|
FAST Protocol
< Previous Next >
Re: Fast SCP
Greg Orsini / Cameron Systems <>
31 Jul 2008 11:44AM ETHanno,
There is no way to know how long the message is without the correct template, so a new message with an unknown or 'extended' template can't be fully decoded (a result of the decision to not include a message length in FAST or SCP).
Perhaps an optional length for messages requiring a new template would maintain the integrity of the transport layer without affecting the message contents.
Then you could create a revised template (instead of 7 it would 7.1?) that could have additional fields that would be ignored until you get a hold of the new template.
Greg.
> Hanno, this is an interesting problem.
>
> The short answer is no. There is no way for the receiver to detect that
> there is another field in the message. As you mention, you could put a
> placeholder into the template, maybe an optional field at the end of the
> template. This would maybe work in some instances, but you would be
> restricted in choice of operator etc.
>
> We did discuss this some when we were updating the spec from 1.0 to 1.1,
> but nothing came out of that discussion if I recall correctly.
>
> It's worth discussing again, though. Anyone has ideas on this?
>
> /Rolf
>
> > Rolf,
> >
> > I have a related question. Is there a way to send a new message
> > without having sent a new template definition, i.e. if I add a field
> > to my message, is there a way for the receiver to ignore that new
> > field until he receives a new template definition from me, perhaps by
> > appending it to the end of my message and having a placeholder in my
> > initial template definition? Or is it a strict requirement to always
> > send a new template definition prior to sending a message for it.
> >
> > Thanks, Hanno.
Fast SCP Dimitry London / Morgan Stanley 30 Jul 2008 10:16PM ET Re: Fast SCP David Rosenborg / Pantor Engineering AB 31 Jul 2008 3:28AM ET Re: Fast SCP Rolf Andersson / Pantor Engineering 31 Jul 2008 6:17AM ET Re: Fast SCP Rolf Andersson / Pantor Engineering 31 Jul 2008 9:05AM ET Re: Fast SCP Hanno Klein / Deutsche Börse Systems 31 Jul 2008 10:06AM ET Re: Fast SCP Rolf Andersson / Pantor Engineering 31 Jul 2008 10:15AM ET Re: Fast SCP
Greg Orsini / Cameron Systems 31 Jul 2008 11:44AM ET Re: Fast SCP Rolf Andersson / Pantor Engineering 1 Aug 2008 2:06AM ET Re: Fast SCP Rolf Andersson / Pantor Engineering 1 Aug 2008 2:39AM ET Re: Fast SCP Rolf Andersson / Pantor Engineering 1 Aug 2008 3:13AM ET Re: Fast SCP Hanno Klein / Deutsche Börse Systems 1 Aug 2008 3:33AM ET Re: Fast SCP Rolf Andersson / Pantor Engineering 1 Aug 2008 3:57AM ET Re: Fast SCP Rolf Andersson / Pantor Engineering 1 Aug 2008 4:10AM ET Re: Fast SCP Rolf Andersson / Pantor Engineering 1 Aug 2008 3:06AM ET Re: Fast SCP David Rosenborg / Pantor Engineering AB 1 Aug 2008 6:28AM ET Re: Fast SCP Jacob Northey / The LaSalle Technology Group 1 Aug 2008 8:21AM ET Re: Fast SCP David Rosenborg / Pantor Engineering AB 1 Aug 2008 9:33AM ET Re: Fast SCP Greg Orsini / Cameron Systems 1 Aug 2008 10:01AM ET Re: Fast SCP David Rosenborg / Pantor Engineering AB 1 Aug 2008 10:16AM ET Re: Fast SCP Greg Orsini / Orc Software w/CameronFIX 1 Aug 2008 10:32AM ET Re: Fast SCP David Rosenborg / Pantor Engineering AB 1 Aug 2008 10:58AM ET Re: Fast SCP Jean-Marie Sulmont / RTS 31 Jul 2008 10:19AM ET Re: Fast SCP Jean-Marie Sulmont / RTS 31 Jul 2008 10:41AM ET Re: Fast SCP David Rosenborg / Pantor Engineering AB 31 Jul 2008 11:10AM ET Re: Fast SCP Dimitry London / Morgan Stanley 7 Aug 2008 10:53PM ET
|
