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conceptual questions

I'd like to put some questions for the ns people:

I was examining the source code and documentation of ns, to try
to understand the dynamics of an actual node/ns node (which queues
and delays were involved - and what was left out). 

(Obs: fell free to point out segments of source code 
of current ns-2 distribution).

Is it correct to say that...

(a) ...packets arriving from all links end up into the node entry?

(b) ...that there is no queue between the node entry and the address
       classifier and replicator as well?

(c) ...that the task of classifying packets according to their addr,
       or 'replicating' a packet, does not have a time associated 
       with it (instantaneous)?

(d) ...if (c) is 'true', there is no bound for the rate in which
       a router could route/forward packets? (ignoring drops
       caused by overflow of the outgoing queues into links?)

(e) ...likewise, is there a bound in transmitting packets which
       were generated by a local agent (e.g., TCP source)? What
       if this agent is transmitting at a rate superior to
       the bandwidth of the outgoing link to be traversed
       by packets of this flow? Local drops?

(f) ...in case of a host receiving packets, addressed to a local
       agent, a transport layer sink. Is it possible that
       packets (from multiple links) arrive at a host at 
       a rate which is superior to the rate in which the
       sink agent is receiving such packets? Were drops modelled,
       in which queues that would be?

(g) ...all buffer management is done in a packet-basis, not byte,
       so that the packet size would not matter in regards to queue sizes
       and drops?

Please let me know if you find any questions which are unclear.

thanks very much for your time.
Marinho.
-- 
==== Antonio Marinho Pilla Barcellos ==================================
Ph.D. Student                                   phone: +44 191 222 8007
Department of Computing Science                 fax:   +44 191 222 8232
University of Newcastle upon Tyne   WWW: http://www.ncl.ac.uk/~n4521529
The United Kingdom NE1 7RU      e-mail: [email protected]  
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