Re: [v6ops] new draft: draft-yc-v6ops-solicited-ra-unicast

"Hemant Singh (shemant)" <> Tue, 21 July 2015 12:42 UTC

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From: "Hemant Singh (shemant)" <>
To: Mark Smith <>, Lorenzo Colitti <>
Thread-Topic: [v6ops] new draft: draft-yc-v6ops-solicited-ra-unicast
Date: Tue, 21 Jul 2015 12:42:16 +0000
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Subject: Re: [v6ops] new draft: draft-yc-v6ops-solicited-ra-unicast
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IPv6 ND and DHCPv6 do support randomizing sending of messages for the use case below.     Also, if a DSL modem is reset because its L2 headend reloaded, the hosts behind the modem will likely not reset.  Thus the number of hosts reset is less.


-----Original Message-----
From: v6ops [] On Behalf Of Mark Smith
Sent: Tuesday, July 21, 2015 5:51 AM
To: Lorenzo Colitti
Cc: v6ops list;
Subject: Re: [v6ops] new draft: draft-yc-v6ops-solicited-ra-unicast

Actually I've witnessed these sorts of events in recent times - when 1000s or 10s of 1000s of residential broadband subscribers come back on-line after the BRAS/BNG has booted either due to failure or maintenance, or the backhaul infrastructure between the BRAS/BNG and subscribers has failed and recovered.

Unicast RAs in the specific scenarios I've seen it in though may not have helped, as the subscribers were attached via individual PPPoE sessions, so multicasting a single RA to many/all of them efficiently might not be possible, unless there was some fancy hardware/firmware that meant the control plane didn't have to do it.

However, if single link/multi-access methods of attaching subscribers are used e.g., TR-101 N:1 VLAN, then solicited multicast RAs would help significantly reduce the number of multicast RSes from CPE during these events.