Subject: RE: [Ospf-manet] Initial Scenario Description

From: "Bose, Pratik" <[email-masked]>
Date: Tue, 10 Jan 2006 11:49:27 -0500

Hi, 
 
I finally got a chance to peruse through the information that Tom cited
below. After analyzing the wealth of information, I have the following
suggestions for OSPF-MANET scenarios for this mailing list to consider.
The motivation behind my comments is to consider the requirements of a
wider, more complete set of deployments for OSPF-MANET. The current
scenario is a great first step, we also need to address the requirements
of other networks whose characteristics can be different from the
current scenario. I try to cover nodes with different mobility
characteristics of multiple vehicle type (air, land and water) and I
think we all will notice that these can be so different that algorithm
evaluation should be subject to this variety: 
 
- Grid size and radio range: These two factors are clearly related. The
current scenario has 500 m^2 grid size and a radio range of 250 m. This
forms I think the spectrum of agile land based manet nodes with limited
mobility. It would help if the scenario allows these two parameters to
be specified as a ratio in metres for Grid Size / Range, with the
current scenario having a value of 2. At least a few more values of this
ratio is required such as 10, 50, 150 etc. This will cover cases where
long range radios can cover large grid sizes (some of which go into
kilometres - think large land vehicles, ships, planes). A corresponding
number of nodes would also apply to each case. 
 
- Velocity: The current scenario specifies 10 m/s . This is again
typical for certain land based vehicles only. In addition other mobile
node speeds need to be considered. Typical maritime speeds are double
the current number and airborne vehicle speeds begin at an order of
maginute greater upto Mach-1 speeds. 
 
- Pause Time: A pause time of 40 seconds in the current scenario is
sufficient for land vehicles for certain quick stationary activity. Both
shorter (air-vehicles) and larger (for both maritime and land vehicles)
pause time should also be considered ranging from the millisecond to
hour range. This can be done in discrete steps such that at least one
order of magnitude (millisecond, second, hour) is captured. Another
aspect of pause time implications which I could not find (maybe I missed
it) in the current scenario is that for most radios, the moment they
pause their radio range increases significantly. This is an important
aspect to consider, especially for large pause times. 
 
Although the above detail may seem involved, my guess is that all of the
above can be condensed to a handful of scenarios. The reason why I think
this is important is that the above characteristics are so different
that it seems moot that we as a group incorporate them in our evaluation
while we ponder on OSPF-MANET.  
 
Thanks, 
 
Pratik

  _____  

From: Henderson, Thomas R [mailto:[email-masked]] 
Sent: Thursday, December 01, 2005 10:35 AM
To: Bose, Pratik; [email-masked]
Subject: RE: [Ospf-manet] Initial Scenario Description

The code that implements this can be found at
SRC/mobility-random-waypoint.{cc,h}.  It is not documented anywhere else
AFAIK.  There are some other example scripts in the EXAMPLES/ directory
(testwirelessgrid*) that use the mobility models.  Also, the simulator
can be configured to generate animations such as shown in Figure A.6 of
the documentation, or at the website:
http://hipserver.mct.phantomworks.org/ietf/ospf/
 
Figure 4-1 describes what happens.  Each node starts at a random
location on the grid, picks a new random location on the grid, moves
there with constant velocity, and once there, pauses for a fixed amount
of time before picking a new random location.  In most of the plots in
the report, we used a grid size of 500 m^2, pause time of 40 seconds,
and velocity of 10 m/s, and a radio range of 250 m (the radio models are
described in more detail in Section 3.2).
 
Tom

  _____  

	From: Bose, Pratik [mailto:[email-masked]] 
	Sent: Thursday, December 01, 2005 6:59 AM
	To: [email-masked]
	Subject: [Ospf-manet] Initial Scenario Description

	Tom (and/or anyone else who knows)
	 
	I would like to understand the random way point scenario that
was conducted a bit better. Is there any more info that I can be pointed
to (more than what is in Section 4.1 of the current report). 
	 
