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Re: TCP packetSize
Anton,
from the Notes & doc (chapter 22) as of april 1 1999 : "packetSize_
essentialy functions like the MSS (Maximum segment size) in real world TCP".
There is a description of functions for sending data: send_much(...), and so on.
Have you been varying the window size too?
> Date: Fri, 10 Sep 1999 08:34:09 +0200
> From: Anton Riedl <[email protected]>
> X-Accept-Language: en,de
> MIME-Version: 1.0
> To: Tarik Alj <[email protected]>
> CC: [email protected]
> Subject: Re: TCP packetSize
> Content-Transfer-Encoding: 7bit
>
> Is packetSize_ the parameter for the *maximum* size of TCP packets or for the
size of *every* packet? What if the
> application has only a few bytes to send (n<packetSize_)?
>
> In my case, I have set packetSize_ to 1500. When my application sends 250
Bytes of data, it still results in a TCP packet
> with size 1500 (and not just 250). How can I make TCP send packets smaller
than packetSize_?
>
> - Anton
>
>
> > > I have the following two questions about ns-2.1b5:
> > >
> > > 1.)
> > > Is it possible to send TCP packets which are smaller than packetSize_ ?
> > > Although my application does a "sendmsg(n)" with n<packetSize_ , the
> > > tracefile still shows that the TCP packet is of size packetSize_ . The
> > > same is true when I do a "$tcp1 send n" in the script file.
> > > Do I have to set a certain parameter?
> > packetSize is the parameter: $source set packetSize_ $value
> > depending on your version of ns, maybe you should use packet_size_
> > >
> > > I checked the tcp source code (in tcp.cc) and it looks like tcp always
> > > sends packets with size_ = packetSize_ . UDP sources, however, do it
> > > differently. Is there a reason for that?
> > >
>
> ------------------------------------------------------------------------
> Anton Riedl
>
> Lehrstuhl fuer Kommunikationsnetze
> TU Muenchen, Arcisstr. 21, D-80290 Muenchen
> Tel: ++49 89 289-23506
> Email: [email protected]
> WWW: http://www.lkn.e-technik.tu-muenchen.de/~anton
> ------------------------------------------------------------------------
>
Tarik Alj
INRS-Telecommunications
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Verdun (Ile des Soeurs), Qc, H3E 1H6
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Tel: 514 761 8611
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