges will cost around Â£50k
Â£8k probably wouldn't buy a decent core yet alone equip the entire campus.
Well as an example of the features we use on our HP procurve 2650's and our core 5406zl, we make use of:
1. 802.1Q VLAN's, tied in to RADIUS authentication
3. RADIUS authentication (at the moment just MAC based, but will probably move to 802.1x)
5. Port mirroring
6. Layer 2 routing for inter-vlan routing
7. Connection rate limiting for preventing rapid virus spreading.
These are all pretty important items I would say for a relatively basic school network now.
Does the dell switch do all these? Also, what is the warranty like on the dell? Failure rate?
Personally, I would pay for the more expensive HP gear due to the fact HP have been in networking longer than Dell and know how to build superb switches. If I had the money I'd go further and say go for cisco as they are the daddies of networking.
The cheap stuff does seem to be improving -not long ago you wouldn't have seen QoS, aggregation or VLAN support on budget switches. When people are spending a fortune running fibres & cables though it seems like a gamble to put in potentially inferior switches.
We have 3com kit throughout and they do have some handy management features e.g. the software will map out the live network and show network health based on a few parameters - even down to the level where it told me one of the switches had a fan on its way out. It also shows which workstations are connected on which switch ports.
We can customise some of the more arcane switch settings which sometimes gets you out of a jam (e.g. configuring spanning tree and broadcast storm control). The basic point there is that you don't want to come to a point where you need to customise a particular feature that your switches have hard-coded. Being able to backup configs to a file and restore them to a replacement switch is also handy - not sure if the budget models do that yet.
I love the latest Netgear kit with the lifetime warranty it's exceptional value for money however we are yet to see a modular chassis and until we do they will never be seen a a serious contender.
I have a site with no money and the need to share 4 servers with duplexed NIC's to 16 Fibre links and the best they have is 2 x Netgears 7312's by the time you have trunked 4 ports on each together to give you the band width I have my 16 ports but nowhere to connect my servers!
So you end up with a horrible hotch potch of cascades and trunks that fills half a rack and still can't deliver more than 4GB throughput!
But it only costs Â£4k in cheap switchgear.
An HP 4000/5000 or 8000 Chassis will easily expand to support this requirement but costs as much as a reasonable car!
It really hard to sell this concept to a Bursar who has built his own network for Â£50 from PC World.
If a school has to budget for 180k pa to hire supply teachers, why is it seen as ludicrous to spend 20k building a half decent network core!
Thanks everyone for your answers, very helpful indeed. There seems to be something of a mis-match between how much money the school was expecting to spend on networking equipment and how much you people would recommend spending. I don't think our bursar is going to be able to go much over Â£1,000 worth of equipment, compared with estimated costs mentioned here ranging from Â£10,000 (localzuk, "pretty basic") to Â£80,000 (m25man, "average").
Fibre installation - the main costs for this seem to be to be the groundworks part of things, i.e. digging holes in the ground. That's taken care of (it's a new building), so all we have to do is tell the contractor where to connect the fibre. Am I asking the contractor to install one strand of 50/125 fibre cable, or should I be asking him to install more/better cables while he's at it?
Modular chasis would seem to be out, they cost too much. Will I get better performance (less latency?) by linking switches together with fibre rather than copper ethernet cables?
Reliability/warrenty/support: I figure at Â£150 a switch, if one breaks we'll simply chuck it out and get a new one. It might be an idea to have a spare one around as a hot-swap spare, though. The other option would be to use a specialist resller such as SwitchShop and see if they offer any kind of after-sales support package. Can anyone recommend other suppliers (I'm also trying some chap recommended by BT when I rang up to see about the ADSL connection)?
The Dell 2748 offers 144Gbps of backplane bandwidth for 48 1Gbps ports. I don't quite get how that works... surley 48 1Gbps ports should produce a maximum of 48Gbps total data?
RADIUS authetication - do I actually need this? My plan was to simply let any computer that wanted to connect to our network and concentrate on making sure each individual server was secure. Same goes for VLANs - is there any need to seperate networks, can't I just make sure each server is secure?
QoS - the Dell switches support this. I don't think we have any network traffic that needs prioristsing, though (our VoIP telephone system will have its own switches provided by the telephone system company).
STP - I don't think we're going to be able to afford more than one link between each switch, so there'll be no need for the switches to be able to find the most efficient route between themselves.
