1230 vs. 1240 (5Ghz) radios ?

rduke · ‎11-08-2007

Has anyone compared wireless performance of the 5 Ghz "a" radios in the 1230 vs. the 1240 series AP's. We have a bunch a 1230's and some don't work that well in our enviroment. I am wondering if the 1240's work better than the 1230's. I know the 1240's are newer, but I inherited 1230's where I work.

I would appreciate any comments on your experience between the two radios.

Randy

scottmac · ‎11-08-2007

Your question is a little fuzzy, but I believe it boils down to a 5G versus 2.4 G kinda question.

With maybe a few exceptions, the 5G radios (802.11a) will generally offer better performance (with caveats) for the following reason (and I'm sure there are more):

802.11a had 40 non-overlapping channels versus the three on 802.11g. You can have more APs in a given area without re-using channels.

It is "less popular" so there are fewer clients using those 40 non-overlapping channels.

5G tends to have a slightly more energetic bounce (it is more attenuated from water / moisture), it doesn't penetrate much, if at all (byt 2.4G is not much better)

You can get more gain in the same space as a 2.4G antenna. However, you need more gain (generally speaking) because the 5G signals tend to not travel as far.

There are fewer things using that spectrum, so there is, generally speaking, less interference at 5G. Remember that Bluetooth is "full spectrum noise" for 802.11G.

From a practical standpoint, the biggest selling point is the 40 channels. You can argue that it's more secure since "hackers" will go for the biggest chance of penetration (read that as "The most stupid people with unsecured / poorly secured APs or ad-hocs") , which would be in the 2.4G arena.

I you can make it fit without too much pain (financial or otherwise), 802.11a is probably a better coverage solition.

(All of this relies on doing a proper site survey to verify the fit)

Good Luck

Scott

rduke · ‎11-12-2007

Scott,

Thanks for the reply. I was trying to avoid making the post too long so perhaps the question did not make sense. I was wondering about the difference in radio quality between the 1230 and 1240 APs on the A radio only. We are not using the G radios except to listen for rogues. The only problem is that the 1230 A radios are not performing that well in some of our locations which are metal buildings. (multipath more than likely). I am looking in to whether or not the 1240s would be better. I suppose I would not see much difference. I may just get a 1250 for testing purposes. Suposedly the MIMO radio would work better with existing clients. The only bad thing is that they run on 56 volts so I can't use my existing PoE equipment.

Randy

scottmac · ‎11-12-2007

I believe the radios are the same (other than maybe a newer version of the same radio) ... something like an RM-21A.

I don't think you'll see any significant difference between the 1230 and 1240. Pretty much the same radios, same antennas.

I haven't played much with 802.11n/1250, but the literature suggests that your assumptions are correct. Hopefully someone else can offer some solid direction on that for you.

Good Luck

Scott