Draft internic ip allocation doc

Mark Kosters markk at internic.net
Tue May 16 17:23:19 UTC 1995


As you know, our past unwritten policy was to only dole out ip space
to isps that were directly connected to major routing exchange points,
or those whose requirements exceeded their upstream providers desire
to allocate from their own space. After numerous discussions, we have
developed the following document to be our new procedure for allocating space.
We hope there is consensus amongst us.

If there is not too much negative commentary, the InterNIC would like 
to start allocating space in terms of this document very soon. Also, the 
document below is an interim measure in lieu of the rfc1466bis document
which is under construction.

Mark and Kim



The InterNIC Registry, under the authority of the Internet Assigned Numbers
Authority, allocates blocks of address space to Internet Service
Providers (ISP) for the purpose of using that space with their customers.

ISPs and others not located in the InterNIC's geographical area of
responsibility should contact the appropriate Regional Registry for
information on how to obtain IP addresses.  The following is a list
of Regional Registries and National NICs that have authority to allocate
IP addresses:

Other Regional Registries
  RIPE NCC  (European Registry)  hostmaster at ripe.net
  APNIC (Asia Pacific Registry)  hostmaster at apnic.net

InterNIC Delegated Registries within the Americas
  CA*net (Canadian NIC)    ipregist at canet.ca
  RNP (Brazilian Registry) gomide at fapq.fapesp.br

To aid in the utilization of Classless Interdomain Routing (CIDR), ISPs
are encouraged to request address space from their upstream provider,
it must be noted that the upstream provider maintains control of the
allocated block unless explicitly and contractually stated otherwise.
However, CIDR blocks may be allocated directly from the InterNIC if

The following guidelines have been established in an attempt to allocate
address space to ISPs in a way that is fair but will address the issues
of router table growth and IP address preservation.  This document
also details procedures that must be followed by ALL ISPs receiving
address space which is then leased to their customers.


Due to technical and implementation constraints on the Internet routing 
system and the possibility of routing overload, certain policies may need 
to be enforced by the major transit providers providers in order to reduce 
the number of globally advertised routes.

These potential policies may include setting of limits on the size
of prefixes added to the routing tables, filtering of non-aggregated
routes, etc.  Therefore, addresses obtained directly from the InterNIC
(non-provider-based, also known as portable) are not guaranteed to
be routable on the Internet.

Therefore, if rich connectivity across the Internet is to be maintained, 
follow these steps when requesting address space:

1. Ask your provider

2. Ask your provider's provider

3. