Re: [6lo] Generation of IPv6 IIDs

[Erik Nordmark <[e-mail]>]

[Hit send too early]

On 7/23/14, 10:25 PM, Jonathan Hui (johui) wrote:
>> I think we should assume that those documents will be updated in the future to provide the option to work with other IIDs even if that comes with lower efficiency.
> Note that RFC 6282 already provides the option:
> - If the IID can be derived from MAC address, great.
> - If not, things will still work just with reduced efficiency.
>
> Section 10 of RFC 4944 also provides the same option, but has since been replaced by the encoding specified in RFC 6282.
>
> Also note that 802.15.4 interfaces have both a stable MAC address (EUI-64) and a locally-significant, dynamic MAC address (Short Address).  Many of the arguments against MAC-address-based IIDs may not apply when using Short Addresses.
>
> —
>

Good.

The issue I know about is in RFC 6775 which would fail to deliver errors 
to an ARO if the host doesn't have a link-local address with a 
EUI-64-based IID.

RFC 6775 (6lowpan-nd) makes the assumption that the host always has a 
link-local address configured with the EUI-64 of the host.
That assumption is used in section 6.5.2 to send errors back to hosts.
Note that we already know of a solution, which is local to the router 
implementation, which is already captured in section 9.7 in 
draft-chakrabarti-nordmark-6man-efficient-nd.

That doesn't prevent a host from having global addresses with other 
IIDs. In fact the host can have and use a link-local with a different 
IID as long as it will be able to receive the error packets sent to 
fe80::modified-EUI-64.

    Erik