Re: ULAs [Re: draft-ietf-v6ops-ipv6-cpe-router-03.txt WGLC]

[Brian E Carpenter <brian.e.carpenter@gmail.com>]

Dan,

I'm fine with your suggested text.

Regards
   Brian

On 2010-01-06 09:16, Dan Wing wrote:
>> -----Original Message-----
>> From: Brian E Carpenter [mailto:brian.e.carpenter@gmail.com] 
>> Sent: Tuesday, January 05, 2010 11:48 AM
>> To: Dan Wing
>> Cc: 'Fred Baker'; v6ops@ops.ietf.org; kurtis@kurtis.pp.se; 
>> rbonica@juniper.net; draft-ietf-v6ops-ipv6-cpe-router@tools.ietf.org
>> Subject: ULAs [Re: draft-ietf-v6ops-ipv6-cpe-router-03.txt WGLC]
>>
>> On 2010-01-06 08:00, Dan Wing wrote:
>> ...
>>> Section 3.1 should additionally mention that an end-network
>>> IPv4 CPE that incorporates a NAT also incorporates a DHCPv4 
>>> server.  The inclusion of a DHCP server in the CPE is implied, 
>>> but should be explicitly stated.  The DHCP server in the CPE 
>>> allows the in-home network to be self-sufficient (for IP 
>>> addressing, if not naming).
>> Sure, for IPv4, you need DHCP, but...
>>
>>> This is relevant to IPv6 because, I have been told, ULAs
>>> provide a similar "LAN only" address.  This should be
>>> mentioned or a pointer to how hosts inside the home should
>>> use ULAs mentioned.  We do not want streaming between an
>>> in-home NAS and an in-home television to rely on the
>>> WAN link's availability.  This is mentioned (insufficiently)
>>> in Section 4.2 and some of the L-* requirements.
>> I don't understand what you're getting at here. Whether the
>> LAN uses a ULA prefix is orthogonal to whether it uses
>> DHCPv6.
> 
> Agreed; but I didn't say DHCPv6 was needed to assign ULAs (you did).
> 
>> It can be set up by RAs and SLAAC (or even manually,
>> but that's unlikely).
>>
>> I think the L-* requirements for ULAs are necessary and sufficient.
> 
> I agree the L-* requirements for ULAs are sufficient.
> 
> I am asking for more explanatory text about the value and purpose
> of ULAs (or a pointer to such explanatory text), in Section 3.2
> "IPv6 end-user network architecture", because Section 3.2's only
> mention of ULA is that the CE Router is a "ULA boundary".
> 
> We're in WGLC, so my suggested text for Section 3.2 is along
> the lines of something like this:
> 
>    Unique Local IPv6 Unicast Addresses (ULA) [RFC4193] are used
>    by hosts communicating within the End-user Network; this is
>    functionally similar to RFC1918 addresses used within an
>    IPv4 End-user Network.
> 
> and place that sentence immediately prior to the sentence in Section 
> 3.2 starting with "The IPv6 CE router defaults to acting as 
> the demarcation point ...".
> 
>> Despite the problems with RFC3484, I think the provision of a ULA
>> prefix by the CPE will bring about local streaming automatically.
>> That was certainly the intention behind ULAs.
> 
> I'm asking for text to provide motivation for the existing L-1 
> requirement (which reads "The IPv6 CE router MUST support ULA 
> addressing [RFC4193]").
> 
> -d
> 
>