Subject: Re: Stable Linux MANET Implementations?

From: Mary Baker <[email-masked]>
Date: Fri, 03 Mar 2000 17:26:29 -0800

> 
> I wrote to one member of the manet group on this issue, and his reply
> was
> >yes v6 for ad hoc nets will be interesting...when v6 happens of course.
> A reply that suggests v6 is a long way away. However, everyone said that
> about computers having 100 MB/ram (when the biggest you ever heard of was
> 8 MB). Given the current congestion of the numbering space in IPv4, and
> that IPv6 stacks do exist, a shift to v6 is imminent.
> 
> Comment, anyone?

Those interested in this topic might like to look at 
	http://www.dsg.stanford.edu/papers/triad/triad.html

This is a project called TRIAD going on in David Cheriton's group at Stanford,
and it addresses some of the worries people have about IPv6 deployability.
It even has a section in it about perceived deployability issues.  They
present what looks like an interesting alternative that is, in a sense, 
already
taking place.  Please note that I'm not a member of the TRIAD project, but
I found it to be interesting reading.
  
Mary

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From: Li Li <[email-masked]>
Date: Sat, 4 Mar 2000 01:12:22 -0500 (EST)

Lots of people I talked to do not really think there are convincing 
applications for ad-hoc routing except in the military. For example, in 
our dept., the wireless device uses the BS to communicate to the internet 
and to one another. Lots of places that the wireless device needs 
connection, there are infrastructures such as workplace, airport, hotel, 
etc. 

Can anyone make a case for convincing applications outside the military?

Li Li
Dept. of Computer Science
Cornell University

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From: "Andrew T. Campbell" <[email-masked]>
Date: Sat, 04 Mar 2000 02:01:51 -0800

POS

-- 
Andrew
http://comet.columbia.edu/~campbell

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From: Zygmunt Haas <[email-masked]>
Date: Sat, 4 Mar 2000 05:23:40 -0500 (EST)

Hi Li,

> connection, there are infrastructures such as workplace, airport, hotel, 

Hmmm, you may be talking to the wrong people (:-) ...

There are a number of applications of the ad hoc networking technology
outside the traditional military sector. The most notable, in my opinion,
are the sensor networks, such as, for example, would be needed for
communication in Smart Environments. There are, of course, many other
examples as well ...

Finally, the fact that in some cases there is an infrastructure, does not
preclude the use of a network that does not rely on the infrastructure, if
such use has some advantages ... For instance, use of ad hoc networks as
an extention to wireless LAN has been proposed ....

Zygmunt Haas.
==-=---===-===
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Prof. Zygmunt J. Haas                    tel: +1-607-255-3454
Wireless Networks Laboratory		                  
School of Electrical Engineering         fax: +1-607-255-9072 
Cornell University
323 Frank Rhodes Hall			 e-mail: [email-masked]
Ithaca, NY 14853			 
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From: Mark Thompson <[email-masked]>
Date: Sat, 4 Mar 2000 11:03:51 +0000

> Can anyone make a case for convincing applications outside the military?

``A boy-scouts meeting in a field?'' ;-)

Seriously though, there are numerous scenarios where full access to the
Internet (note the big I) is either not available or not necessrary. We're
in a world where it isn't just laptop computers that are comms enabled,
but also PDAs, cellulars, and toasters(!)  Whilst HomeRF, Bluetooth
etc. may be providing rudimentary comms for some of these scenarios,
they dont AFAIK cover the routing of messages via devices, only between
them, or via a designated hub/switch/router...

Granted, the often quoted scenarios of meetings in offices; the hotel
lobby even the dentists office (/me nods to the IETF ipngwg) usually
stress the "well, we can give you global addressing and stateless
addrconf, so you can access the 'net", but they all require supporting
infrastructure.

IMO, the strongest case for the manet initiative is that it is
striving to provide that infrastructure "for free" (i.e. no additional
switches/hubs/wLAN BSes/hardware), but by software stacks on the
participating clients themselves.

The "convincing applications" are every single networked device scenario,
but without the infrastructure hardware - just the devices (thus people)
that want to communicate.

... or am I way off the mark here?

Mark/

-- 
iam: networks and distributed systems
http://www.ecs.soton.ac.uk/~mkt/contact.shtml for contact info...

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From: Frederico Mesquita <[email-masked]>
Date: Sat, 4 Mar 2000 10:56:32 -0300 (EST)

??? POS ???

	What?

