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Re: [ns] Documentation on CBQLink and CBQ Objects



> Thanks Carlos,
> Can I use Tcl procedure to implement CBQ as object of the node rather than
> it being an object of Link. I mean without changing the base C/C++ code.

Queues in ns are implemented within links, because (as Tarik pointed out)
links are just abstractions of output ports.
So, I think neither this is possible without a big change in ns, nor it is
necessary!
As CBQ is a kind of queueing mechanism, the this reasoning is valid for it
as well.

Carlos


>  
> At 10:46 22/11/00 -0300, you wrote:
> >> Hi Carlos,
> >> Thanks very much for your prompt reply.
> >> Yet again, I have two straight forward questions whose answers are dicey in
> >> my mind just now;
> >> (1) If I have a link between n0 and n1 with CBQ,
> >>       n0---------n1
> >> Where is the CBQ implemented, is it at the output of n0 or at the imput
> of n1?
> >
> >At the link between n0 and n1 (that represents the output of n0)
> >
> >> (2) If cbqlink is not implemented between n0 and n1, can one still
> implement 
> >> CBQ in the link?
> >
> >As CBQ is implemented at the link, there is no another way of implementing
> >it.
> >
> >Carlos
> >
> >> 
> >> At 14:53 13/11/00 -0300, you wrote:
> >> >> I want packets from n0 and n1 to be queued in different queues at n2
> before
> >> >> being forwarded to n3. Since NS do not implement CBQ as object of the
> node,
> >> >> I have problem in  managing CBQ in n2. The question is, for me to
> implement
> >> >> multiple Queue in n2 only, must I install cbqlink in the 3 links?
> Does NS
> >> >> allow you to define a procedure that enable you to install multiple
> queues
> >> >> in a node?
> >> >
> >> >NS implements queues within link objects. So, in order to get the effect
> >> >of having multiple queues in node n2, you just need to set a CBQ link
> >> >between nodes n2 and n3.
> >> >
> >> >> I have the ./ns test-suite-cbq.tcl. The script confuse me in terms of
> how
> >> >> the events are related to the topology or nodes for the simulation.
> >> >
> >> >Take a look in the following simple script:
> >> >http://www.cin.ufpe.br/~cak/ns/cbq_example.tcl
> >> >
> >> >> 
> >> >> I also have problem with implementation of CBQ using TCP as transport
> >> agent.
> >> >
> >> >If use set a CBQ duplex-link you need to configure CBQ queues in both
> >> >directions, i.e., link n2-n3 and n3-n2. 
> >> >Since TCP agents have acks flowing in the opposite direction of the flow,
> >> >you need either to configure a CBQ as a simplex-link or (if you choose
> >> >to use a duplex-link) to configure CBQ in both directions.
> >> >
> >> >Carlos
> >> >
> >> >> 
> >> >> I will appreciate your help on this and thanks so much for your help so
> >> far.
> >> >> I will be grateful to anybody that can help on this.
> >> >> 
> >> >>  
> >> >> At 10:05 09/11/00 -0500, John Mehringer wrote:
> >> >> >Links to ns documentation can be found at the following link.
> >> >> >
> >> >> >http://www.isi.edu/nsnam/ns/index.html
> >> >> >
> >> >> > - John
> >> >> >
> >> >> >Titus Awotula wrote:
> >> >> >
> >> >> >> Hi All,
> >> >> >> I will be grateful if anybody can send me a link or information on
> the
> >> >> >> documentation on the use of CBQlink and CBQ Objects in NS.
> >> >> >> Please it is urgent.
> >> >> >> Titus Awotula, MSc AMIEE
> >> >> >> Dept. of Electronic & Electrical Engineering
> >> >> >> Loughborough University
> >> >> >> Loughborough.
> >> >> >> Leicestershire LE11 3TU
> >> >> >> Tel: Office (01509) 228117
> >> >> >>      Home   (01509) 558102
> >> >> >> Fax: (01509) 227014
> >> >> >
> >> >> >
> >> >> >
> >> >> Titus Awotula, MSc AMIEE
> >> >> Dept. of Electronic & Electrical Engineering
> >> >> Loughborough University
> >> >> Loughborough.
> >> >> Leicestershire LE11 3TU
> >> >> Tel: Office (01509) 228117
> >> >>      Home   (01509) 558102  
> >> >> Fax: (01509) 227014
> >> >> 
> >> >
> >> >
> >> >
> >> Titus Awotula, MSc AMIEE
> >> Dept. of Electronic & Electrical Engineering
> >> Loughborough University
> >> Loughborough.
> >> Leicestershire LE11 3TU
> >> Tel: Office (01509) 228117
> >>      Home   (01509) 558102  
> >> Fax: (01509) 227014
> >> 
> >
> >
> >
> Titus Awotula, MSc AMIEE
> Dept. of Electronic & Electrical Engineering
> Loughborough University
> Loughborough.
> Leicestershire LE11 3TU
> Tel: Office (01509) 228117
>      Home   (01509) 558102  
> Fax: (01509) 227014
>