I see very often that customers in the US send morespecs all
over the place, deaggregate whole /14s or such scary crap,
ask us to accept random stuff out of 4/8 and 8/8 (L3 space)
by example.
I am practically asking what is (if any) the normal way for
any of this. I am working by the principle that not everything
I could do I should do, especially not right away. Is there
any accepted procedure / policy for anyone to a) announce and
b) accept (the transit supplier) and have that sanctioned
formally? Maybe nobody cares, then tell me.
Coming from Europe where pretty much everyone is RIPE LIR and
has its own /21 at the least I might not see the problem that
allegedly some (many) US ISPs do have. Enlighten me.
(And, no, I do not fall for the urban legend that RIPE or ARIN
are by default evil, clearly not. I do have real- life
experience that whenever you can rightfully justify even large
IP assignments you do get it.)
I see very often that customers in the US send morespecs all
over the place, deaggregate whole /14s or such scary crap,
ask us to accept random stuff out of 4/8 and 8/8 (L3 space)
by example.
I am practically asking what is (if any) the normal way for
any of this. I am working by the principle that not everything
I could do I should do, especially not right away. Is there
any accepted procedure / policy for anyone to a) announce and
b) accept (the transit supplier) and have that sanctioned
formally? Maybe nobody cares, then tell me.
There is a lot of "nobody cares", but I'm not sure that accounts for everything you see.
Can you give us some examples so us "dumb Americans" can more precisely explain the problem?
Coming from Europe where pretty much everyone is RIPE LIR and
has its own /21 at the least I might not see the problem that
allegedly some (many) US ISPs do have. Enlighten me.
(And, no, I do not fall for the urban legend that RIPE or ARIN
are by default evil, clearly not. I do have real- life
experience that whenever you can rightfully justify even large
IP assignments you do get it.)
Can you give us some examples so us "dumb Americans" can more
precisely explain the problem?
When a random customer (content hoster) asks you to accept
something out of 8/8 that is Level(3) space, and there is no
route at this moment in the routing table, do you accept it,
or does Level(3) have some fancy written formal process and
they get approval to do it, etc.?
In Europe we would tell the customer this ain't gonna happen,
as we would re- announce blocks out of 'foreign' LIR allocations
and that is a no-go, unless the holder of that allocations
acks that.
What if you try to justify small assignments?
I have done numerous /24 or /23 requests and my first hit
approval rate is probably 90+ percent. RIPE only, I do not
know ARIN.
> Can you give us some examples so us "dumb Americans" can more
> precisely explain the problem?
He did.
When a random customer (content hoster) asks you to accept
something out of 8/8 that is Level(3) space, and there is no
route at this moment in the routing table, do you accept it,
or does Level(3) have some fancy written formal process and
they get approval to do it, etc.?
In Europe we would tell the customer this ain't gonna happen,
as we would re- announce blocks out of 'foreign' LIR allocations
and that is a no-go, unless the holder of that allocations
acks that.
If there is clear expression of intent (SWIP/RWHOIS delegation)
and the customer is multihoming then it is easy. If the customer
isn't multihoming, verification of space portability is needed.
If no clear published intent, allocation verification needs to
be furnished preferably by the other provider.
Can you give us some examples so us "dumb Americans" can more
precisely explain the problem?
When a random customer (content hoster) asks you to accept
something out of 8/8 that is Level(3) space, and there is no
route at this moment in the routing table, do you accept it,
or does Level(3) have some fancy written formal process and
they get approval to do it, etc.?
In Europe we would tell the customer this ain't gonna happen,
as we would re- announce blocks out of 'foreign' LIR allocations
and that is a no-go, unless the holder of that allocations
acks that.
Here, it seems that some ISPs will accept foreign PA routes* _as long as the customer is still connected to that other provider_. Some won't under any circumstances. The remainder aren't filtering their downstreams and have no clue what they are providing transit for (i.e. it's the customer's job to get it right).
If you do decide to accept a foreign PA route, you need to be very careful to point out to the customer (a) some people will filter your route for being too long and send their traffic to the owning provider, and (b) if the other provider doesn't announce the longer prefix in addition to their aggregate, anyone who accepts the longer route will send traffic only to you due to longest match. Both cases can result in suboptimal routing.
The correct** solution is to help them become an LIR, assuming they qualify.
S
* meaning a route for part of another ISP's aggregate
** for some values of "correct"
Stephen Sprunk "Stupid people surround themselves with smart
CCIE #3723 people. Smart people surround themselves with
K5SSS smart people who disagree with them." --Aaron Sorkin
Initial instinct has to just be 'yuck', but in the interest of getting
the job done, I'd look at :
- how is it registered ? Are your customer mentioned ?
- is it already a prefix which is announced seperately from the rest of
the aggregated block ?
- if the customer wants to multihome, have they even considered PI ?
- are the customer happy for you to talk to the aggregating company ?
are you happy to talk to them ?
- it's still 'yuck'.
Frankly, if the customer is multihomed, then, it might be preferable for
them
to go direct to ARIN for an end-user assignment. These are now available as
small as a /22 since the adoption of policy 2002-3.
I would expect some sort of confirmation that Level3 has allocated the block to them - if there is no swip or RADB object, the customer should request that Level3 create one (or both). If Level3 cannot do either (unlikely) I'd request direct contact from Level3 confirming the allocation.
Btw, I hope you folks would defer to Level(3)'s reannouncement
policy, which is very clear in their AS object located within RIPE's
IRR, which reads:
If you are a provider who has been asked to route a
more-specific network block that is part of 4.0.0.0/8,
please ask your customer to contact Level 3 to obtain
a new network block.
Level 3 will not accept advertisements for any networks
that are part of 4.0.0.0/8 from any non-customer peer.
So, if you want to do what's "right", tell your customer to go
talk with Level(3), so they can renumber into IP space that would be
permitted to be announced more specifically. If anybody wants to see
the comments in their as object, just look at http://www.onesc.net/communities/as3356 it's very clear.
