What does it mean to be issued an IP address block? (Re: Newbie Questions: How-to monitor/control unauthorized uses of our IPs and DNS zones?)

John Curran jcurran at arin.net
Fri Aug 20 02:30:30 UTC 2021

Folks - 

(I’ve changed the subject to keep this part of the thread separate - but it would be nice if others more clueful than myself in such matters addressed Pirawat’s actual questions regarding DNS zone and redirection monitoring…) 

Regarding IP address blocks, I’m going to provide the simple view that ARIN takes on this, recognizing that we’re not dealing in an area that is clearly established and thus others may have their own views.

To answer what it means to “own an IP address block”, it is first necessary to make some assumption about what an “IP address block” really _is_ – in the case of ARIN, we consider an IP address block to be an entry in the ARIN registry database, and we issue blocks by granting of specific rights to those entries to the resource holder.

When you are issued a block, your organization is associated in the database with that particular IP block entry and you receive a set of contractual rights (right to be exclusively associated with, right to use/update it in the database, and right to transfer in accordance with policy) as per the ARIN RSA.   If you “own” an IP address block then you’ve got that bundle of contractual rights that you control, but they are not exclusive - those same entries are subject to other rights - such community’s right to publish portions publicly, to add fields (e.g. abuse contact), etc. that ARIN administers on behalf of the community.   (ARIN also works with the other RIRs so that you uniqueness in the ARIN registry translates to uniqueness in the overall Internet number registry system.) 

ARIN is the successor operator of the registry database for the region, and we also recognize that some organizations have obtained assignments of similar bundles of rights via implied contract under which recipients desired to cooperate in (and gain the benefits of coordination from) the Internet Number Registry system in the period before ARIN’s administration of the database.  ARIN provides such parties (“legacy resource holders”) and their legal successors with the opportunity to formalize their rights (if they wish) via entry into ARIN's registration services agreement.

We have many cases where the rights to specific blocks have been treated as “property” of an estate during bankruptcy or probate proceedings, and this should be no surprise - contractual rights have value and as such can be considered part of an estate and transferred accordingly. It is worth noting that ARIN spends a bit of time engaging to make sure that community policy is followed regarding such transfers and to date we have never had to update ARIN’s database without adherence to our policies and entry into an RSA by the recipient.  

If you think that the “IP address blocks” that you were issued are reflected by the listing of your organization on that entry in the ARIN database, then all of the description above makes sense.   There are some other theories out there about what constitutes an “IP address block” –  I’ve heard all manner of theories including 'rights to integers’, 'reservations in routing tables’, and pretty much everything in between.  Diversity of views is a wonderful thing, but I would advise some caution if someone offers to sell such ephemerally defined “IP address blocks” to you – good luck, but remember that they don’t involve the ARIN database or its entries and one might find them somewhat lacking as a result...

Best wishes (and stay safe!)

John Curran
President and CEO
American Registry for Internet Numbers

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