roaming nodes -was- Re: [MLB-WIRELESS] [TECH] Dipole antennas, and melbwireless

Clae clae13 at yahoo.com
Wed Mar 20 01:30:07 EST 2002


BTW I've added a proposed workgroup to the wiki, called "WGRoamingNodes"
http://www.wireless.org.au/wiki/?WorkingGroups

>At 07:25 PM 19/03/2002 +1100, Ben Anderson wrote:
>
>>I think it's do-able, just not trivial :)  It should work, just with minor
>>interruption - this isn't a major concern to me, the scalability issues are
>>much more interesting...
>
>I might wanna run tram mobile on a Windows box LOL  (ppl who know me 
>would believe this :) ).

I believe this :-)

It occurs to me there are two slightly different appraches here:  the 
truly mobile, ubiquitous, always-on, auto-roaming, 100kph down the 
western ring-road approach, and the node that might relocate once or 
twice a day - the laptop user who heads off to the park or cafe for 
example.  And thus two somewhat different levels of doability.

QoS in the case of the occasional roamer could be a lot lower - a few 
minutes to  sign on might be acceptable, as opposed to instantaneous 
handover.  And blanket coverage might not be essential either - one 
cafe or park bench might have better connections than another, and as 
long as the coffee/scenery was up to scratch, that might be okay.

Is the latter case in fact qualitatively different from a stationary 
node?  Because it's this version of "roaming" that most interests me.

>>  > We must support tunneling, as it is the most feasible way to rapidly link
>>>  segments right now, until more wireless links take over.
>>
>>Yep, shortcutting the mesh is going to be *very* important to the overall
>>scalability of the network.

won't the directional links serve this purpose to some extent?

>And these routes can be statically specified.
>
>>Yes, though being able to limit the zone of this discovery to a couple of
>>hops, and not the entire network, is going to be an absolutly massive
>>advantage in scaling this to large networks.

I can see here where "relocating" nodes differ from truly stationary 
ones.  I might only want to move a few times a week, but i might want 
to move from one side of the city to the other.

>>The lat/long thing should _work_ -- it might not be optimal, but it should
>>guarantee a reasonable method exists...  Plus, because the network is
>>effectilvy source routed, with broadcast auto source-route discovery, there
>>could be an interface for the originating station to define more optimal
>>routes...  For example, static-shortcut lists could be propegated to all
>>nodes on a daily, or weekly basis for example without being a significant
>>overhead -- and that way the originating node could calculate how to most
>>effectilvy use the shortcuts to mimise the mojo cost for a particular
>>connection, or minimise the latency regardless the cost of mojo -- that
>>decisoion is a 'originating stations' choice...

one day i will understand paragraphs like that really i will
right now it just makes my head hurt :-)

Is any of this covered by what these guys are doing?
http://www.meshnetworks.com/

"MeshLAN software transforms wireless LAN cards into 
router-repeaters, which enhances and extends the wireless reach of 
each subscriber in the network. A MeshLAN-enabled Wi-Fi user who is 
out of range of an access point can hop through one or more users to 
reach the access point. Furthermore, the MeshLAN routing intelligence 
will automatically shift transmissions from congested access points 
to uncongested ones - easing bottlenecks and improving overall 
network performance."

I seem to remember they were licensing their software free for 
non-commercial applications, but that might have been someone else 
with a similar name.

>Hrm, maybe...  Dunno, I'm not a lawyer. :)

neither am i:  here's the bit that makes me wonder though:
from http://www.itee.uq.edu.au/~mesh/doc/2001-10-25-aca-answer.txt

Section 34 (1) provides that a base station is part of a
terrestrial radiocommunications customer access network if the
following tests are met.

///
(f) the network does not have inter-cell hand-over functions;
///
The facility or facilities that will use the 2.4GHz spectrum
to connect members of the cooperative to the network does not
have inter cell hand over and therefore meets the terms of
section 34 (1)(e).
[I presume he means 34(1)(f) - David]

///except (our old friend) ///
Certain exemptions are also established in section 34(2) ... if the
network is used, or in use, for the sole purpose of supplying
carriage services on a non-commercial basis.


>
>73 de Tony, VK3JED
>http://vk3jed.vk.irlp.net


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