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From: muts@fysaj.fys.ruu.nl (Peter Mutsaers /100000)
Newsgroups: comp.protocols.tcp-ip
Subject: Reliable connectionless (udp) sockets, who can help?
Message-ID: <1453@ruunsa.fys.ruu.nl>
Date: 7 Sep 90 11:18:33 GMT
Sender: news@ruunsa.fys.ruu.nl
Distribution: comp
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For a project on distributed computational physics I am
working on a small library to allow users easy access to 
N processes on different computers.

Because of the large number of process probably involved, I
do want to use connectionless (udp) sockets, but of course
I have to implement a protocol to provide reliable data
transmission.

My question is if someone has more information
(methods to implement, or maybe even unix-sources) on this,
as I don't like to spend time on something that has already
been done.

Maybe someone could also indicate to me if I am on the right way:
I have the following idea to implement it:
- each process has a generally known (address+port) udp socket,
  which is made asynchronous.
- a write operation sends packets to process i on some host,
  causing an interrupt. In the interrupt the packet is read
  and put in a buffer (N-1 buffers per host, one for each other process).
- a read operation reads from the buffer, and blocks if not enough
  data is in it. (by doing wait(), and check after a signal (SIGIO)
  if there is enough data now)


Thanks in advance,
--
Peter Mutsaers                          email:    muts@fysaj.fys.ruu.nl     
Rijksuniversiteit Utrecht                         nmutsaer@ruunsa.fys.ruu.nl
Princetonplein 5                          tel:    (+31)-(0)30-533880
3584 CG Utrecht, Netherlands