Re: disagreement on which OS should change

[Fernando Gont <[e-mail]>]

On 27/4/19 09:54, Brian Carpenter wrote:
> I don't understand this discussion. 

Sigh.. I thought it was just me & insufficient amounts of caffeine :-)


> LL addresses exist in the absence of
> any routers and are created spontaneously by hosts with no external
> inputs. Therefore, there is no such thing as an identity for a link,
> there is only an interface identifier which is strictly local to the
> host. 

The IID ends up being meaningful link-wise -- that's why there's (at
least in theory) DAD for LLs.



> Even in a point to point case, there is no reason that the two
> hosts would agree about the link's identity.

In fact, if one assumes /64, and selects non-zero bits for the rest of
the prefix, then either you have to come up with a subnet-id
election/disovery mechanism/algorithm, or you just can use the LLs,
since most other nodes would probably be considered off-link.

An alternative is to introduce an onlink route for fe80::/10... at which
point the rest of the bits become, in practice, part of the IID.

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