802.11g and 802.11b in an ad-hoc network

If I were to set up an ad-hoc network of 3 computers, 2 with wireless
G and 1 with wireless B, would the 2 computers with wireless G be able
to communicate with each other at 54 Mbps, or would the whole network
be slowed down to wireless B speed when the Wireless B computer was
present?

I'm not an expert on this, but it is my understanding that any 802.11b
devices accessing 802.11g/b devices in a mixed mode (on the same channel)
will force ALL devices to communicate at 802.11b speeds.

"David Simcha" <(E-Mail Removed)> wrote in message...
> If I were to set up an ad-hoc network of 3 computers, 2 with wireless
> G and 1 with wireless B, would the 2 computers with wireless G be able
> to communicate with each other at 54 Mbps, or would the whole network
> be slowed down to wireless B speed when the Wireless B computer was
> present?

"Bill Jasiulewicz" <(E-Mail Removed)> wrote in message
news:0Txnd.18967$(E-Mail Removed).. .
> I'm not an expert on this, but it is my understanding that any 802.11b
> devices accessing 802.11g/b devices in a mixed mode (on the same channel)
> will force ALL devices to communicate at 802.11b speeds.

Close, but not exactly. The "b" stations are approximately 5 times slower
than the "g" stations. If any "b" station is constantly streaming data, it
will hog the available bandwidth. For every unit of time "g" data is being
transmitted, there are 5 units of time in which the "b" data is being
transmitted (roughly speaking). The "g" device may be sending at 54 Mbps
when it has the chance, but it doesn't have that chance very often. The net
effect is to drag the overall throughput down to the range of 11 Mbps. It
only takes a few legacy devices to have this effect.

Even if the "b" stations are mostly idle, the "g" stations precede every
data tranmission with a CTS message at a "b" bitrate to warn the legacy
stations to stay off the air (these stations cannot detect "g" signals).
These protection messages slow throughput even if the "b" stations aren't
doing anything.

If you want details, see:

http://www.commsdesign.com/printable...cleID=16501220

>
> "David Simcha" <(E-Mail Removed)> wrote in message...
>> If I were to set up an ad-hoc network of 3 computers, 2 with wireless
>> G and 1 with wireless B, would the 2 computers with wireless G be able
>> to communicate with each other at 54 Mbps, or would the whole network
>> be slowed down to wireless B speed when the Wireless B computer was
>> present?
>
>

On Sat, 20 Nov 2004 02:21:48 GMT, in alt.internet.wireless , "Bill
Jasiulewicz" <(E-Mail Removed)> wrote:

>I'm not an expert on this, but it is my understanding that any 802.11b
>devices accessing 802.11g/b devices in a mixed mode (on the same channel)
>will force ALL devices to communicate at 802.11b speeds.

I believe this was true for older routers, but is not so any more.

--
Mark McIntyre
CLC FAQ <http://www.eskimo.com/~scs/C-faq/top.html>
CLC readme: <http://www.ungerhu.com/jxh/clc.welcome.txt>

I`ve asked a very similar question to this as I`ve been told the max speed
an Ad-hoc setup can work is 11.Mbps even if you use `g` gear - something to
do with when the standard was setup.

--
Andy M Moore
(E-Mail Removed)

(E-Mail Removed) wrote:
> I`ve asked a very similar question to this as I`ve been told the max
> speed an Ad-hoc setup can work is 11.Mbps even if you use `g` gear -
> something to do with when the standard was setup.

Nope, see other post. Used to have a b and g, was 11 then, got a new card to
replace the b, and now it's 54.

well of course, it stands to reason if you have 2 cards and 1 is a B then
the fastest speed you will get is 11Mbs. Your Network is only as fast as its
slowest part.

If you Ad-Hoc 2 G cards then your speed will be 54Mbs baring distance
variables and bad equipment of course.


"Peter Pan" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> (E-Mail Removed) wrote:
>> I`ve asked a very similar question to this as I`ve been told the max
>> speed an Ad-hoc setup can work is 11.Mbps even if you use `g` gear -
>> something to do with when the standard was setup.
>
> Nope, see other post. Used to have a b and g, was 11 then, got a new card
> to replace the b, and now it's 54.
>