Re: Hybrid TMLs

A TML with multiple transmission means, and the ability to properly 
assign them to FEs is also permitted.

Note that a multiple-transmission TML which includes the capability 
to work with the mandatory to implement TML is fully compliant with 
that TML.  What we are standardizing are bits on the wire, not the 
API or software modularization inside the implementation.  We should 
avoid specifying the implementation.  The only reason for having the 
TML service primitives defines is so that we can write multiple TML 
documents and be confident that different ones can be used.

Yours,
Joel M. Halpern

PS: Alex raises the useful question of versions of the PL / TML 
protocol.  I have written sound version negotiation algorithms 
before.  I have never seen the successfully used in practice.

At 12:25 PM 10/3/2006, Wang,Weiming wrote:
>Joel,
>
>Only a mandatory TML makes all our thoughts to separate PL from TML 
>much less meaning.  It's even not better and more restricted than to 
>mandate that "all TMLs be same in one NE" to solve the question. But 
>this is still quite restricted for ForCES deployments.
>
>I incline the scheme to keep one TML instance in any case, while 
>making a statement in the TML service primitves that a TML with 
>Hybrid TML media is allowed under condition that the hybrid TML 
>implmentation is responsible to provide services specified by the 
>TML service primitves document to PL uniformly.
>
>While at the same time, it may be of help for future use to assign 
>an TML id for an opened TML instance, even we only allow one TML 
>instance for one CE/FE.
>
>thanks,
>Weiming
>
>----- Original Message -----
>From: "Joel M. Halpern" <[email protected]
>
> > This is one of the reasons why there needs to be a mandatory to 
> implement TML.
> > I am inclined to observe that
> > Given the existence of at least one common TML, it is permitted for
> > the CE to simply use a TML that is common across all FEs.
> > A CE which has support for multiple TMLs, and which can manage the
> > selection and management issues of using such (including, if used,
> > multicast) is free to choose to use multiple TMLs to speak to
> > different FEs in the NE.
> >
> > I.e. a single TML works, but we have no reason to prohibit multiple
> > TMLs, if someone builds a CE that can do it.
> >
> > Yours,
> > Joel Halpern
> >
> > At 11:23 AM 10/3/2006, Wang,Weiming wrote:
> > >Hi,
> > >
> > >When I'm considering the TML service primitive, I come upon a
> > >question on the TML instances.
> > >
> > >Considering a case with one CE and multiple FEs,  it is possible FEs
> > >may use different TML media for ForCES protocol transportation. This
> > >actually implies the CE have to support more than one TML instances,
> > >or the CE TML must be an all in one TML, with different TML media
> > >supported by one TML layer.
> > >
> > >There are several questions here:
> > >1. Shall our charter support different TML media in one ForCES NE?
> > >2. If yes, then what scheme shall we adopt, multiple TML instances
> > >or allowing a hybrid TML? Or, do we have other alternatives? I just
> > >can see questions for either of the schemes.
> > >
> > >Thanks a lot for any thoughts.
> > >
> > >Weiming