[c-nsp] Multicast on PPP

[Antonio Querubin]

On Mon, 26 Oct 2009, Gert Doering wrote:

> Hi,
>
> (top-posting really sucks).

For some reason alpine turned your post into an 'attachment' - not quite 
the same as top-posting.

> On Mon, Oct 26, 2009 at 09:26:23AM -1000, Antonio Querubin wrote:
>> You don't need PIM to do multicast over PPP.  Many dialup/terminal servers
>> that support multicast do so using some form of IGMP proxy.

> (But *if* you connect end users using PPP, you don't need an IGMP proxy
> on the ISP side - either the end user is directly connecting his machine
> to the PPP link, in which case it's "direct IGMP, no proxy", or the

I think that really depends on the type of equipment connecting the end 
user. Our access servers here aren't cisco equipment, do not run PIM, but 
do act like layer 3 devices.  Hence the only way for the access server to 
communicate group membership between the network and the end-user is to 
track the IGMP membership on all the PPP links and then proxy that on its 
ethernet interface.  On the other hand, for end-users who are sourcing 
multicast traffic, because our access servers do not run PIM, the sourced 
multicast traffic is just punted directly onto the ethernet.

Antonio Querubin
808-545-5282 x3003
e-mail/xmpp:  tony at lava.net