I'd love to use 5g radios but that's not going to happen. I've considered preaching the 11a gospel to the other institution on the chance they might convert ;+)
...thanks for the response........J On Thu, 13 Nov 2003, John J. Brassil wrote: > It works OK - our engineering school recently completed a new wing that has > a large central atrium similar to the one you describe. This is an > extremely dense environment for RF - 84 APs for this single wing! They > wanted as much throughput as possible, so our contractor designed a > picocell network with as many as 3 APs in a single room, one on 1, one on 6 > and one on 11, dialed to 1mW and in some cases futher attenuated with > inline 10 and 25 dB resistors (I know resistors aren't measured in dB but > that's the net effect of the attenuation.) > > Unfortuanely, depspite their best efforts, there is still a lot of leakage > outside the intended coverage areas - not a lot of signal strength, but > single- and low double-digit signal strength from non-primary APs in lots > of areas, the worst of which is the atrium which has at least 5 devices > visible to Netstumbler or AirMagnet in most places on all three channels! > > We haven't benchmarked the throughput rates but I would imagine they are > not full rate (we fix our APs at 11mbps) but my laptop at least has been > able to hold a connection in there every time I have tried. Others' MMV. > > The good news is that it all still works. For the situation you are > describing, I wouldn't screw around with 4 channels, that's just a hack > since the frequencies are what they are and playing games with 1 5 9 & 11 > or some other such silliness doesn't change that. Keep your same channel > APs as far apart as possible and do the best you can. > > Or buy some 5MHz radios and do it properly. :) > > John > > John J. Brassil | Network Engineer, Vanderbilt Data/Video Engineering > voice 615.322.2496 | ICQ 9660375 > > --On Thursday, November 13, 2003 3:33 PM -0500 James Savage > <[EMAIL PROTECTED]> wrote: > > > Hi, > > We're sharing a building with another institution and must also share > > the airspace. We've agreed to go to the four non-overlapping channel > > model instead of three. Each institution will use two channels. This is > > my first shot at full building coverage and foresee channel interference > > issues as I'm restricted to two instead of three channels. Presumably, > > this can be addressed with directional antennas and adjustment of signal > > strength but I thought I might ask more experienced folks who might have > > already experimented with channel interference. If two APs operating on > > the same channel can 'hear' each other, is it simply a throughput hit or > > do things just not work at all? Presumably, there's a relationship to > > how close the APs are to each other (signal strength-wise)...'closer' > > means more interference? Also, the amount of traffic is a factor as > > well? This particular building has a central open area surrounded by > > offices/classrooms with glass windows overlooking the open space. The > > signal seems to easily penetrate the glass and cover the open space as > > well.....ie....I have multiple APs operating on the same channel bleeding > > into the open space. Is this a show-stopper for the open space or is it > > possibly a slow but liveable scenario? > > > > ....advice or comments are greatly appreciated. > > > > ......thanks in advance.........Jamie > > > > James Savage York University > > Senior Com. Tech. 108 Steacie Bldg. > > [EMAIL PROTECTED] 4700 Keele Street > > phone: 416-736-2100 ext.22605 Toronto, Ontario > > fax: 416-736-5701 M3J 1P3, CANADA > > /\ /\ /\ /\ > > / \ / \ / \ / \ > > \ / \ / \ / > > \/ \/ \/ > > > > ********** > > Participation and subscription information for this EDUCAUSE Constituent > > Group discussion list can be found at http://www.educause.edu/cg/. > > > > > > ********** > Participation and subscription information for this EDUCAUSE Constituent Group > discussion list can be found at http://www.educause.edu/cg/. > James Savage York University Senior Com. Tech. 108 Steacie Bldg. [EMAIL PROTECTED] 4700 Keele Street phone: 416-736-2100 ext.22605 Toronto, Ontario fax: 416-736-5701 M3J 1P3, CANADA /\ /\ /\ /\ / \ / \ / \ / \ \ / \ / \ / \/ \/ \/ ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/cg/.
