Wednesday, 16 April 2014

Wireless - Quick update (part 3)

We have lots of wireless work going on here as part of a project to cover the whole campus. The first two parts of the post can be found here (Part 1) and here (Part 2).

A few decisions have been made and, despite a number of meetings on the subject, many still unfortunately haven't. The stalling is mostly to do with ways to do high-density and high-usage. I have been pushing to use directional antennas and 'massaging' the data rates (and getting rid of 802.11b), but for whatever reason the 'higher-ups' are still holding off.

What has been pushed forward is that we have ordered two more WiSM2 controllers, on which we are going to install software version 7.6 MR2 and provide service to 3702 access points, that have now started to arrive. We have another 2000 access point licences too. However, having different controller software versions running is going to have to have some thinking about, so that users are not roaming across controllers and experiencing problems as a result.

We are planning to go ahead and look at dual-band antenna solutions for the 3702e to be deployed in high-density, high-use areas such lecture theatres, conference rooms and seminar rooms.

We have 7 more buildings fully covered and we have deployed around 70 access points with another 94 waiting for contractors to install.

We have been doing some RRM (radio resource management) testing. Some decisions looked strange that were made by Cisco RRM, but we don't really have the tools, such as a spectrum analyzer, to challenge it. So we've been stuck with testing throughput/loss/retries, changing it to what we think the channel and power selections should be and comparing the results.

We have found a few rogue networks on our surveys and also an area of campus where they will be using multiple AR drones (up to 8 at a time), which are controlled over the 2.4GHz frequency. Getting very tempted to almost 'force' 5GHz.

We spoke to our suppliers last Thursday who recommended we install two cables to each AP, a cat5e and a cat6, for wave 2 of 802.11ac. Needless to say, that didn't go down well with management.  The meeting was called to discuss some new buildings that are being built and how we will cover them with wireless. The suppliers though came up with the same argument as those of us doing the surveys 'in house'; you can't say where the wireless should be without testing and you can't test before the building has been built. However, the builders want the locations marked on the plans BEFORE the building starts going up. So it is a bit of a vicious circle... that usually ends up as a lot of guess work and crossing of fingers.

I think it was hoped that they would be able to use their experience to provide a better 'educated guess'. They were understandably reluctant to say they could make recommendations that would work, but I think they are going to make some suggestions once they've got the latest building diagrams.

...and in other wireless news:

Quantenna Communications have announced the first 10G Wi-Fi using 8x8 MIMO.

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