[152622] in North American Network Operators' Group
Re: mulcast assignments
daemon@ATHENA.MIT.EDU (Nick Hilliard)
Thu May 3 18:33:40 2012
X-Envelope-To: <nanog@nanog.org>
Date: Thu, 03 May 2012 23:32:56 +0100
From: Nick Hilliard <nick@foobar.org>
To: nanog@nanog.org
In-Reply-To: <CABFReBouo-p-zkG-am=3v0hwK=jKna_0ozHCBkZrsmpX5xqzNw@mail.gmail.com>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
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
