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Re: [ns] Problems using TcpApp wit FullTcp
We will fix it asap. Thanks.
-chen xuan
On Sat, 9 Dec 2000, Felix Hernandez Campos wrote:
> I'm not sure this is going to fix your problem, but it will help. reset is
> partially broken in FullTcp. The main problem is that closed_ is defined in
> tcp.h and then redefined in tcp-full.h. This *is* wrong. I submitted a bug
> report three month ago, but it has not been committed yet. Read my (lengthy)
> posting for more details,
>
> http://www.isi.edu/nsnam/archive/ns-users/webarch/2000/msg03812.html
>
> (see also John Heidemann's reply:
> http://www.isi.edu/nsnam/archive/ns-users/webarch/2000/msg03859.html)
>
> You may want to contact Tarik Alj ([email protected]). He was
> doing real work with FullTcp at that time, while I was just trying to help. He
> may have a more mature version of FullTcp.
>
> By the way, someone with writing access should have a look to this and make some
> changes. Thanks.
>
> Mark Janssen wrote:
>
> > Hello all,
> >
> > I am trying to use TcpApp over FullTcp to simulate some application
> > behaviour. While doing that I run into a problem while connecting different
> > apps. What I would like to accomplish is the following:
> >
> > I have a linear topology of three nodes with an attached FullTcp agent:
> >
> > (1)-----------(2)-----------(3)
> >
> > After that I create three apps and put the TCP agent at the second node in
> > the listen state. And connect tcp1 with tcp2 with app1 and app2.
> > Now app1 sends a message to app2. This all works great. Now because of this
> > message app2 needs to contact app3. So I connect tcp2 with tcp3 and app2
> > with app3 and I put tcp3 in listen mode.
> > When I now send a message from app2 to app3 I only see ACK packets without
> > TCP packets. I suspect this occurs because tcp2 is still in a different
> > state then when you create it. I tried to do a "$tcp2 reset" but that
> > doesn't solve my problem. Below I have include the tcl script, the ns output
> > and the tracefile.
> > Unfortunately I couldn't find any information on this in the documentation
> > or the list-archive. I have looked at the webcache testsuite. But that only
> > test a 2-node setup (with TcpApp and FullTcp) and that works fine.
> > Do you have any ideas of how I should accomplish this?
> >
> > Thanks,
> > Mark Janssen
> >
> > ###begin tcpapp.tcl
> > #Create a simulator object
> > set ns [new Simulator]
> >
> > #Open the nam trace file
> > set nf [open out.nam w]
> > $ns namtrace-all $nf
> >
> > #Open the trace file
> > set f [open out.tr w]
> > $ns trace-all $f
> >
> > #Define a 'finish' procedure
> > proc finish {} {
> > global ns nf f
> > $ns flush-trace
> > close $f
> > #Close the trace file
> > close $nf
> > #Execute nam on the trace file
> > # exec nam out.nam &
> > exit 0
> > }
> >
> > set n1 [$ns node]
> > set n2 [$ns node]
> > set n3 [$ns node]
> > $ns duplex-link $n1 $n2 1Mb 80ms DropTail
> > $ns duplex-link $n2 $n3 1Mb 80ms DropTail
> >
> > Application/TcpApp instproc app-recv {src size} {
> > global ns
> > puts "[$ns now] $self recieves data $size from $src"
> > $ns trace-annotate "$self recieves data $size from $src"
> > # $self send 100 "$self send 100 \"$src app-recv $self 100\""
> >
> > }
> >
> > set tcp1 [new Agent/TCP/FullTcp]
> > set tcp2 [new Agent/TCP/FullTcp]
> > set tcp3 [new Agent/TCP/FullTcp]
> >
> > $ns attach-agent $n1 $tcp1
> > $ns attach-agent $n2 $tcp2
> > $ns attach-agent $n2 $tcp3
> >
> > set app1 [new Application/TcpApp $tcp1]
> > set app2 [new Application/TcpApp $tcp2]
> > set app3 [new Application/TcpApp $tcp3]
> >
> > $ns connect $tcp1 $tcp2
> > $app1 connect $app2
> > #Call the finish procedure after 5 seconds of simulation time
> > $ns at 0.1 "$tcp2 listen ; $app1 send 100 \"$app2 app-recv $app1 100\""
> > $ns at 4.0 "$ns connect $tcp2 $tcp3 ; $app2 connect $app3; $tcp3 listen;
> > $app2 send 100 \"$app3 app-recv $app2 100\""
> > $ns at 7.0 "finish"
> > #Run the simulation
> > $ns run
> > ###end tcpapp.tcl
> >
> > ###begin ns-output
> > [mjanssen@mjlaptop myscripts]$ ns tcpapp.tcl
> > 0.34207999999999994 _o65 recieves data 100 from _o64
> > 4.000000: FullTcpAgent::recv(_o60) got packet lacking ACK (seq 101)
> > 4.100000: (_o61) unexpected timeout 3 in state 1
> > 4.600000: FullTcpAgent::recv(_o60) got packet lacking ACK (seq 101)
> > 4.600000: (_o61) unexpected timeout 3 in state 1
> > 5.800000: FullTcpAgent::recv(_o60) got packet lacking ACK (seq 101)
> > 5.800000: (_o61) unexpected timeout 3 in state 1
> > [mjanssen@mjlaptop myscripts]$
> > ###end ns-output
> >
> > ###begin out.tr
> > + 0.1 0 1 tcp 40 ------- 0 0.0 1.0 0 0
> > - 0.1 0 1 tcp 40 ------- 0 0.0 1.0 0 0
> > r 0.18032 0 1 tcp 40 ------- 0 0.0 1.0 0 0
> > + 0.18032 1 0 ack 40 ------- 0 1.0 0.0 0 1
> > - 0.18032 1 0 ack 40 ------- 0 1.0 0.0 0 1
> > r 0.26064 1 0 ack 40 ------- 0 1.0 0.0 0 1
> > + 0.26064 0 1 tcp 40 ------- 0 0.0 1.0 1 2
> > - 0.26064 0 1 tcp 40 ------- 0 0.0 1.0 1 2
> > + 0.26064 0 1 tcp 140 ------- 0 0.0 1.0 1 3
> > - 0.26096 0 1 tcp 140 ------- 0 0.0 1.0 1 3
> > r 0.34096 0 1 tcp 40 ------- 0 0.0 1.0 1 2
> > r 0.34208 0 1 tcp 140 ------- 0 0.0 1.0 1 3
> > v 0.34207999999999994 eval {set sim_annotation {_o65 recieves data 100 from
> > _o64}}
> > + 0.4 1 0 ack 40 ------- 0 1.0 0.0 1 4
> > - 0.4 1 0 ack 40 ------- 0 1.0 0.0 1 4
> > r 0.48032 1 0 ack 40 ------- 0 1.0 0.0 1 4
> > ###end out.tr
>
> --
> ______________________________________________________
>
> Felix Hernandez Campos - [email protected]
> ______________________________________________________
>
> Graduate Student & Research Assistant
> Phone#: (919) 962-1948
> University of North Carolina at Chapel Hill
> Department of Computer Science, Room# 145
> CB# 3175, Sitterson Hall
> Chapel Hill, NC 27599-3175
> ______________________________________________________
>
>
>
--
Xuan Chen
ISI/USC