[ns] Com. Range & Max Propagation Delay

[Bahman Kalantari Sabet]

Hi Luigi (and of course to other NS members)

Regarding your email on changing the Max Propagation Delay, how and where 
can I
change this value? (I checked the ns-default.tcl, but couldn't find 
anything!)

How ,for instance, do I calculate the 'propagation delay' value for a 
distance of 10km
between two mobile nodes?


>From: Luigi Iannone <Luigi.Iannone at lip6.fr>
>To: ns-users at ISI.EDU
>Subject: Re: [ns] Communication Range in 802.11
>Date: Fri, 2 Sep 2005 11:37:52 +0200 (CEST)
>
>
>Hi Bahman,
>
>You have also to change the Max Propagation Delay constant used to set up 
>timeouts. Else even if you correctly set up transmission power for 10000 
>meters communication your timeout will expire before you receive back the 
>ACK.
>
>Ciao
>
>Luigi
>
>
>>
>>Message: 7
>>Date: Thu, 1 Sep 2005 14:29:29 -0400
>>From: Cevher Dogan <cevherd at gmail.com>
>>Subject: Re: [ns] Communication Range in 802.11
>>To: Bahman Kalantari Sabet <behmans at hotmail.com>
>>Cc: ns-users at ISI.EDU
>>Message-ID: <c6d3fc7405090111295a3975f at mail.gmail.com>
>>Content-Type: text/plain; charset=ISO-8859-1
>>
>>Bahman,
>>
>>There are many options provided with the possibilities of wireless card
>>specifications in the market. NS2 code has hardcoded contants in
>>ns-default.tcl for receive and carrier sense thresholds and transmit 
>>power.
>>This is just a sample retreived as a reference to a particular card 
>>(Lucent)
>>in the market.
>>
>>you can basically change Pt_ and/or transmission range using threshold
>>utility to find out what RXThresh_ would be. In this junction, you can
>>prefer to be theoritical or actual (with reference to an existing wireless
>>card specifications).
>>
>>Just plug in the Pt_ and RXThresh_ in ns-default.tcl, and recompile and
>>install ns2 again, then you would be all set to go.
>>
>>Cevher
>>
>>
>>On 9/1/05, Bahman Kalantari Sabet <behmans at hotmail.com> wrote:
>>>
>>>
>>>Hi everyone,
>>>
>>>I was wondering how it is possible to increase the communication range
>>>between
>>>two mobile nodes which are using FTP/TCP in a 802.11 system.
>>>
>>>I have been told to go to '~ns~indep-utitls/propagation' and compile
>>>threshold.cc
>>>i.e. g++ -Wno-deprecated threshold.cc -o threshold.
>>>So I did this by putting a distance of 10.000 metres and I got 
>>>1.42681e-16
>>>for
>>>the RXThresh_ (which I put in my tcl file)
>>>
>>>The problem is that when I put the distance between two nodes more than
>>>500
>>>metres, then I wouldn't get any throughput!
>>>
>>>I thought that I can go up to 10000 metres now?!
>>>
>>>Any suggestions on how to increase the communication range between two
>>>nodes??
>>>
>>>Regards,
>>>
>>>Bahman.
>>>
>>>
>>>
>>
>>
>>------------------------------
>>
>
>----------------------------------------------------------->
>The man who follows the crowd will usually get no further
>    than the crowd.
>
>The man who walks alone is likely to find himself in places no
>    one has ever been.
>                                         (Alan Ashley-Pitt)
>------------------------------------>
>Luigi Iannone -  Laboratoire D'Informatique Paris 6
>    Address:	 8, rue du Cap. Scott 75015 Paris (France)
>    e.mail:       luigi.iannone at lip6.fr
>    Tel:          +33 (0)1 44 27 71 28