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Re: [ns] About wireless bandwidth



If you use IEEE 802.11, you can set in your tcl file as:
Mac/802_11 set bandwidth_ 2mb

AFAIK, you should put the command before your node config statement.
Otherwise it will not work.
----- Original Message -----
From: "Wings" <wings@cis.nctu.edu.tw>
To: "Jun Zhao" <JZhao_NS@hotmail.com>; "Ya Xu" <yaxu@isi.edu>
Cc: <ns-users@isi.edu>
Sent: Wednesday, October 17, 2001 11:10 AM
Subject: Re: [ns] About wireless bandwidth


> Dear Sir,
>
>     I f  I want to set the MAC bandwidth of wired link , how can I do?
>     Thanks.
>
> Wings
>
> ----- Original Message -----
> From: "Jun Zhao" <JZhao_NS@hotmail.com>
> To: "Wings" <wings@cis.nctu.edu.tw>; "Ya Xu" <yaxu@ISI.EDU>
> Cc: <ns-users@ISI.EDU>
> Sent: Tuesday, October 16, 2001 2:39 PM
> Subject: Re: [ns] About wireless bandwidth
>
>
> > I think bandwidth at link is not the same as in MAC or PHY. If one set
MAC
> > bandwidth_ as 10mb, the equivalent bandwidth_ seen from higher layers
may
> be
> > 8mb or less.
> > ----- Original Message -----
> > From: "Wings" <wings@cis.nctu.edu.tw>
> > To: "Ya Xu" <yaxu@ISI.EDU>
> > Cc: <ns-users@ISI.EDU>
> > Sent: Monday, October 15, 2001 12:49 PM
> > Subject: Re: [ns] About wireless bandwidth
> >
> >
> > >
> > > Dear Sir,
> > >
> > > I calculate the TCP packet seq. numbers as the rate.
> > > For example,set TCP PacketSize=1000bytes , time=Ts
> > >                              1000*8*seq. num
> > >                     rate=--------------------- = x bps
> > >                                         T
> > > The calculate rate with such method is the rate of application ?
> > >
> > > Besides, I run the simulation in wired network and set link bandwidth
> > 2Mbps.
> > > Its rate can achieve 2Mbps. Why? The overhead doesn't exist in wired ?
> > >
> > >     Thanks.
> > >
> > > Wings
> > >
> > > ----- Original Message -----
> > > From: "Ya Xu" <yaxu@ISI.EDU>
> > > To: "Wings" <wings@cis.nctu.edu.tw>
> > > Cc: <ns-users@ISI.EDU>
> > > Sent: Sunday, October 14, 2001 2:12 AM
> > > Subject: Re: [ns] About wireless bandwidth
> > >
> > >
> > > >
> > > > If you are talking about the rate of your application,
> > > > it can not reach 2M because of the protocol overhead in
> > > > transport and mac etc.
> > > >
> > > > -ya
> > > >
> > > > On Fri, 12 Oct 2001, Wings wrote:
> > > >
> > > > > Dear ns-users,
> > > > >
> > > > >     The default value of wireless bandwidth is 2Mbps.
> > > > > Because wireless channel is broadcast environment.
> > > > > if only one TCP flow is start up,it can use all the channel.
> > > > > But its rate can't achieve 2Mbps. Why?
> > > > >
> > > > >     Thanks.
> > > > >
> > > > > Best regard,
> > > > > Wings
> > > > >
> > > > >
> > > >
> > >
> > >
> >
>
>