"portability" of IP Addresses
alan at mindvision.com
Fri Jan 31 03:30:42 UTC 1997
I am curious for perspectives on the use of non portable
IP addresses for multi-homing.
Can a provider forbid their customer from announcing allocated
networks to another provider?
Assume the following situation:
ISP A gets customer C to sign an agreement for service. ISP A
allocates network A.B.C.0/20 to customer C. A.B.C.0/20 is a
subnet of CIDR block A.B.0.0/16, allocated to ISP A by our friends
at the InterNIC as a non-portable address space.
It should be obvious that customer C is locked in for Y years, and
is paying D dollars per year.
Ok. With me so far? :-)
So, customer C goes to ISP B, and says, I'd like to buy service
from you, and announce network A.B.C.0/20 to you.
Customer C informs ISP A, for niceties, and ISP A informs them
that they cannot do this. If Customer C wants to announce routes
to both ISP A and ISP B they must renumber. (source of IP
Addresses for renumbering is left to your imagination, ISP A, B, or
direct from InterNIC.)
Can ISP A enforce this decree? I realize it depends upon the
contract, but let's assume the contract doesn't specify.
I would think that ISP A would not mind Customer C announcing the
network to ISP B, but would make it clear that if Customer C stops
the relationship with ISP A, then ISP A would reclaim the address
Is this intelligent use of IP Address space, draconian practices
to discourage multihoming, or probably a miscommunication?
email: alan at mindvision.com.
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