Hi,

Op 3 jun. 2013, om 00:26 heeft Brian E Carpenter <[email protected]> 
het volgende geschreven:
> On 03/06/2013 10:06, Steinar H. Gunderson wrote:
>> 2013/6/2 Brian E Carpenter <[email protected]>:
>>>> I'm not sure about other switches, but for the Catalyst 3750/3750G, it
>>>> means some quirks with IPv6 ACLs.  The 3750/3750D can do ACLs on full
>>>> /128's, but only if the lower 64 bits are EUI64.
>>> Huh? How can it possibly know that? (see draft-ietf-6man-ug)
>> 
>> Presumably he means that the middle bits are ff:fe.
> 
> And the UG bits are 10. But none of that proves that the identifier
> is EUI64. It only proves that it *might* be EUI64.

I think I understand the following: the 'optimisation' that Cisco makes here is 
that *if* the middle bits are ff:fe and UG is 10, then they accept an ACL with 
that address, and they don't actually store the 'known' bits but use the space 
to store other information in the TCAM. It would have to reject any ACL that 
tries to match on the full 128 bits where those specific bits are not 10 and 
ff:fe.

Darren: am I understanding this correctly?

Cheers,
Sander

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