Questions[interference](server)

I have an AP that serves both 2.4 and 5 GHz networks (on separate SSIDs, without fallback). The neighborhood is quite busy (residential neighborhood)

A ping from a wired device to a device on the 2.4 GHz network looks like this (the x axis is time, y is RTT in ms):

The equivalent ping on the 5 GHz network is much more stable ("flat").

While I understand that heavily loaded channels lead to worse performance, I am very curious about the regular nature of the graph.

I gathered a larger sample and can run it through a Fourier transform to get the frequencies (but I doubt that this would be of help?)

I have a gigabit switch and I am connecting my laptop to it using a cat6 ethernet cable.

The problem is it is connecting to 100Mbps only instead of 1Gbps.

This is what i found :

1. The is a zone in which the cat 6 cable passes where there are electrical connections and wires... at some point the cat 6 cable crosses an electrical wire
2. I tried to remove the cat 6 cable from this zone where there are electrical wires ... when I do this my laptop connects at 1Gbps
3. So I am pretty much sure there are some kind of interference with the electrical wires
4. I have tried to make the cat 6 cable cross the electric wire perpendicularly instead of parallel to it... this does not work .. I stil get 100Mbps

I am obliged to pass the cat 6 cable in this zone.. there is no other route... what are the solutions to this problem? How to avoid interference with the electrical wires??

There were a handful of mice bought before I got here and they've had bad issues with random clicks, movements, and pauses. They've also had some issues getting them synced. They're using 27MHz RF.

So, I could use Bluetooth, but there's already a preponderance of headsets running around. What are the chances we'll get interference with them?

Who has experience with this?

There are many pages on the web advising the use of wifi channels 1, 6 and 11 only, so that your wifi channels don't overlap.

Obviously this makes sense when you only have your network do deal with, but in most urban areas there are now a plethora of other networks, all using the same channels. In my current location there are about 4 networks on channel 6, and a couple on channel 1.

So my question is: What happens when you get lots of networks on the same channel? Do the intelligently share it? It is better to have two networks on channel 6, or one on channel 5 and one on channel 6?

How many bluetooth headsets can exist in a small space without there being interference or reliability issues?

We're about to switch our phone infrastructure to IP. New phones are on the way and we just realized 1) Headset support is expensive (Wired or Wireless), 2) The phones we HAVE TO get (for a completely different reason) supports bluetooth.

Seven or more people will have Bluetooth capability on their new phones (Nortel 1140E). Most are within 10 feet from each other ('next-to' cubicles in a semi-circle), and in the center we have an Aruba Access point (802.11a/b/g) serving clients within a 30-40' radius.

Has any of you had experience with this? Do you have good recommendation(s) for minimizing interference? Do you have an opinion on the best bluetooth headset to support this kind of setup?