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[oc] 802.11b and HiperLAN/2

Folks,

I'm not on this list (I am on too many, really, promise) but a friend
pointed me at this discussion and I wanted to add some comments and
pointers.

I want to vote in favor of the creation of an OpenCore 802.11b
implementation.  I am aware of three or four chipsets for 802.11b:
Intersil's Prism series, Lucent (Avaya? Agere?), and TI come to mind
off-hand.

The problem with all of these is that they do not publish the API for Access
Point mode.  An OpenCore implementation would give Open Source Software folk
a chance at creating real Access Points.  Doing this today requires paying
one of the above companies a license fee and agreeing not to release the
information to anyone else.  Not good for Open Source.

Some further info:

> > I have to admit that i have no idea of US official plans for such
> > systems. Usually these machines do not work in both places. Think of a
> > PCI cell phone for instance (900/1800 in europe, 1900 in us). what
> > seems to be though is that mentioned ieee WLAN standard is allocated
> > in european radio frequencies.
> > ieee standard seems to be quite a bit more specifically one use system.
>
> > Could someone check US regulations and possible plans etc?
>                                                                           > I think IEEE 802.16 has plans for the 5GHz Frequency. See
>
> http://ieee802.org/16
>
> If you have a URL to the hyperlan standard on the ETSI site, I would be
> interested in that.  When I do a search on Hyperlan, nothing comes up.

First:  The European effort, which came out of earlier work by the ETSI, is
called "HiPerLAN/2".  It stands for "High Performance (wireless) LAN".  You
can find them at http://www.hiperlan2.com/

Second: The US ISM (Industrial, Scientific, Medial) bands, which are
unlicensed, are very close to bands in Europe and Japan that are reserved
for the same purpose.  This was done so that products *could* be the same in
all three zones.

In the US, the 2.4GHz range is only slightly smaller than the European
range.  802.11b wireless devices in the US can be set to use any of 11
channels, while Europe gets 13, I believe.  Note, however, that Direct
Sequence Spread Spectrum uses wider bands than Frequency Hopping, so as a
matter of practicality folks typically use channels 1, 6, and 11 in the US.

The 802.11 committee has a number of different specifications out.  The
original 802.11 specification only ran to speeds of 2Mbps (though some
implementors 'cheated' to get 3 or 4Mbps speeds).  The 802.11b specification
uses different encoding and 5-channel-wide bands to get 11Mbps.  There is
another, I think it was 802.11g, that was working on doubling the rate to
get 22Mbps.

All of the above are within the ISM band at 2.4GHz, and work equally well,
if not better, in Europe.  The Lucent/Orinoco/Avaya/Agere/WaveLAN--whatever
name they are this week--cards all support 802.11b in the 2.4GHz band.

The higher range, the 5GHz band range, is also compatible (mostly) between
the EU, the US, and Japan.  In the US, where a preference for IP has been
mandated by the corporate gods, it looks as though IEEE 802.1a is the
designated winner in the 5GHz race.  Europe is a bit more free (go EU!) and
are still allowed to utter the ATM acronym.  HiperLAN/2 is cool because it
can carry IP, PPP, Ethernet, Firewire, and/or ATM cells.  At least, that's
what is planned.  Personally, I think that *real* QoS is a Very Good Thing
when dealing with a limited bandwidth medium such as wireless.

BTW, 802.16 is a Metro-Area Network technology, while the 802.11 family is
aimed at Local Area Networks.

Anyway, send me mail directly if you'd like any more pointers.

Chris -)-----

See:
  http://www.hiperlan2.com/
  http://www.intersil.com/design/prism/
  http://www.ti.com/sc/wirelessnetworking
  http://www.linux-wlan.com/  (good docs here...do some looking 'round)
  http://www.live.com/wireless/unix-base-station.html

The Apple Airport is a good, cheap way to start playing with wireless:
  http://www.apple.com/airport/
  http://freebase.sourceforge.net/
  http://edge.mcs.drexel.edu/GICL/people/sevy/airport/index.html

-- 
Samba Team -- http://www.samba.org/     -)-----   Christopher R. Hertel
jCIFS Team -- http://jcifs.samba.org/   -)-----   ubiqx development, uninq.
ubiqx Team -- http://www.ubiqx.org/     -)-----   crh@ubiqx.mn.org