	[ ]'s

	fred
	DCC / UFMG

		"...uma coisa é conhecer o caminho,
			outra coisa é percorrê-lo..."

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From: "A. Bruce McDonald" <[email-masked]>
Date: Sat, 4 Mar 2000 13:06:31 -0500 (EST)

Hi,

In my opinion a MANET provides two very different potential network 
services: (1) It provides an instant---possibly temporary---network 
infrastucture where none is available; and (2) it provides an alternative 
network infrastructure in places where wireless/mobile access is 
available, but there is good reason for some group of users to bypass 
that infrastructure---perhaps 'sharing' access to that infrastructure.

What are the reasons for a group to bypass a network in favor of their 
own 'ad-hoc' network?  Cost, privacy, and ease of management come to mind 
for me.   If the communications needs are largely peer-to-peer, and the 
users are not in their home network, there is a strong argument NOT to 
use public wireless network services---both from a cost and security 
perspective, as well as from a performance perspective. Workers visting 
another company may not want their data available on the 'foreign' 
corporate LAN.  

Bruce McDonald
University of Pittsburgh

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From: "Jeff Monks" <[email-masked]>
Date: Sat, 4 Mar 2000 15:47:16 -0600

One example of a current vendor implementing static ad-hoc networks to
provide home Internet access is Rooftop Communications
http://www.rooftop.com/networkFRAME.html
recently acquired by Nokia.

Jeff

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From: "Charles E. Perkins" <[email-masked]>
Date: Sat, 04 Mar 2000 15:05:08 -0800

Hello Mary,

I also have read TRIAD, but I think there are some very significant
difficulties with the concept, which I don't want to go through just
now.  Suffice it to say that TRIAD deployment seems even more problematic
than IPv6 deployment, and that almost any scheme would work if everyone
agreed to do that scheme.  I don't think that TRIAD has any relevance
whatsoever to manet, and therefore I don't think this is the mailing
list to discuss the issues of TRIAD vs. IPv6.

Regards,
Charlie P.

---

From: Fabrizio Talucci <[email-masked]>
Date: Sat, 4 Mar 2000 22:03:29 -0800 (PST)

What about the space ?

Do we really need to create a full-duplex radio link from the earth to
each single satellite ?
One, or even more, huge, mobile and expensive antennas on the earth 
for each satellite to track ?

If only few of them, carefully designed and deployed (geostationary orbit?),
could take care of the communication-to-the-earth task,
the others would just need ...

a satellite ad-hoc network ?

less power, smaller antennas, smaller size, less weight, less money,
no more severe orbit communication constraints, ...

Just thinkering,

 Fabrizio Talucci
 CSD-UCLA

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From: Zygmunt Haas <[email-masked]>
Date: Sun, 5 Mar 2000 06:30:12 -0500 (EST)

> What about the space ?

Yes, and what about the inter-UFO communication. I can already imagine,
millions of spacemen roaming through the galaxy, creating ad-hoc
networks ... (:-) ...

---

From: Daniel Camara <[email-masked]>
Date: Sun, 5 Mar 2000 10:53:33 -0300 (EST)

Hi,
           
        Rescue scenarios, conferences, even iterative games, if you want a
more commercial, and funny, issue :).  Imagine a RPG played in an
iterative form, with portable devices and relative information about the
environment. Interesting no??  Can you imagine the complexity required in
the routing protocol to do this in a efficient way???

	It's only one more example :).

	 Regards...

---------------------------
Daniel Camara  (03/05/1999)
Computer Science Graduate Student
Department of Computer Science (DCC)
Federal University of Minas Gerais (UFMG) - Belo Horizonte - Brazil
http://www.dcc.ufmg.br/~danielc - [email-masked]

---

From: "Ron Orr" <[email-masked]>
Date: Sun, 05 Mar 2000 12:56:03 -0800

Sure,

Disaster Relief during earthquakes, floods, war, fires (forest and other)
etc. Government agencies when an an area is declared "disaster area".

Scientific expeditions.

News coverage for large events (Woodstocks?) in areas which do not have
adequate communications networks in place.

Military operations other than war, such as Bosnia, Kosovo, Solmalia, East
Timor, Sinai, etc

and others which do not immediately come to mind
-- 

> Date: Sat, 4 Mar 2000 01:12:22 -0500 (EST)
> To: [email-masked]

---

From: Carlo Kopp <[email-masked]>
Date: Mon, 06 Mar 2000 08:52:40 +1000

> and others which do not immediately come to mind

Ron, you might like to add general aviation (ie light aircraft) to that,
since there are costs associated with maintaining VHF radio coverage using
fixed repeaters, ad hoc allows for coverage beyond that, or coverage in
hilly areas where ground based VHF becomes too expensive.

