I can speak to RTI-NG on this issue.

Staring with version 6 of RTI-NG (Due out the end this month), the RTI can
be placed into a ``connectionless`` mode.  Using this setting, no reliable
connections are made between federates and there are no centralized
processes, such as the rtiexec or fedex.   Certainly, this is a
non-compliant mode for the RTI, however offers a light weight, high
performance  capability for those federations which do not use any of the
services lost as a result of not having reliable connections, such as time
management.  Federates that wish to run in this mode must first call
createFederationExecution before joining the federation in order to read in
the FED file.

The compliant, out-of-the-box configuration for RTI-NG does not require the
call to create as long as the federation already exists.  In this case, the
fedex process stores the FED file and joining federates will retrieve it
from that process.  However, I was under the impression that for a federate
to certified as HLA compliant, that it must call create before calling
join.  Does anyone know if this is or is not a requirement for certification?


At Thursday 09:51 PM 7/18/2002, you wrote:

>Are you referring to current RTIs, older ones, or some of each?  I can
>understand why someone first trying to get an RTI working might take that
>kind of shortcut, but I really don`t think an RTI that behaves that way
>ought to be regarded as compliant.  Basically, such an RTI is modifying the
>semantics of ``Create Federation Execution`` to make them something other than
>what the Interface Specification says.  Federates should not have to risk
>creating a federation when they don`t want to just to initialize!
>Suppose a federate designer wanted to take advantage of the Interface
>Specification`s design to have a federate operate continually in standby
>mode attempting to join a federation (if it exists) every second or so.
>Unless I`m forgetting something, that ought to be possible, with the
>federate getting exceptions on the join operation until someone creates the
>federation execution.  But with ``create to initialize`` semantics, it`s hard
>to imagine how even one such federate could be built successfully, and I
>can`t see at all how several could coexist peaceably in the same federation.
>Nathan A. Barclay
>Teledyne Brown Engineering
>-----Original Message-----
>From: William K. Andrews [mailto:[log in to unmask]]
>Sent: Thursday, July 18, 2002 7:54 PM
>To: SISO - Run-Time Infrastructure and Communications Forum
>Subject: Re: Creating and Destroying Federations
>One thing to keep in mind is that some RTIs require the creat attempt as
>that is how/when they parse the FED file.  Without the create attempt, they
>will not fully function.  Not all of them work this way, but several do.
>One thing I have seen is a secondary federation executive style progress
>that is sort of the game master. It handles initialization control so that
>order is not an issues and makes sure late joiners do not pick a bad time to
>spike the net...
>Bill Andrews
>----- Original Message -----
>From: ``Barclay, Nathan`` <[log in to unmask]>
>To: ``SISO - Run-Time Infrastructure and Communications Forum``
><[log in to unmask]>
>Sent: Thursday, July 18, 2002 7:26 PM
>Subject: RE: Creating and Destroying Federations
> >
> > My understanding is that having every federate try to create the
> > before joining is merely a very popular convention - more or less a de
> > standard, but not an official one.  It makes sure that no matter what
> > federates are run (even federates originally designed for different
> > federations, if they`re compatible) or what order they are started in, the
> > federates can join.  But on the other hand, I can envision situations
> > a federation planner might want one particular federate always to start
> > federation.  In such a case, making sure some other federate won`t start
> > federation first by accident could be useful.
> >
> > Nathan A. Barclay
> > Teledyne Brown Engineering
> >
> > -----Original Message-----
> > From: Fay John F Contr AAC/WMG [mailto:[log in to unmask]]
> > Sent: Thursday, July 18, 2002 5:02 PM
> > To: SISO - Run-Time Infrastructure and Communications Forum
> > Subject: Creating and Destroying Federations
> >
> >
> > Ladies and Gentlemen,
> >         Somewhere I got the impression that the HLA specifications require
> > that a federate try to create a federation before it joins it.  Now I am
> > trying to find it in the HLA specifications and cannot.  Does anybody out
> > there know whether HLA actually requires this?
> >         I do find in the Interface Specification (page 15, second
> > that the federation must exist before a federate can join it, but this is
> > different from saying that the federate must try to create it.  Any light
> > that anybody could shed on this would be appreciated.
> > John F. Fay
> > [log in to unmask]
> > ``Et verbum caro factum est, et habitavit in nobis; et vidimus gloriam

Keith Snively
Dynamic Animation Systems

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