[omniORB] UDP/other protocols

mdavis@rwii.com mdavis@rwii.com
Mon, 12 Jun 2000 17:50:12 -0400


I realize this response is well out of date, given the date this message was
sent (over a yyear ago), but I am having some difficulties.

I am working on a large project, and some factions are pushing for some of
the data to be over UDP, so that there are no TCP retries, etc.  Basically,
we have a network such that connections could drop out and return randomly
based on any number of things, as it is over a radio-ethernet link to a
mobile platform.  There may be a relay station between the mobile platform
and the ultimate destination of the data.  The people pushing for UDP are
doing so to avoid flodding the relay station with attempted retries as
connection s come and go. I have been pushing to keep everything in TCP, 
and find other ways to deal with this issue.

Does anyone have any suggestions about how to limit the number of TCP
retries, or plug in a protocol that would avoid the retry problem?

I know that ORBacus for Java supports a Timeout policy.  Also, I know we
could use one-way requests.  Does this solve my problem, or does it hide the
retries from me?  If it DOES solve my problem, does OmniORB 2.8 support a
Timeout policy?  What about OnmiORB 3.0?

At one point in the past, for another project with truly wierd goals, I
implemented another protocol under OmniORB 2.7 that communicated to a single
object over a serial line.  It was not pretty, and I would rather not do it
again, but if that is the only way to get what I need, then I may have to do
it again.  :(

I appreciate any information that can be provided.

> Gary D. Duzan (gdd0@gte.com)
> Thu, 07 Jan 1999 09:10:32 -0500 
> 
>    Well, strictly speaking you can't do GIOP over a connectionless
> transport since it is inherently connection-oriented, but not all
> CORBA communication has to be GIOP-based.
> 
>                                         Gary Duzan
>                                         GTE Laboratories
> 
> In Message <001601be39db$2e073d40$0500000a@cc702523-a.hwrd1.md.home.com> ,
>    "Doug Anderson" <doug@clark.net> wrote:
> 
> =>Hi,
> =>
> =>Sai Lai wrote:
> =>>Unlike other ORBs, there is no way to insert a handler into omniORB2 to
> get
> =>>a callback when a connection is made or when it is broken. It is my
> opinion
> =>>that using the status of network connections to detect client failure is
> =>>a poor way of doing the job and does not fit in very well with the CORBA
> =>>framework. It is the job of the ORB to decide when is the best time to
> =>>establish a connection and how many connections are necessary to
> =>communicate
> =>>with the server.
> =>
> =>Not to mention the fact that this would not work well in a connection-LESS
> =>GIOP implementation, ala IIOP over UDP?? (if and when such a beast
> =>becomes commonplace!)
> =>
> =>Doug
> =>
> =>
> =>
-- 
Mike Davis           Real World Interface, a division of I.S. Robotics
mdavis@rwii.com      http://www.rwii.com
603-532-6900 x215    fax : 603-532-6901