Re: 6MAN Adoption call on raft-chakrabarti-nordmark-6man-efficient-nd-04

[Mikael Abrahamsson <[e-mail]>]

On Fri, 20 Dec 2013, Mark ZZZ Smith wrote:

> Perhaps it might be better to treat the link as an NBMA subnet, and use 
> RFC2491 "IPv6 over Non-Broadcast Multiple Access (NBMA) networks" to 
> eliminate all multicasts (including ND, MLD and application), except 
> perhaps RAs with a flag that indicate the link is operating in NBMA 
> mode (with RA timers larger than defaults - IIRC, the max router age 
> value is 90 minutes, so unsolicited RAs can be around 30 minutes apart)?

I have had similar thoughts.

I would like to have mode where no discovery is done at all anymore, and 
in order to support legacy hosts, one way of doing that would be:

Legacy hosts see RAs with M=1, and they are handed address using DHCPv6 
IA_NA if they ask for it. They will not see any on-link prefix, and will 
send all traffic through the router. The router will install ND entry 
based on lifetime of the DHCPv6 IA_NA.

EAH will be able to do autoconfig by means of seeing an on-link /64 that 
is in a RA option that differs in a way that legacy hosts won't use it 
(preferrably also just unicasted to EAH by the router in response to RS). 
EAH use ARO to register their address just as in the draft.

If the router gets a packet to an address it doesn't have in the ND table, 
it just drops the packet. All traffic on the LAN is routed through the 
router, and optionally it can choose to send unicast redirects if it feels 
traffic is to hosts in the same L2 network.

-- 
Mikael Abrahamsson    email: [e-mail]