Re: [ns] how to set a tcp header field?

[Sudhindra Suresh Bengeri <ssbenger@unity.ncsu.edu>]

Klaus,

The nortel impl of diffserv assigns codepoints based on <src, dst> as
specified in the  Policy table entries (added by addPolicyEntry) and yes
that means a node 'src' can send only one type of data traffic towards a
node 'dst' the code points are stored in the hdr_ip::prio_ field.

Also the nortel impl. has not specified the codepoint to phb mapping, ie
best-effort/ef treatment depends on the parameters you associate with the
code points.

Hence you will have to set up appropriate policy/phb table entries, and
policer and Q parameters. Your agents need not change if ur configure the
diffserv edge que properly. If however u want to associate multiple flows
originating from a src and destined to the same dst, then u will have to
make changes to the Policy class(dsPolicy.cc/h) and addPolicyEntry
commands (edge.cc/h) etc,

I don't think I am answering your questio to the point, anyway I think it
gives you some pointers to start thinking about ur simulation.

regards,
Sudhin.

On Sun, 15 Apr 2001, Klaus Danner wrote:

> Hi,
>
> I want to set a specific value in the ToS field (a CodePoint for DiffServ) in IPv4 traffic
> which is produced by a agent. How do I do it in my tcl-file?
>
> I have a DiffServ domain and one node should send background traffic, this means flows
> with different CodePoints (best-efford, expedited forwarding) produced by different
> agents. Can I configure a agent, that it sends packets with a specific codepoint?
>
> I tried to find the answer in the ns-doc and the mailing-list, but I didn't get a hint how
> to do it.
> Thanks a lot for your help.
> Klaus
>
>

****************** Sudhindra Suresh Bengeri ********************
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* Always glad to share my ignorance - I've got plenty. *