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Re: [ns] Problem with connections



 
 I am a new user of 'ns' and this is what I can figure out.
 
--> Basically, there is no difference between 'connect' and
 'create-connection' except that latter one gives you a higher abstraction
 in the sense that you dont't have to create agents and attach them to
 nodes. The "create-connectionn' does it for you and moreover after doing
 so, it calls 'connect' proc. So, basically there is no difference between
 them.
 
--> Regarding the order of execution problem, I hope you may be detecting
 this problem because of the following thing. I think you created only
 one traffic agent and attached it to node 1. Then you possibly did
 
    $ns connect { $n1_agent  $n2_agent}
    $ns connect { $n1_agent  $n3_agent}
   
  Now, if you study the code of 'connect' in ns-lib.tcl , you will notice
 that it calls 'simplex-connect', which binds the destination adress and
 port to agents. So, calling the 'connect' twice with the same agent (in
 your case $n1_agent) would try to attach destination port and address
 to $n1_agent twice in succession, thus overriding the first call and
 only the last call effect would remain.  
 
 Hope it helps.
 
 Cheers !
 Amit
 
 ----------------------------------------------------------------------------
 Amit Jain
 Senior Undergraduate			Work Phone : 91-(0)512-597653
 Computer Science Department		Home Phone : 91-(0)512-597311
 Indian Institute Of Technology,
 Kanpur - 208016
 INDIA 
 
 
> On Sat, 27 Jan 2001, Christopher.Holtby wrote:
> 
> > Can anyone help me?
> > 
> > What is the difference between "$ns_ connect .." and "$ns_
> > create-connection .."?
> > 
> > If "connect" is used for two pairs of mobilenodes, why does it matter in
> > what order they are executed?
> > 
> > I'm trying to setup a connection from one mobilenode to two others, 
> > like this:
> >               1------2
> > 	       \
> >                 \
> >                  3
> > 
> > but can't seem to get both 2 & 3 to listen to 1. I'm sure the problem is
> > to do with "connect" but can't work out how to solve it.
> > 
> > Thanks,
> > 
> > Chris.
> > 
> 
>