All things related to multicast

[David Meyer <>]

> >     So the problem is that there are dense mode regions with
> >     "high bandwidth" streams, implying that flood and prune
> >     is the problem?
> 
> The most recent problem was purely SM domain sending about 1 Mbit/s
> of data. Some of our "research customers" have DM domains
> behind the SM connections - in my only feeling the border
> SM-DM is problem.

        So the border router is getting hit with 1 Mbit/s of
        data (if it unfortunatly has an interface on a LAN on that
        is on the distribution tree, or flood and prune), and 
        can't handle dropping that traffic? Is the problem router 
        cpu load?

> I am end user only and I would need the time to debug more deeply
> what I feel it is happening:
> 
> The SM domain mentioned above sends data.
> The other pure SM domains connected elsewhere behave as you say - join when
> they have users etc. When there is a small DM cloud inside of somebodies
> network and somebody ordinarily joins the group, he gets the data
> which is still OK -). The problem is, that the data flow to the DM domain
> never stops, even when there are no more any group members. The only
> thing, which helps is to disconnect the network for 20-30 mins, all
> times out and then it behaves for some time again - this helps sometimes, 
> when
> the SM-DM border is your direct neighbour, if it is more far away, there is 
> simply
> steady stream of data all the time.

        This sounds like a bug.

> We would like to debug this, we have at least three such networks. The 
> problem
> is, when this happens totally outside your management domain (e.g. "comodity
> Internet") you can`t do anything about it and just watch your "SM" 
> connection
> being totally useless as it was with DVMRP tunnels. Then the only solution 
> is 
> the Kevin`s
> one - admin scoping to simply restrict these data being forwarded.
> 

        Sure, that's a (the) standard answer. But then you have
        to coordinate the use of the admin scope inside I2. NASA
        (for one) has already said that this won't work for
        them, since they have the admin scoped space in use.

        

> >     BTW, what is a high bandwidth flow?
> 
> For us still 1 Mbit/s and more -).

        Ok.

        Dave