reachability issue with 3ffe:80a::/32 (PAIX IX segment)

[Stephen Stuart]

PAIX followed the same model it uses for v4 address space to get v6
address space - ISI provides micro-allocation services out of a block
from which they provide IXs with address space.

> 	i can think of couple of solutions:
> 	- an IX (say PAIX) gets an sTLA/pTLA.  the IX announces it to the world
> 	  based on normal prefix length (like /28 for pTLA).  the IX will
> 	  ensure connectivity between IX segments (so there will be no
> 	  reachability issue).

PAIX does not have any "interior" connectivity - that would amount to
having the IX compete with its customers for the carriage of traffic
in the wide area.

Also, PAIX owns no routers with which to make an aggregated
announcement (not that it couldn't be done, but it's not part of the
current model).

> 	- do not use global address on the IX segment.  I know some routers
> 	  cannot establish BGP4+ peers using linklocal address.

Possible.

> 	- define an address range for IX segments (like 3ffe:fff0::/28).
> 	  assign /48 out of it to IX (who assigns it is another question).
> 	  ask everyone to accept /48 (not just /28) for the prefix.
>
> 	- get 1 sTLA/pTLA prefix for each of the IX segment.  it is infeasible.

Given that the IX can't carry bits in the wide area, these wind up
being mostly the same option, and (I agree) infeasible.

Stephen