All things related to multicast

[Hitoshi Asaeda <>]

Hi Frank,

> 1. If I am to understand "distributed agents" as discrete unique  
> servers, how many do you estimate would be needed to support  
> worldwide coverage?

It is possible to set up a single agent in the start up phase. In this
case, the agent system (with one agent) simply behaves as a central
web server.
If we set up a large number of agents, these agents communicate each
other to synchronize the session information (as a replication
manner). This would give its robustness and better performance.
And also, using multiple agents enable to set up some policy
definition, since "your" agent can maintain "your site-local" session
information without synchronization, as well as the global session
information that is shared with other agents.

Well, we've also measured the performance for session information
registration on OpenDHT over PlanetLab. It just took a few
seconds for replicate the global session information with all
agents.

> 2. On a practical level, as many of us only stream a few channels, it  
> would not make sense for each of us to set up a server, even assuming  
> we have the resources. So, would there be centralized locations,  
> sponsored by different groups, where we could be authorized to send  
> our program listings?

It is possible to use a single server, of course. But just using
single server does not address many issues. For example, how make it
open access for session information registration? Session information
registration may be restricted in some cases.
One of the problems in use of SAP is the difficulties of such security
or policy management, no? Well, using multiple and well-managed agents
is not only for giving security consideration. As of above,
performance and robustness would be the important advantages. But
this kind of security consideration and policy management would be
also focused on.

> 3. Any way to link this system to an easy "click-and-receive"  
> interface like VLC's SAPs?

From an end user, CR is just looks like a web system. The user does
not need to know the agents, and hence helper applications can be
used.

> Sorry if I have misunderstood any of the concepts.

I'm very happy if you feel our proposal would be beneficial for all
multicasters. :)

Thanks,
--
Hitoshi Asaeda