Experiences with Comcast Ethernet/Transit service

Holmes,David A dholmes at mwdh2o.com
Mon Jan 4 21:56:20 UTC 2010

PIM-snooping is not in the MEF specs, but should be if multicast is to
work properly over a carrier's Ethernet service. Regardless of the
specs, RFPs and other user requirements for Ethernet services should
include a "must have" clause requiring PIM-snooping functionality. 

-----Original Message-----
From: Antonio Querubin [mailto:tony at lava.net] 
Sent: Monday, January 04, 2010 12:13 PM
To: Holmes,David A
Cc: Brandon Galbraith; nanog at nanog.org
Subject: RE: Experiences with Comcast Ethernet/Transit service

On Mon, 4 Jan 2010, Holmes,David A wrote:

> I do not know of Comcast's Ethernet services specifically, but a
> problem with carrier Ethernet services that are based upon the Metro 
> Ethernet Forum (MEF) is that PIM-snooping is not implemented for 
> multicast traffic. The absence of PIM-snooping results in the
> Ethernet service operating like a 1990's style Ethernet hub in which 
> (S,G) multicast packets are incorrectly flooded out all user ports.

Not implemented because it's not in the MEF specs or not implemented 
because of carrier operational practice?

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

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