On Fri, May 4, 2012 at 2:53 AM, Jeff Tantsura <jeff.tantsura@ericsson.com> wrote:
Hi,
All modern routers support mapping from IGMPv2 to PIM SSM, all static, some others thru DNS, etc
I am not sure what you mean here. To support SSM, you need IGMPv3. Most routers do support IGMPv3, but there is still a fair amount of legacy gear at various edges which doesn't. Regards Marshall
Regards, Jeff
On May 3, 2012, at 12:34 PM, "Nick Hilliard" <nick@foobar.org> wrote:
On 03/05/2012 21:00, Greg Shepherd wrote:
Sure, but GLOP predated SSM, and was really only an interim fix for the presumed need of mcast address assignments. GLOP only gives you a /24 for each ASN where SSM gives you a /8 for every unique unicast address you have along with vastly superior security and network simplicity.
SSM is indeed a lot simpler and better than GLOP in every conceivable way - except vendor support. It needs igmpv3 on all intermediate devices and SSM support on the client device. All major desktop operating systems now have SSM support (OS/X since 10.7/Lion), but there is still lots of older hardware which either doesn't support igmpv3 or else only supports it in a very primitive fashion. This can lead to Unexpected Behaviour in naive roll-outs.
Nick