	Thanks, 
	
	Pratik

_______________________________________________
Ospf-manet mailing list
[email-masked]
https://www1.ietf.org/mailman/listinfo/ospf-manet

---

From: Richard Ogier <[email-masked]>
Date: Fri, 13 Jan 2006 08:32:48 -0800

We had some discussion of scenarios on this list (e.g., my message on 
11/28 and
Abhay Roy's message on 11/30).  In my comments below, I repeat some of
my conclusions from that discussion.

Bose, Pratik wrote:

> Hi,
>
>  
>
> I finally got a chance to peruse through the information that Tom 
> cited below. After analyzing the wealth of information, I have the 
> following suggestions for OSPF-MANET scenarios for this mailing list 
> to consider. The motivation behind my comments is to consider the 
> requirements of a  wider, more complete set of deployments for 
> OSPF-MANET. The current scenario is a great first step, we also need 
> to address the requirements of other networks whose characteristics  
> can be different from the current scenario. I try to cover nodes with 
> different mobility characteristics of multiple vehicle type (air, land 
> and water) and I think we all will notice that these can be so 
> different that algorithm evaluation should be subject to this variety:
>
>  
>
> - Grid size and radio range: These two factors are clearly related. 
> The current scenario has 500 m^2 grid size and a radio range of 250 m. 
> This forms I think the spectrum of agile land based manet nodes with 
> limited mobility. It would help if the scenario allows these two 
> parameters to be specified as a ratio in metres for Grid Size / Range, 
> with the current scenario having a value of 2. At least a few more 
> values of this ratio is required such as 10, 50, 150 etc. This will 
> cover cases where long range radios can cover large grid sizes (some 
> of which go into kilometres - think large land vehicles, ships, 
> planes). A corresponding number of nodes would also apply to each case.
>
Roy suggested range/grid ratios of 0.25, 0.50, 0.75, and 1.0,
but I think the latter two are both very close to a fully connected network,
so my suggestion is to use the three ratios 0.25, 0.50, and 0.75.
Anything smaller than 0.25 will result in the network being partitioned
most of the time unless the number of nodes is more than about 50.
It may be possible to use a slightly smaller ratio for 100 nodes, such
as 0.20, but that is not much different from 0.25 (and we want to limit
the number of scenarios).

> maginute greater upto Mach-1 speeds.
Roy and I agreed that 5, 15, and 25 m/s are good choices.
I would also like to see results for 0 m/s (non-mobile), since
such networks can occur, and node movement can hide problems that
may occur when there is no movement (i.e., initial transient problems
may disappear when there is mobility, but may last a long time
if the topology does not change).  So maybe 0, 10, 20, and 30 m/s
are better choices.  I don't think higher speeds are within our scope.

I made other suggestions in my post on 11/28, such as the use of
a smaller Hello Interval for higher node speeds, so that the
packet delivery ratio is increased to reasonable levels.
E.g., perhaps use a Hello Interval of 1 second for node speeds
of 15 m/s and above. (It might also make sense to use smaller values
of other parameters such as MinLSInterval and RxmtInterval.)
Also, techniques that can be used by all proposed solutions, such
as the database exchange optimization described in the OSPF-MDR
draft, should be used by all solutions.

> sufficient for land vehicles for certain quick stationary activity. 
> Both shorter (air-vehicles) and larger (for both maritime and 
> land vehicles) pause time should also be considered ranging from the 
> millisecond to hour range. This can be done in discrete steps such 
> that at least one order of magnitude (millisecond, second, hour) is 
> captured. Another aspect of pause time implications which I could not 
> find (maybe I missed it) in the current scenario is that for most 
> radios, the moment they pause their radio range  increases 
> significantly. This is an important aspect to consider, especially for 
> large pause times.
>
>  
>
> Although the above detail may seem involved, my guess is that all of 
> the above can be condensed to a handful of scenarios.
>
Yes, for example 3 choices of range, 3 choices of node speed, and 4 
choices for
number of nodes (e.g., 25, 50, 75, 100) will result in 36 scenarios.

