Is it permissible to advertise number resources allocated by one RIR to a ISP in a region governed by a different RIR? Practical?

Wed Feb 9 21:24:28 UTC 2011

"Crooks, Sam" <Sam.Crooks at experian.com> writes:

> Is it permissible, from a policy perspective, for a multi-homed end user
> to announce the numbering resource allocation received from one RIR (for
> discussion purposes, let's say ARIN) to upstream service providers in a
> different region (for example, in the RIPE region)?

Yes.

> Is it feasible from a practical perspective?

Sure, people advertise prefixes allocated by ARIN in RIPE and APNIC
territory all the time.  If that didn't work, multinational networks
wouldn't work so well would they?

> I've looked through IANA and ARIN policy and can't find anything which
> covers such a scenario.  I have seen some things about transferring
> number resources from one RIR to another RIR, which is similar, but not
> exactly the same.

That's because the Internet is global in scope.

> Suppose you are a large global enterprise, truly globalized in practice,
> not in mere name, and performance concerns aside, you provide failover
> for Internet access of enterprise users in one region by failing over to
> internet access in a different region.  Since you probably are using
> 10/8 addressing within your network and you NAT the private IPv4
> addresses to a public IPv4 address before sending the traffic on.., so
> this works.   Given lack of NAT66, and the best practice IPv6 numbering
> which is purported to use globally routable IPv6 addresses within your
> enterprise network, the achievable way to accomplish the same use
> possible today in IPv4 would seem to be to advertise the IPv6 addressing
> from one RIR to a ISP in a region governed by a different RIR (or LIR). 

I have worked for multiple companies where this (or something similar,
like anycast, multiple discrete networks, or even international pipes)
happens.  No problemo.

-r