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Four Simultaneous Access Points OK for 802.11b
jlouderb writes "ExtremeTech is reporting on a new analysis that shows that four of the 11 802.11b channels can actually be used simultaneously, rather than the just the three used today. This has big ramifications for multi-access point installations, especially in taller buildings. The analysis was done by the CTO of an 802.11b startup called Cirond and a white paper with all the details should be posted to their site later today."
The general map coloring problem is pretty useless in a 3D world, there is no minimum # of colors, for example. Buildings, however, are not 3D, they're layers of 2D, so it would be solving a modified 2D map coloring problem.
Erik
YOU ARE SAYING IMPUDENCE TO ME! THAT IS IMPUDENCE!
Essentially, they are being "risky". A small section of overlap, in the weaker power section. I'm sure that they are not the only people to think of this. Certainly, they use of four aps does help cover an area more effectively, no question, and the diagrams do help show that :)
-- Who is the bigger fool? The fool or the fool who follows him? --
Nothing annoys me more than the overly-precise. Let me take this point-by-point:
Yer right about the method by which the author asserts that the extra channel is made possible by addition of the third dimension (or third floor, in the least-case solution of his problem). But then you go and blow it with hyper-precision. Honestly, in this day and age, your "site survey" will very likely consist of a tech wandering around with a laptop looking at the signal meter. If the company in question is particularly anal, that tech might be actually carrying a notepad and perhaps an actual signal strength meter. Numerical modeling? Not likely.
Your second paragraph is predicated on the idea that the lan will consist solely of wireless. Again, not likely: not many people want to bother with replacing existing ethernet cards sitewide with 802.11 cards. More often, the wireless is for new computers and for laptop users, which is really a small proportion of all the computers in the building, no? As for myself, I have a wireless link in my office, which is fine for all sorts of "real work," and if for some reason I need to move big chunks of data, then and only then will I bother grabbing a 100-base-T link.
As to your third paragraph, utter hogwash. We have been very successfully setting up reasonably-sized labs with wireless-only networking for some time. It's really nice to do this when buying new hardware - what a dream when the only cable you need is power! (big hint here: try to find a cheap - US$750 with air, er, 802.11 built-in - computer, with a unix installed, and no butt-full of spaghetti sticking out the back. Give up? Think different) No problems. None.
"It's people like you what cause unrest"
political_news.c: warning: comparison is always true due to limited range of data type
One thing they are forgetting in all this "excitement" is that it does matter a great deal the distance between the four different channels. It matters how close you have those APs together. If they are right next to each other, they will probably overlap their signals by as much as 50% or so. (Although software takes care of this.)