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Re: Classifier and Routing?



Hello,

> 	The classifier at a node is filled in ns-node.tcl, Node instproc 
> add-route; wich is called in ns-route.tcl's Simulator compute-flat-routes. 

    Thanks a lot! In the meantime, I am really sorry that I was not 
careful enough although I wanted. Currently, I know deeplier the 
relation between classifier and routing. Really thank you for your help.


> Concerning the classify() function, i 'm also trying to figure it out, 
> particularly the port classification: it seems classification happens on adress 
> and on port # at the same time? 

    Yes, it is a problem indeed. According to my understanding, 
classifiation does not happens on address and on port at the same 
time. The slot array of port classifier has been set just after we 
attach an agent to this node. So, the slot array of port classifier 
always keep right. Everytime, Routing just configures the slot array of 
address classifier ( in the Unicast Node). The statement about 
add-route on page 37 gives me such impresssion. 


> What if I need to access to different headers at 
> the same time to classify?     

    I do not know this question clearly. Why you need to access to 
different headers at the same time to classifier? I think the routing 
only use address field of a packet.

   I really appreciate your help !

   Best Regards,

   Sun Kai
  


> 	
> > X-Authentication-Warning: mash.CS.Berkeley.EDU: majrdomo set sender to 
> [email protected] using -f
> > From: K Sun <[email protected]>
> > To: [email protected]
> > Subject: Classifier and Routing?
> > Date: Fri, 1 Oct 1999 18:28:43 +0100 (GMT Daylight Time)
> > X-Authentication: IMSP
> > MIME-Version: 1.0
> > 
> > 
> > Hello,
> >      I am still confused with the relation between Classifier and 
> > Routing operation of ns, especially the operation of setting "slot" 
> > arrry.
> >      Actually, I have carefully read the chapter about Unicast Routing, 
> > but I do not find where a function of routing fills the suitable 
> > handlers of links (or connectors) in the "slot[]" array. 
> >      I have not known the function classify well. 
> > As my understanding, the number of elements of slot[] array ( at 
> > least in Address Classifier according to Figure 5.1 on page 35) should 
> > be one more than the number of links which are attached to this node. I 
> > am not sure whether my understanding is right.
> >      However, according to the code on page 40 and page 38, it seems 
> > the number of elements of "slot" arrary has should be the same as the 
> > number of nodes in topo because the classify function only shifts and 
> > masks the whole address (including node id and agent id). 
> > 
> >      Hope somebody may give me more implication on understanding 
> > classifier and routing!
> > 
> >      Thanks in advance,
> > 
> >      Sun Kai
> > 
> > 
> 
> Tarik