Then we have the Third World and the aid distribution problem - in places 
were there is usually no useful infrastructure. We may only see the tip of
the iceberg on TV when there is a serious disaster or famine, ie there are a
lot of people doing this work in many places we don't see.

I am sure we can think of more applications with a little time.

I'd say the general case is any situation where many people and platforms
have to operate in areas where there is little or no fixed infrastructure.
Any scenario which fits that definition is a  potential or actual MANET
application scenario.

If people are arguing against the need for ad hoc outside of the military,
this may simply reflect the idea that if it is not a high traffic load
revenue service in a high density area, they think it is not a quick return
commercial proposal so they are not interested. This I think may be a little
short-sighted a position to take.

I have run into a number of people who have distinctly negative attitudes
to ad hoc, yet when I explored their motives I usually found other agendas
ie they thought it competed with one or another fixed networking scheme
they liked. 

The fixed insfrastructure network model is built upon a century or more of
cabled comms engineering, and more than a quarter century of satellite
centric comms engineering, most of which is built around assumptions of
almost static route behaviour. For a lot of people ad hoc opens up a
new frontier of route discovery algorithms and ideas, which many may find
a little intimidating. The behaviour I have observed seems to be centred
on the idea that it is easier to say that ad hoc is useless than actually
try to understand it !

I am convinced there is a huge number of potential ad hoc applications.

Cheers,

Carlo
-------------------------------------------------------------------------------
   Carlo Kopp                             [email-masked]
   Systems Research Group                 http://www.cs.monash.edu.au/~carlo
   Computer Science & Software Eng,       Ph: +61-3-9905-5229
   Monash Uni, Clayton, 3168, AUSTRALIA
   Kopp's Third Axiom : "The less substance to an opinion, the more 
                         vigorously it will be defended."
-------------------------------------------------------------------------------

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From: Fabrizio Talucci <[email-masked]>
Date: Mon, 6 Mar 2000 01:59:55 -0800 (PST)

> millions of spacemen roaming through the galaxy, creating ad-hoc

Prof., much more than that,
I can even envisage them manipulating their ad-hoc 'sensor' networks
in their 'Smart Environments', too !

 Fabrizio Talucci ;-]
 CSD-UCLA

---

From: Miguel Sanchez <[email-masked]>
Date: Mon, 06 Mar 2000 16:08:00 +0100

Hi Li, Mark and all,

Some (not necessary new) applications:

* Remote sensing (earthquakes, fire, environmental data gathering, ...): In
this application you can launch (robust) probes from a plane (maybe with
parachutes :-) without even landing. Data can be distributedly gathered, then
a special node (coordinator) will contact with the headquarter (with a sat
link or a higher power radio).

* Robotic communication (cleaning, firefighting, patrolling, oceanic fishing
(maybe not yet :-), farming,  planets surface exploration (think of several
Sojourners instead of just one) ... :  In this scenario, a set of mobile
robots are performing a local task, each one working in its own area. Group
coordination is done by means of a manet.

* Internet access: In some countries, Internet access is not available for a
(low) flat rate (i.e. most European countries). Students with housing near
university campus can build a manet (in this case with non-mobile hosts) to
access campus backbone (and Internet from there). While houses closer to
campus can have direct access, those far away can get through intermediate
routers. The high rate network changes can justifiy the use of manet protocols
(computers turned on, shutted down, reboots, OS features ...). This can add
mobile support for people carrying notebooks in their way to campus. (Don't
forget that CDPD, Rooftop, Metricom, etc are USA based, some other European
countries do not have any of these mobile data services and proposals like WAP
and GPRS are still in the early stage of deployment).

* LEO constellations: By itself could constitute a especial kind of manet.
(mobile nodes, limited transmission range, changing neigborhood, BUT a
predictable neighborhood switching scheme!).  I mean about inter-sat links.

Anyway, I think that some of the manet applications can exploit the advantages
of manet routing but then, manet can be interconnected to other
infrastructure-based networks.

No military application was cited. I hope this can help.

Best,

Miguel

--
Miguel Sanchez Lopez                            |       [email-masked]
Universidad Politecnica de Valencia             | voice:+3496 387 9700
Camino de Vera, 14                              | fax:  +3496 387 7579
46071 VALENCIA (Spain)                          |