Allocation of IP Addresses

Jim Browning jfbb at
Wed Mar 13 22:06:20 UTC 1996

I may be opening a can of worms, and if so, I believe it is one which needs 
to be opened.  If this topic has been beaten to death in the past, then I 
apologize, however as it is a rapidly evolving topic, it warrants repeated 
discussion and evaluation.  My fundamental questions are:

1.	Is InterNIC consistently applying objective criteria in its evaluation 
of requests for the allocation of IP address blocks?
2.	If so, what are the criteria?

that "allocation is based on the ISP's 3 - 6 month requirement and other 
information the InterNIC deems necessary".  There is no detail provided (in 
any document I have found) of what other information InterNIC deems to be 

I find an apparent conflict between established policy and its actual 
implementation on a day-to-day basis.  CIDR dictates that addresses should 
be aggregated into the largest blocks possible, and that the publishing of 
extraneous routes be eliminated.  In keeping with this, and because of 
often discussed operational considerations, the minimum size of blocks 
routed at the NAPs is growing larger and larger.  To ease participation at 
the national level, you must ensure to the fullest extent possible that 
your address space is routable as a single block.  In order to accomplish 
this, you must obtain either:

A.	a single allocation capable of supporting planned growth, or
B.	incremental allocations of *contiguous* blocks

InterNIC's current CIDR allocation practice does not support either of 
these options.  Due to the shortage of *available* IP addresses (there are 
of course millions of allocated but unused addresses floating around), 
InterNIC is using a "slow start" approach which provides incremental 
increases in total address space, with no guarantee that future increments 
will be contiguous.  This means that the only way to maintain efficient 
routing is to engage in repeated renumbering of customer addresses to 
consolidate into increasingly larger blocks.

How many times is it reasonable to ask a customer to renumber?  Once is 
certainly reasonable.  Twice is questionable.  More than that and I would 
suspect the customer would renumber all right, but as part of shifting to a 
different ISP.

The day to day implementation of policy by the InterNIC has increasingly 
critical impact on our industry, to the point of controlling who has the 
opportunity to succeed and who does not.  IMHO, it is imperative that:

1.	this function be performed in an understandable manner,
2.	objective criteria be consistently applied
3.	the criteria in use be publicly available, and
4.	there be defined mechanisms for the 'appeal' of decisions made in the 
processing of allocation requests.

Recent experience and observation leads me to conclude that these 
imperatives are perhaps not being met.  Am I all wet????
Jim Browning <jfbb at>
619/812-2860   Fax 619/812-2867

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