----- Original Message -----
> From: Alexandru Petrescu <alexandru.petre...@gmail.com>
> To: sth...@nethelp.no
> Cc: ipv6@ietf.org
> Sent: Sunday, 21 October 2012 4:56 AM
> Subject: Re: Announcing Prefix Delegation extensions to ND 
> draft-kaiser-nd-pd-00.txt
> 
> Le 20/10/2012 18:36, sth...@nethelp.no a écrit :
>>>  There is also the question of availability of DHCP software on
>>>  smaller platforms which have no SIM card.  It may be easier to do
>>>  this with ND in smaller settings.
>> 
>>  The obvious conclusion to this argument is that a *lot* of DHCP
>>  functionality will be duplicated in ND. Is this where we want to go?
> 
> I guess yes, and vice-versa.
> 
>>  I'm coming from the DHCP side of the argument. In my world DHCP is
>>  needed because it gives you a single place to handle dynamic address
>>   allocation, *and* it ties in with all sorts of support & backend
>>  systems.
> 
> Well yes, when that backend is a fixed infrastructure with things
> planned, highly human assisted.  But in a dynamic yet simple network
> (without assistance of various backend) it's hard to use DHCP: a Relay
> can't 'discover' a Server,


Actually it can, as the destination address for the server the relay uses
can be the all-dhcp-serviers site-local (FF05:0:0:0:0:0:1:3) multicast
address. DHCPv6 uses multicast addresses where ever possible for these
sorts of scenario. Geographically distributed DHCPv6 servers can then be
a member of a multicast that spans locations across the network.


RFC3315, 5.1. Multicast Addresses

 DHCP makes use of the following multicast addresses:

      All_DHCP_Relay_Agents_and_Servers (FF02::1:2) A link-scoped
                  multicast address used by a client to communicate with
                  neighboring (i.e., on-link) relay agents and servers.
                  All servers and relay agents are members of this
                  multicast group.

      All_DHCP_Servers (FF05::1:3) A site-scoped multicast address used
                  by a relay agent to communicate with servers, either
                  because the relay agent wants to send messages to
                  all servers or because it does not know the unicast
                  addresses of the servers.  Note that in order for
                  a relay agent to use this address, it must have an
                  address of sufficient scope to be reachable by the
                  servers.  All servers within the site are members of
                  this multicast group.

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