Re: classifier and routing

[Tarik Alj <aljtarik@ozias.inrs-telecom.uquebec.ca>]

> X-Authentication-Warning: mash.CS.Berkeley.EDU: majrdomo set sender to 
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> From: "Huiwen Li" <huiwenli@nortelnetworks.com>
> To: "'ns-users@mash.cs.berkeley.edu'" <ns-users@mash.cs.berkeley.edu>
> Subject: classifier and routing
> Date: Fri, 15 Oct 1999 12:09:29 -0700
> MIME-Version: 1.0
> 
> Hello,
> 
> I have a question about classifier and routing. As I understand, so long as
> the topology and the traffic sources and destinations are built, if I am
> using the default routing logic, static routing, then all the routing tables
> are built and the slot_ in the classifier is already filled. As discussed in
> some previous emails, the procedure Simulator instproc compute-flat-route in
> ns-route.tcl points the classifier to the next hop object, which is defined
> by the routing logic. If I am wrong here, please point out to me.
> 
> In my case, I want to route the packets with flowid i to link i, which is
> like to differentiate these flows by their flow id. I am not sure how I can

Use a Hash/Fid classifier instead of the addr-classifier. This way you can 
classify packets on a fid basis.

You don't change the routing table but the classifier's entry.

> change the routing table after it is already set. I tried to use
> "$classifier install $i [[$ns link node1 node($i)] head]" after I built the

Maybe you should try using [$link_($node1_id)($node($i)_id) head]. Where link_ 
is Simulator's link array. 

And you could use add-route too.

Also, try dumping your classfier's content too ($classifier_ dump) and check if 
what you've installed in the slot $i is what you think it is (you should get a 
ref number for each slot, example:

(say we are dumping node n7's classifier)
dumping n7's class
classifier _o88
        0 offset
        8 shift
        127 mask
        7 slots
                slot 0: _o90
                slot 1: _o90
                slot 2: _o90
                slot 3: _o90
                slot 4: _o90
                slot 5: _o90
                slot 6: _o90

_o90 should be your link's head.
here n7 is connected to all the other nodes via the same link. 



> source, but it seems the routing works the same way as before.   
> 
> Can someone please give me some ideas how to solve this problem? Thanks a
> lot.
> 
> Huiwen

Hope i've helped, good luck Huiwen.

Tarik