connectivity solution

[dezt]

Can someone recomend me a system to connect 2 blocks to our main building. At a guess I would say that the distance between the server room and the switches in both buildings is over 100m, so I either have 1Gb fibre or radio link to use. I was looking at getting quotes for fibre, but the SBM has asked if we can use radio links because she doesn't like cables every where.

My main questions are, what is the speed I would be able to get out of a radio link? would it be 1Gb or am I hoping for too much?

And most importantly, which would be the cheapest option? Which is most reliable?

[Joanne]

you can buy lasers...

we have a 100mb one, but you can get gig ones now... takes a bit of aligning and as long as you can see one building from the other seem to do the job.

We have one... did work once, but because nobody has used it in the last 2 years we have failed to see when it broke.

[Ric_]

It depends on what you have in the remote blocks... a couple of PCs would not warrant a laser link but radio would not provide sufficient bandwidth unless you went for microwave - which is costly again.

Ideally, you want fibre though because it is more cost effective in the long run - taking into account maintenance on external equipment and time realigning lasers/antennae after you kids boot a football at it!

[Gerry]

I wouldn't use wi-fi to connect switches in various buildings. Fastest wi-fi is a theoretical 108Mb/s I believe. Transmission rate decreases with range and other factors such as trees and walls. 2.4Ghz frequency that wi-fi uses is severely affected by water. You'd have to use directional antennas too and some special routers to increase security and transmission range. It's possible to use a 5.4Ghz frequency (20x better water penetration) but that depends on getting a licence from Ofcom. Antenna's also make a good target - for kids and for lightning.

I would recommend fibre as it's faster and more reliable. It will also allow for future expansion. It may cost more than wi-fi solution, but it's the best way to go. And tell your SBM that you don't just leave fibre cables lying around - repairing a cable is extremely expensive and sometimes cheaper to just replace it if it's not too long - so most places will bury it or use an existing conduit. We use fibre between all our networked buildings.

Try these sites for more info on wi-fi if you want:
http://www.binarywolf.com/249/wifi_basics.htm
http://www.solwise.co.uk/los.htm

I've looked at lasers too, but they're extremely expensive:
http://www.cablemanstore.co.uk/erol.html
take a look at the GeoDesy stuff...

[TronXP]

Fibre all they way, if you dont want to see the cable, dig a trench and hide them... costs more than flying but then she won't see the cable

[torledo]

I wouldn't use wi-fi to connect switches in various buildings. Fastest wi-fi is a theoretical 108Mb/s I believe. Transmission rate decreases with range and other factors such as trees and walls. 2.4Ghz frequency that wi-fi uses is severely affected by water. You'd have to use directional antennas too and some special routers to increase security and transmission range. It's possible to use a 5.4Ghz frequency (20x better water penetration) but that depends on getting a licence from Ofcom. Antenna's also make a good target - for kids and for lightning.

I would recommend fibre as it's faster and more reliable. It will also allow for future expansion. It may cost more than wi-fi solution, but it's the best way to go. And tell your SBM that you don't just leave fibre cables lying around - repairing a cable is extremely expensive and sometimes cheaper to just replace it if it's not too long - so most places will bury it or use an existing conduit. We use fibre between all our networked buildings.

Try these sites for more info on wi-fi if you want:
http://www.binarywolf.com/249/wifi_basics.htm
http://www.solwise.co.uk/los.htm

I've looked at lasers too, but they're extremely expensive:
http://www.cablemanstore.co.uk/erol.html
take a look at the GeoDesy stuff...

i think it would be really good to have a section in the wiki on ptp/ptmp wireless connectivity options as they've been a couple of queries recently about connectnig disparate buildings....plus there's a lot of confusion, well in my head atleast.

I hear about 4.9, 5.4 and 5.8 ghz frequenzies mentioned for outdoor RF options but what's the difference between these and the various 802.11a bands, and are 5.4 and 5.8 not in unlicensed spectrum ? Where is the best source of information at what frequencies are available for a particular usage.

[dezt]

Thanks for the info guys, looks like it's fibre (which is what I was hoping for anyway).