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Re: Leaky Bucket ??

Hi,

find attached some messages from ns-users-mail archives. They will
probably answer your question.

Hope this will help you.

--------------
Vicent Pla

  
http://www-mash.cs.berkeley.edu/dist/archive/ns-users/9904/0206.html
Bodog Gyula wrote:
>
> Dear all,
>
> I used token bucket filter to my simulation. I'd lie to simulate some
> scheduling algorithm which is implemented in NS. I used CBR sources which are
> leaky bucket constrained.
>
> During the simulation I have a big problem. There are 7 session (7 CBR
> sources). Each can send packets from the begining of the simulation.
> But when used tbf, some sources doen't send any packet. However it should send
> packets with a specified rate.
>
> Has somybody know what could be the problem?
>
> Thanks ind advance,
>
> * * * * * * * * * * * * * * * * * * * * * * * * * * * *
> * Gyula Bodog *
> * e-mail: [email protected] *
> * tel.: (06 1) 3-691-839 *
> * Student at Technical University of Budapest *
> * *
> * * * * * * * * * * * * * * * * * * * * * * * * * * * *

A recently sent message mentionned this:

Hi,

We believe to have just found a bug in tbf.cc. Function TBF::recv has a
static variable "init", which gives wrong results when there is more
than one TBF object. We moved the "init" variable to the class
declaration in tbf.h as a protected variable, so that it can now work
fine with multiple TBF objects.

Lidia Yamamoto
Ludovic Kuty

The problem is: The first tbf starts with a full bucket and others tbfs start
with an empty bucket though they should also start with a full bucket.

Change the tbf code that way and it may resolve your problem.

Ludovic Kuty

Title: ns-users.archive.9904: Re: Token Bucket Filter

Re: Token Bucket Filter

Ludovic Kuty ([email protected])
Wed, 28 Apr 1999 14:55:39 +0200

Bodog Gyula wrote:
>
> Dear all,
>
> I used token bucket filter to my simulation. I'd lie to simulate some
> scheduling algorithm which is implemented in NS. I used CBR sources which are
> leaky bucket constrained.
>
> During the simulation I have a big problem. There are 7 session (7 CBR
> sources). Each can send packets from the begining of the simulation.
> But when used tbf, some sources doen't send any packet. However it should send
> packets with a specified rate.
>
> Has somybody know what could be the problem?
>
> Thanks ind advance,
>
> * * * * * * * * * * * * * * * * * * * * * * * * * * * *
> * Gyula Bodog *
> * e-mail: [email protected] *
> * tel.: (06 1) 3-691-839 *
> * Student at Technical University of Budapest *
> * *
> * * * * * * * * * * * * * * * * * * * * * * * * * * * *

A recently sent message mentionned this:

Hi,

We believe to have just found a bug in tbf.cc. Function TBF::recv has a
static variable "init", which gives wrong results when there is more
than one TBF object. We moved the "init" variable to the class
declaration in tbf.h as a protected variable, so that it can now work
fine with multiple TBF objects.

Lidia Yamamoto
Ludovic Kuty

The problem is: The first tbf starts with a full bucket and others tbfs start
with an empty bucket though they should also start with a full bucket.

Change the tbf code that way and it may resolve your problem.

Ludovic Kuty



  
http://www-mash.cs.berkeley.edu/dist/archive/ns-users/9903/0123.html
> Hi
>
> Where and how do we use filter in ns?
> Where can i get details on token bucket filter in ns?

Take a look the files: tbf.h, tbf.cc, and tcl/ex/test-tbf.tcl

Thanks.
--Zhenhai
>
> thanks
>
> with Regards
> Anurag,
>
>

Title: ns-users.archive.9903: Re: filter and token bucket filter

Re: filter and token bucket filter

Zhenhai Duan ([email protected])
Fri, 12 Mar 1999 10:06:41 -0600 (CST)

> Hi
>
> Where and how do we use filter in ns?
> Where can i get details on token bucket filter in ns?

Take a look the files: tbf.h, tbf.cc, and tcl/ex/test-tbf.tcl

Thanks.
--Zhenhai
>
> thanks
>
> with Regards
> Anurag,
>
>



  
http://www-mash.cs.berkeley.edu/dist/archive/ns-users/9903/0186.html
HI Zhen,

Did u consider the two token rate tbf (as defined in )

ftp://lohi.eng.telia.fi/tmp/draft-heinanen-diffserv-trtcm-00.txt

It is simple...

Just put two tbfs in succession::

Pkt flow----> TBF1 ----> TBF2---->Pkt Flow

TBF1 parameters: rate = average rate of the flow= token rate
TBF2 parameters: rate = peak rate of the flow= token rate

The bucket depths are left to your choice...

Will this work for u?? Just thought I should tell you..

Arni

On Tue, 2 Mar 1999, Zhenhai Duan wrote:

> I just checked the code of tbf, and I want to add in the Peak Rate
> contraint. But I am not sure how I should use this value. The way in my
> mind is this: Whenever I have enough tokens to send one packet, I postpone
> (scheduling a event) the sending by a delay(packetLength/peakRate), after
> timeout, I call target_->recv(p).
>
> Any comments are appreciated.

Title: ns-users.archive.9903: Re: about TBF(Token Bucket Filter)

Re: about TBF(Token Bucket Filter)

[email protected]
Wed, 17 Mar 1999 23:16:31 -0500 (EST)

HI Zhen,

Did u consider the two token rate tbf (as defined in )

ftp://lohi.eng.telia.fi/tmp/draft-heinanen-diffserv-trtcm-00.txt

It is simple...

Just put two tbfs in succession::

Pkt flow----> TBF1 ----> TBF2---->Pkt Flow

TBF1 parameters: rate = average rate of the flow= token rate
TBF2 parameters: rate = peak rate of the flow= token rate

The bucket depths are left to your choice...

Will this work for u?? Just thought I should tell you..

Arni

On Tue, 2 Mar 1999, Zhenhai Duan wrote:

> I just checked the code of tbf, and I want to add in the Peak Rate
> contraint. But I am not sure how I should use this value. The way in my
> mind is this: Whenever I have enough tokens to send one packet, I postpone
> (scheduling a event) the sending by a delay(packetLength/peakRate), after
> timeout, I call target_->recv(p).
>
> Any comments are appreciated.
> --Zhenhai
> --------------------------------------------------------------
> Zhenhai Duan [email protected]
> Computer Science Department http://www.cs.umn.edu/~duan
> University of Minnesota, TC Phone: (612)626-7526(O)
> --------------------------------------------------------------
>
>