Re: where to add marker for packets (for diff-serv)

[Yuri Pryadkin <yuri@who.isi.edu>]

Urs Thuermann <thuerman@ibr.cs.tu-bs.de> writes:

> yuri@who.isi.edu (Yuri Pryadkin) writes:
> 
> > Urs Thuermann <thuerman@ibr.cs.tu-bs.de> writes:
> > 
> > > Since in contrast to the ns documnetation a node has no entry_
> > > instance variable, I tried to insert my packet marker in place of the
> > > node's classifier:
> > > 
> > > 	set n [$ns node]
> > > 	set m [new Marker]
> > > 	$m target [$n set classifier_]
> > > 	$n set classifier_ $m
> > 
> > See 'Node instproc entry'
> 
> I can't use entry{} to install my packet marker in front of the
> classifier.  entry{} only allows you to *get* a reference to the
> node's entry point.
> 
> I still don't know how to place the packet marker into the node.

Well, you can call it a hack, but it seems to me that you could derive
your Marker from AddressClassifier, override recv(...) so that it does
your marking first and then calls AddressClassifier::recv(...); an
alternative would be to hack ns tcl node structure.

> 
> > You might consider using MultiFieldFilter for your purposes...
> 
> What are these and how are they used?  Is it documented somewhere?

Have a look at filter.h, filter.cc.

> 
> 
> urs

 - Yuri