Re: Simple Multicast - building a case for a BOF or WG

[Mikhail Smirnov <smirnow@fokus.gmd.de>]

Hi,

On Sun May  9 19:46:40 1999 David R. Cheriton wrote:
<...>
>   So, besides large-scale single-source applications such as Internet TV,
> distance learning and multicast data delivery, what are the compelling
> applications?  After working with multicast for the past 18 years, and on
> EXPRESS for the past 3 years with Hugh, I'm not seeing any compelling
> applications that arent quite implementable with single-source multicast.
> Please tell me what I am missing!

I think that "large scale, economically compelling" applications which 
demand [deployable] IP multicast are numerous in the area known as
Information Systems (IS). ISs carry mission critical tasks in managing
[global] enterprises. More and more IS developers are speaking object
oriented [CORBA] language. In *their* vision application is an object
which could require service from any other object worldwide. Right now
they use TCP/IP (multiple unicasts) but they are far from being happy
about this - they want [reliable and highly scalable] multicast to be
absolutely transparent to their OO world. 
ISs requirement then: quasi-static shared multicast distribution tree with
extremely low (--> zero) latency of multicast address allocation and
extremely high dynamics of multicast groups (i.e. extremely short 
multicast sessions). Note, that in fact almost every new group is a
subgroup of a meta group (hence - quasi-static trees), and potentially
any object of a meta group could become a sender (hence - shared trees).
Note that CORBA-enabled hosts could be populated by thousands of active 
objects (hence - dynamic address allocation is needed, not a block 
reservation).

Regards

Michael