Re: [Softwires] MAP-E question -- first prefix

[Tom Taylor <[e-mail]>]

OK, how about this for the complete paragraph:

    "By default, the MAP subnetwork identifier is the first subnetwork 
within the End-user IPv6 prefix (all bits set to zero). An alternative 
subnetwork value MAY be configured. All nodes within a MAP domain MUST 
be configured to use the same value of the subnetwork identifier."

I think that captures the intent. However, I see a possible difficulty: 
differing lengths of the End-user IPv6 prefix for different CEs. We have 
to add two conditions:

  -- the configured subnetwork identifier is at least
             64 - min (n + o)
bits long, where the minimization is taken over all FMRs in the domain

  -- the subnetwork identifier used with a given calculated End-user 
IPv6 prefix uses the right-most (64 - (n + o)) bits of the configured 
subnetwork identifier, where (n + o) is taken from the FMR used for the 
calculation.

Seems simpler just to restrict to the all-zeros value, but please comment.

Tom

On 09/04/2013 6:51 AM, Ole Troan wrote:
> Tom,
>
>> In Section 5.2 of -map-05, there is the paragraph:
>>
>> The MAP subnet ID is defined to be the first subnet (all bits set to
>>    zero).  Unless configured differently, a MAP node MUST reserve the
>>    first IPv6 prefix in an End-user IPv6 prefix for the purpose of MAP.
>>
>> Question: does the second sentence say anything different from the first one?
>>
>> Question: if the MAP node is configured differently, how will other nodes be able to synthesize its MAP IPv6 address from the FMR?
>
> all nodes within the domain must use the same subnet-id. perhaps we could make that clearer.
>
> cheers,
> Ole
>