b or g for best distance?

I'm setting up a wireless network in a two story brick house.
Speed is not a major concern as the network will be used mainly for sharing
a dsl internet connection and not file sharing between the 4 computers.
Would wireless "b" or "g" be the best option for maximizing distance and
penetration through brick walls?

On Sun, 11 Apr 2004 13:19:47 +0800, "John" <(E-Mail Removed)> wrote:

>Would wireless "b" or "g" be the best option for maximizing distance and
>penetration through brick walls?

they are the same from a radio perspective and g falls back to b
standards at weak signal levels (long distances)

Phil

In article <(E-Mail Removed)>,
Phil Thompson <(E-Mail Removed)> wrote:
:On Sun, 11 Apr 2004 13:19:47 +0800, "John" <(E-Mail Removed)> wrote:

:>Would wireless "b" or "g" be the best option for maximizing distance and
:>penetration through brick walls?

:they are the same from a radio perspective

They are NOT the same from a radio perspective: they use different
waveform encodings that have different properties when they encounter
situations that would lead to multipath.

http://www.commsdesign.com/story/OEG20030114S0008

: and g falls back to b
:standards at weak signal levels (long distances)

That's not correct. If you look at the symbol rate specs of
combined 11b / 11g products (such as a Cisco AP1200), you will see
that they have different symbol rates at long distances. Notice for example
in the chart at http://www.54g.org/standards.html that 11g can use
the symbol rates of 9 and 6 Mbps


Atheros has an interesting White Paper about range. It's a bit old
now, but the answer isn't straight-forward.

http://www.atheros.com/pt/atheros_range_whitepaper.pdf

But check out also the commsdesign link above -- it disagrees on
some tests with the atheros one.
--
Whose posting was this .signature Google'd from?

Right. 802.11g falls back (eventually) through 12, 9, then 6 Mbps. 802.11b
uses a completely different encoding scheme, and the bitrate sequence 11,
5.5, 2 and 1 Mbps.

Some confusion arises because people hear that the 802.11g standard
includes, and requires support for, the 802.11b standard. This is correct,
but it refers to the fact that an 802.11g AP is required to support
connection of 802.11b clients using 802.11b encoding methods. 802.11g
clients are required to support "safety" measures in the presence of 802.11b
clients, to allow the 802.11b stations to detect transmit attempts by
802.11g stations.

This can lead to the incorrect conclusion that 802.11g is required to
devolve into 802.11b if the signal strength is too low. As far as I can
tell, this behavior is not required, but it might be permitted. For example,
I imagine it's okay for a client driver to give up trying to associate under
the 802.11g regime, and retry under 802.11b. Something like that would
probably be a configuration choice, and the criteria for when to do this
would not be addressed by the standards.

"Walter Roberson" <(E-Mail Removed)> wrote in message
news:c5c424$7nl$(E-Mail Removed)...
> In article <(E-Mail Removed)>,
> Phil Thompson <(E-Mail Removed)> wrote:
> :On Sun, 11 Apr 2004 13:19:47 +0800, "John" <(E-Mail Removed)> wrote:
>
> :>Would wireless "b" or "g" be the best option for maximizing distance and
> :>penetration through brick walls?
>
> :they are the same from a radio perspective
>
> They are NOT the same from a radio perspective: they use different
> waveform encodings that have different properties when they encounter
> situations that would lead to multipath.
>
> http://www.commsdesign.com/story/OEG20030114S0008
>
> : and g falls back to b
> :standards at weak signal levels (long distances)
>
> That's not correct. If you look at the symbol rate specs of
> combined 11b / 11g products (such as a Cisco AP1200), you will see
> that they have different symbol rates at long distances. Notice for
example
> in the chart at http://www.54g.org/standards.html that 11g can use
> the symbol rates of 9 and 6 Mbps
>
>
> Atheros has an interesting White Paper about range. It's a bit old
> now, but the answer isn't straight-forward.
>
> http://www.atheros.com/pt/atheros_range_whitepaper.pdf
>
> But check out also the commsdesign link above -- it disagrees on
> some tests with the atheros one.
> --
> Whose posting was this .signature Google'd from?

802.11b would be your best choice for those conditions.

Bill Crocker

"John" <(E-Mail Removed)> wrote in message news:4078d53a$(E-Mail Removed)...
> I'm setting up a wireless network in a two story brick house.
> Speed is not a major concern as the network will be used mainly for
sharing
> a dsl internet connection and not file sharing between the 4 computers.
> Would wireless "b" or "g" be the best option for maximizing distance and
> penetration through brick walls?
>
>

On 11 Apr 2004 18:50:44 GMT, (E-Mail Removed) (Walter
Roberson) wrote:

>That's not correct. If you look at the symbol rate specs of
>combined 11b / 11g products (such as a Cisco AP1200), you will see
>that they have different symbol rates at long distances.

actually I had looked at the specs of a b/g card and noted that as the
signal strength diminished the speed and encoding was the same.

Looking at the AP1200 I see the sensitivity speed is the same for b
and g at -89 dBm = 5.5 Mbps, -91 dBm = 2 Mbps both b and g using DSSS
so at the limit of range g is the same as b

My comment about the radio side being the same refers to signal power
and frequency, which ultimately detemrine range. Fancy coding may
improve bit rates at a given signal strength, or improve resilience to
multipath or other inerference.

The commsdesign paper compares a and g, didn't gain much on b vs g

>11g can use the symbol rates of 9 and 6 Mbps

then falls back to using 5.5 Mbps and the same rates and encoding as
802.11b


Phil

On Sun, 11 Apr 2004 19:32:40 GMT, "gary" <(E-Mail Removed)>
wrote:

>Right. 802.11g falls back (eventually) through 12, 9, then 6 Mbps. 802.11b
>uses a completely different encoding scheme, and the bitrate sequence 11,
>5.5, 2 and 1 Mbps.

g includes this latter encoding scheme and drops back to it once the
signal is too weak for 6 Mbps. The spec sheets I have read for 802.11g
devices all quote the same encoding and sensitivity at the ragged edge
as they quote for b, as g uses OFDM then drops back to DSSS

Phil

John <(E-Mail Removed)> wrote:

> I'm setting up a wireless network in a two story brick house.

You should consider HomePlug's. No problems with wall/floors/ceilings.
--
Groeten,

Antonio (Voor email, verwijder X)

> You should consider HomePlug's. No problems with wall/floors/ceilings.

I've tried various HomePlugs and they did not work well in my home. I gave
them all away. YMMV.

Best,
Christopher

In article <(E-Mail Removed)>, "Christopher Glaeser" <(E-Mail Removed)> wrote:
>> You should consider HomePlug's. No problems with wall/floors/ceilings.
>
>I've tried various HomePlugs and they did not work well in my home. I gave
>them all away. YMMV.


Really?? You had better results in a Brick (not stick) built home with
wireless?

>
>Best,
>Christopher
>
>