Port mirroring - the Dell switches support this, although reading the documentation I think they can only deal with a limited number of ports at a time. Is it more efficient to use a network tap anyway?
Backup / restore of setups - no, the Dell switches don't handle this. This was something mentioned in a review I found. I guess if a switch does conk out it's just going to take me a little while to get a replacement working, even if I do have one to hand to slot straight in.
Network Access Protection - this seems to be a protocol used on networks with Microsoft Windows servers, which we don't have.
> Do not forget your cabinet inter-connect specifications.
> Choose the wrong cable and you may have to pay twice as
> much for your GBiC modules. Measure twice pay once!
Thanks. Any idea what sort of cables I should be asking for, then?
> I have a site with no money
...ah, that sounds like us...
> and the need to share 4 servers with duplexed NIC's
> to 16 Fibre links and the best they have is 2 x Netgears
> 7312's by the time you have trunked 4 ports on each
> together to give you the band width I have my 16 ports
> but nowhere to connect my servers! So you end up with
> a horrible hotch potch of cascades and trunks that
> fills half a rack and still can't deliver more than
> 4GB throughput! But it only costs Â£4k in cheap switchgear.
Hmm, the port aggregation thing is an idea - I could run four bits of copper cable from the server room to the switch in my office and the ICT suite. Is it worth running four bits of fibre cable between the switch in my office and the new building, do you think?
> It really hard to sell this concept to a Bursar who has
> built his own network for Â£50 from PC World.
...that sounds like us too!
> As for stacking - yes, it's a really good idea to get a
> dedicated switch interconnect if you want to stack some
> workgroup switches. Just like the Cisco 3750 with it'
> stackwise connections.
Which fiber installation training would you recommend (internal MMF terminstion and install only).
If your going to do it yourself, RTFM that you have just downloaded and understand fully what it is you want to achieve.
If your requirements are purely internal and you do not need to do any joining or splicing then I would thoroughly recommend the AMP Lightcrimp Plus method.
You can buy the kits from specialist suppliers (pm me if you want me to recommend somewhere).
These cost about Â£800 (remember to buy plenty of spare connectors)
Once mastered, and I will emphasise this as each end is Â£5 min and whilst you are learning how to do it the failure rate is as high as 80%, termination is as easy as fitting an RJ45 plug and meets all of the current regulations.
You will need at least a visible laser test set @ about Â£120 and an assortment of different patch cables to connect to the various switches/modules that are out there.
If you need to certify your work you will need to invest in something like a Fluke Certifibre which will set you back another Â£3k (tip: Fly to the states for the weekend, buy it there and bring it back it's half the UK price)
So as you can see, to set yourself up for a bit of DIY Fibre installation could cost you Â£4.5 - Â£5k but once mastered you can sell your newly found skill to other fibre needy geekers!
All other methods require specialist tools, equipment and training and unless your working for a company that can recoup the investment needed it is unlikely that you could justify the costs.
So, Litecrimp is probably your only choice and a 20 min how to video is included in the kit.
should I be asking him to install more/better cables while he's at it?
It costs a lot more (8 core is generally 1.5 x the cost of 4) but if you need to boost bandwidth this is the only way to do it.
And don't for get to have a nylon pull through left in your underground ducts so that you can tug a new one through when you need it.
Only 50/125 Cable will give you more than 220m with SX modules.
If you go over 550m you will need LX modules.
Only OM3 Fibre is rated for 10GBe if you think you will ever go there.
Sure, you can tag your VLans but if you shove them up the same pipe you still have a log jam. So LAG your links and enjoy a boost in performance.
If you want to move twice as much traffic between point A and point B use two lanes!
The 80k figure mentioned in the earlier post included at the time, the fibre cabling and 10GBe from core to edge.
So by "Typical" this is really what I would be expecting any new build's to be specifying.
Am I asking the contractor to install one strand of 50/125 fibre cable, or should I be asking him to install more/better cables while he's at it?
I would - the cost of putting more in there at the start will be significantly less than the cost of adding more in two years.
Originally Posted by dhicks
RADIUS authetication - do I actually need this? My plan was to simply let any computer that wanted to connect to our network and concentrate on making sure each individual server was secure.
Whatever you mean by "making each server secure" it won't protect you against people plugging their own virus-infected hacking-tool-equipped laptops to the network. If I had the money for it, full RADIUS would be a must for me.