Re: [magma] Question about group ID ipv6 multicast addresses

Kunal Shah <> Mon, 20 September 2010 21:14 UTC

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From: Kunal Shah <>
To: Brian Haberman <>, "" <>
Date: Mon, 20 Sep 2010 17:13:58 -0400
Thread-Topic: [magma] Question about group ID ipv6 multicast addresses
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Subject: Re: [magma] Question about group ID ipv6 multicast addresses
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Hi Brian,

Thaks for your resonse. For group ID range 0x40000000 to 0x7FFFFFFF, can these group IDs be ever present in mcast addresses contained in MLD reports i.e Can customers have their STBs send out MLD joins for mcast addresses containing group IDs in this range??

If group ID ranges 0x00000001 to 0x3FFFFFFF and 0x40000000 to 0x7FFFFFFF cannot be present in mcast addresses coming in a MLD report, does this mean only the range 0x80000000 to 0xFFFFFFFF can be used with mcast addresses inside MLD reports??


-----Original Message-----
From: [] On Behalf Of Brian Haberman
Sent: Monday, September 20, 2010 1:59 PM
Subject: Re: [magma] Question about group ID ipv6 multicast addresses

On 9/17/10 5:14 PM, Kunal Shah wrote:
> Hi all,
> I was looking at the RFC 3307 and after reading section 4, I had the 
> following questions:
> 1. Permanent mcast addresses use Group Ids 0x00000001 to 0x3FFFFFFF .
> Does this mean this range of group IDS is reserved and cannot be used 
> with non permanent addresses??


> 2. Also can the group ID range 0x40000000 to 0x7FFFFFFF be used by 
> customers for their content channels??

That range is intended for use with IPv6 multicast addresses derived using RFC 3306.  You should note that the IANA considerations state that group IDs in this range are allocated based on Expert Review.  So, if the customer is sourcing well-known application data, then it may make sense to use this range.

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