Richard

> The reason why I think this is important is that the above 
> characteristics are so different that it seems moot that we as a group 
> incorporate them in our evaluation while we ponder on OSPF-MANET. 
>
>  
>
> Thanks,
>
>  
>
> Pratik
>
>
> ------------------------------------------------------------------------
> SRC/mobility-random-waypoint.{cc,h}.  It is not documented anywhere 
> else AFAIK.  There are some other example scripts in the EXAMPLES/ 
> directory (testwirelessgrid*) that use the mobility models.  Also, the 
> simulator can be configured to generate animations such as shown in 
> Figure A.6 of the documentation, or at the website:  
> there with constant velocity, and once there, pauses for a fixed 
> amount of time before picking a new random location.  In most of the 
> plots in the report, we used a grid size of 500 m^2, pause time of 40 
> seconds, and velocity of 10 m/s, and a radio range of 250 m (the radio 
> models are described in more detail in Section 3.2).
>
>  
>
> Tom
>
>
>     ------------------------------------------------------------------------
>     I would like to understand the random way point scenario that was
>     conducted a bit better. Is there any more info that I can be
>     pointed to (more than what is in Section 4.1 of the current report).
>
>      
>
>     Thanks,
>
>
>     Pratik
>
>
>------------------------------------------------------------------------
>
>------------------------------------------------------------------------
>
>No virus found in this incoming message.
>Checked by AVG Free Edition.
>Version: 7.1.362 / Virus Database: 267.14.15/223 - Release Date: 1/6/2006
>

---

From: Philippe Jacquet <[email-masked]>
Date: Tue, 17 Jan 2006 14:37:38 +0100

Hi,

I worry that ad hoc communication between mobile moving at Mach 1 will 
be stressful for the physical layer. However it is interesting on the 
theoretical plan. I am currently investigating the effect of mobility up 
to that range for the routing protocols. It seems doable but you have of 
course to adapt the neighbour sensing with respect to this condition. 
The hello rate should be made such that the average link life time 
should be keep several time larger than the hello period. The link life 
time is proportional to radio range R and inversely proportional to 
speed difference Delta(v) (the correct formula with random motion is pi 
R/2/Delta(v)).

We have to be careful to the fact that according to Gupta and Kumar 
scaling property, optimal radio range R decays inversely proportionally 
to square root of traffic density, therefore increasing hello rate 
contributes to decrease optimal range. In my analysis I took the ratio 
link lifetime over hello rate equal to 100. In theory I can still 
control 500 jet fighters at Mach 1 if the density is 1 per square 
kilometre with a 1 Mbps channel. No idea on how realistic it is (and 
apologies for all Top Gun fans;-)) .

 Best regards,
Philippe

Bose, Pratik wrote:

> to address the requirements of other networks whose 
> characteristics can be different from the current scenario. I try to 
> cover nodes with different mobility characteristics of multiple 
> vehicle type (air, land and water) and I think we all will notice that 
> these can be so different that algorithm evaluation should be subject 
> to this variety:
>  
> the above can be condensed to a handful of scenarios. The reason why I 
> think this is important is that the above characteristics are so 
> different that it seems moot that we as a group incorporate them in 
> our evaluation while we ponder on OSPF-MANET. 
>  
> Thanks,
>  
> Pratik
>
> *From:* Henderson, Thomas R [mailto:[email-masked]]
> *Sent:* Thursday, December 01, 2005 10:35 AM
> *To:* Bose, Pratik; [email-masked]
> *Subject:* RE: [Ospf-manet] Initial Scenario Description
>
>     *From:* Bose, Pratik [mailto:[email-masked]]
>     *Sent:* Thursday, December 01, 2005 6:59 AM
>     *To:* [email-masked]
>     *Subject:* [Ospf-manet] Initial Scenario Description
>