Re: How to force a packet drop?

[Christos Papadopoulos <christos@dworkin.wustl.edu>]

Ahmed,

thanks again for your reply. I looked at errmodel.{h,cc} and I got
what I wanted. Quite nice.

The documentation in the main document is still not up to par. I am
sure that soon there will be more info along with examples.  I found
that the 4 lines (114-117) in srm-chain.tcl along with the C++ code,
are enough to help you understand how things work.

Christos.

------------ Ahmed A-G Helmy writes:
  > 
  > > Hi all,
  > > 
  > > what is the simplest way to force packet drop on an arbitrary
  > > link? I would like to control what packets are dropped, so I don't
  > > want to use TCP flows to saturate a link. I would also like deterministic
  > > and probablilistic drop. Is errormodel the right way to do it?
  > > How do you use it? I couldn't find any examples in the distribution.
  > 
  > I believe that error models are the right way.
  > There's support for lots of error models in NS, and there's a chapter in 
  > the ns documentation on it.
  > You can drop packets probabilistically, deterministically, or according to a 
  > trace file. 
  > 
  > You can drop per packet, byte, or specify what kind of 
  > packets to drop (e.g. SRM (check SRMErrorModel class), or PIM,Join (check 
  > MrouteErrormodel class)... etc) [but there's probably 
  > more work there if you want to specify new types, you can look in 
  > errmodel.cc for the C++ code].
  > 
  > The documentation is probably not up to date, but it's a good place to start,
  > http://www-mash.CS.Berkeley.EDU/ns/ns-documentation.html
  > 
  > Regards,
  > -A
  > 
  > > 
  > > Thanks,
  > > 
  > > Christos.
  > > 
  >