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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" <[email protected]>
To: "Ya Xu" <[email protected]>
Cc: <[email protected]>
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" <[email protected]>
> To: "Wings" <[email protected]>
> Cc: <[email protected]>
> 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
> > >
> > >
> >
>
>