Re: v6 subnet size for DSL & leased line customers

Donald Stahl wrote:
> 
>> in real life; people still find it necessary to
carve up their
>> aggregates and announce more-specifics in strategic
directions. I
>> would suggest that not *all* observed instances of
such deaggregation
>> are due to operator ignorance 
> There's a big difference between deaggregating a couple
of bits for TE
> purposes and announcing 64 /24's from your /18 
> 
> We need to decide what's acceptable as a community and
then enforce it
> as a community. If someone starts announcing dozens of
prefixes in v6
> then they get blocked they either get blocked or they
get a filter that
> restricts them to their covering route (or blocks them
if they don't
> have it).

On this note: In the v6 world when multihoming, what size
network block is the minimum recommended allocation? In the
v4 Internet, most major networks I've seen do not accept
anything longer than /24 and this is what is allocated to
customers with their own AS when multihoming regardless of
the usage of the /24. I'm just curious if this is currently
outlined somewhere already as what was decided. Are we going
to see /64's, /56's or /48's polluting the v6 routing table
just as /24's are today on the v4 table? I understand most
of that pollution is not because of multihoming, but rather
TE or negligence/lack of clue. With the advent of 32 bit
ASN's, this could possibly become a concern however... that
and people trying to do TE with their v6 space as they did
with v4. I agree with the above reply that this needs to be
ironed out as a community and was curious how multihoming
customer networks fit into this equation.

-- 

Vinny Abello
Network Engineer
vinnytellurian.com
(973)940-6100 (NOC)
PGP Key Fingerprint: 3BC5 9A48 FC78 03D3 82E0  E935 5325
FBCB 0100 977A

Tellurian Networks - The Ultimate Internet Connection
http://www.tellurian.com
(888)TELLURIAN

"There is no objective reality. Only that which is
measured exists.
We construct reality, and only in the moment of measurement
or observation." -- Niels Bohr

I'm glad to see more people are starting to look at this
issue.  If you are just now beginning to look into the IPv6
Multihoming issue I would start with reading a few strings
on IETF, NANOG and ARIN mail lists and the following
document posted 2 years ago at: http://www.nro.org/documents/pdf/MultihomeIPv6procon.pdf


Decisions need to be made soon and all kinds of policy can
effect that.  Their are dueling issues at hand on this
matter and we need to find a balance.  Traffic Engineering
and Multihoming is an Engineering requirement.  Not
exploding the tables is also a requirement.  Right now
policy only inadvertently supports PI to be used for
Multihoming and policy inadvertently does not support TE or
Multihoming.  Not permitting TE or Multihoming on large
networks is not going to be accepted by the large networks
as an answer.  So it would be a "good thing" if
our community could work out a balance that permits TE and
Multihoming on a managed scale.  Otherwise those networks
will just start doing whatever they want or need.

Cheers!
Marla

-----Original Message-----
From: owner-nanogmerit.edu [mailto:owner-nanogmerit.edu] On Behalf Of Vinny Abello
Sent: Wednesday, January 02, 2008 10:53 AM
To: Donald Stahl
Cc: Joe Abley; Iljitsch van Beijnum; Christopher Morrow;
NANOG list
Subject: Re: v6 subnet size for DSL & leased line
customers


Donald Stahl wrote:
>
>> in real life; people still find it necessary to
carve up their
>> aggregates and announce more-specifics in strategic
directions. I
>> would suggest that not *all* observed instances of
such deaggregation
>> are due to operator ignorance
> There's a big difference between deaggregating a couple
of bits for TE
> purposes and announcing 64 /24's from your /18 
>
> We need to decide what's acceptable as a community and
then enforce it
> as a community. If someone starts announcing dozens of
prefixes in v6
> then they get blocked they either get blocked or they
get a filter
> that restricts them to their covering route (or blocks
them if they
> don't have it).

On this note: In the v6 world when multihoming, what size
network block is the minimum recommended allocation? In the
v4 Internet, most major networks I've seen do not accept
anything longer than /24 and this is what is allocated to
customers with their own AS when multihoming regardless of
the usage of the /24. I'm just curious if this is currently
outlined somewhere already as what was decided. Are we going
to see /64's, /56's or /48's polluting the v6 routing table
just as /24's are today on the v4 table? I understand most
of that pollution is not because of multihoming, but rather
TE or negligence/lack of clue. With the advent of 32 bit
ASN's, this could possibly become a concern however... that
and people trying to do TE with their v6 space as they did
with v4. I agree with the above reply that this needs to be
ironed out as a community and was curious how multihoming
customer networks fit into this equation.

--

Vinny Abello
Network Engineer
vinnytellurian.com
(973)940-6100 (NOC)
PGP Key Fingerprint: 3BC5 9A48 FC78 03D3 82E0  E935 5325
FBCB 0100 977A

Tellurian Networks - The Ultimate Internet Connection http://www.tellurian.com
(888)TELLURIAN

"There is no objective reality. Only that which is
measured exists.
We construct reality, and only in the moment of measurement
or observation." -- Niels Bohr