V peers with X at a number of points. V and X announce the same routes
to each other at all these points.
V and X are also members of the CIX and are announcing routes to the CIX
router. X announces different routes to the CIX router than they
announce directly to peer V because Y pays X to specifically announce
Y's routes at the CIX.
Should V be unhappy with X's inconsistent route announcements? Should
X's announcement via the CIX be consistent with their announcements at
the other points V and X meet?
o yes, because the CIX is a peering point, though router-based (this
in itself may be worth a different discussion).
o no, because in realty V and X each are paying customers of the CIX,
and the CIX is merely announcing their customers' routes to each
other.
My apologies for opening an operational issue in an inappropriate forum.
randy
V peers with X at a number of points. V and X announce the same routes
to each other at all these points.
V and X are also members of the CIX and are announcing routes to the CIX
router. X announces different routes to the CIX router than they
announce directly to peer V because Y pays X to specifically announce
Y's routes at the CIX.
Where did Y come from? A Nike commercial? Y ask Y? 
Personally, I
find numbers easier to follow than letters in these examples, don't U? Is
the multihomed case W?
Slightly more seriously, a little more detail would help.
Is Y's space independent from both X and V? I could see V being unhappy if
X is advertising a more specific route in V's space, although this could be
reasonable if coordinated.
Does Y advertise its routes at any points other than through X? Does Y
have a distinct ASN?
If Y is being advertised as part of X's AS, that seems to be a valid local
peering policy.
Should V be unhappy with X's inconsistent route announcements? Should
X's announcement via the CIX be consistent with their announcements at
the other points V and X meet?
o yes, because the CIX is a peering point, though router-based (this
in itself may be worth a different discussion).
o no, because in realty V and X each are paying customers of the CIX,
and the CIX is merely announcing their customers' routes to each
other.
Is the underlying issue that someone should announce all routes at an
exchange point? It sounds as if V is complaining because X is selling
transit to Y.
Howard
Actually, sounds like a political issue to me.
What do your peering contracts say?
if the the cix relationship is mutual purchase of transit from a third
party, then V and X have no contractual relationship.
randy
To review the bidding, the following relationships exist?
Contractual V X Y CIX
V - no no yes
X no - yes yes
Y no yes - no
Advertises V X Y CIX
V - yes no yes
X no - yes yes
Y no yes - yes
V peers with X at a number of points. V and X announce the same routes
to each other at all these points.
V and X are also members of the CIX and are announcing routes to the CIX
router. X announces different routes to the CIX router than they
announce directly to peer V because Y pays X to specifically announce
Y's routes at the CIX.
Should V be unhappy with X's inconsistent route announcements? Should
X's announcement via the CIX be consistent with their announcements at
the other points V and X meet?
o yes, because the CIX is a peering point, though router-based (this
in itself may be worth a different discussion).
o no, because in realty V and X each are paying customers of the CIX,
and the CIX is merely announcing their customers' routes to each
other.
Please note the evidently subtle point that, in this last case, any peering
contract between V and X is not really applicable because this is not a
peering relationship. I.e. surely any peering contract between V and X
would not place terms or conditions on each other's possible relationship
to, for example, MCI.
randy
I suppose the issue comes down to whether one considers the CIX
relationship to be one of transit provider or if it is considered an
exchange point.
This is is the crux of the question I meant to be posing.
Again, this is a political issue, and should probably be worked out between
the two providers involved (hopefully through operational people and not
lawyers though ;).
It is also a technical issue, as there are technical reasons why consistent
routing announcements are usually specified, whether the CIX is an exchange
or a for-fee transit provider is partially a technical judgement, ...
The two providers did, for the moment, work it out at the engineering level.
But we agreed the issue was interesting and the answer not obvious.
randy
What, randy. You mean you weren't _clear_ in your initial inquiry?
No! Say it isn't so!
Cheers,
-- jra
Actually, sounds like a political issue to me.
What do your peering contracts say?
Justin W. Newton