Re: [dhcwg] Next step(s) for draft-ietf-dhc-stable-privacy-addresses -> abandon work? / IA_NA applicability

[Fernando Gont <[e-mail]>]

On 04/02/2015 01:28 AM, Lorenzo Colitti wrote:
> On Thu, Apr 2, 2015 at 4:52 AM, Bernie Volz (volz) <[e-mail]
> <mailto:[e-mail]>> wrote:
> 
>     So, we're back to the question as to whether
>     draft-ietf-dhc-stable-privacy-addresses document is needed (and if
>     it is, whether it is Informational). If you really like the
>     algorithm and want to suggest to server implementers here is one you
>     can use, that's fine but it should be Informational then. I don't
>     see this as required to implement.
> 
> +1. draft-ietf-dhc-stable-privacy-addresses does not really provide much
> value on top of assigning addresses randomly. Address assignment via
> IA_NA is fundamentally stateful, so I don't see a lot of gain in making
> it "deterministic unpredictable" as opposed to "random unpredictable".

You get stability of the address, even in scenarios in which you have
multiple DHCPv6 servers, without the need of an additional protocol for
synchronizing the address leases database. An approach such as that
specified by this document is mentioned in RFC7031 itself. e.g.:

"  Also, the typical large address space (close to 2^64 addresses on /64
   prefixes expected to be available on most networks) may make managing
   address assignment significantly different from DHCPv4 failover.  In
   DHCPv4, it was not possible to use a hash or calculated technique to
   divide the significantly more limited address space, and therefore,
   much of the protocol that deals with pool balancing and rebalancing
   might not be necessary and can be done mathematically."

If you think the extra value is worth its implementation, you implement
it. If you don't, you don't.

-- 
Fernando Gont
SI6 Networks
e-mail: [e-mail]
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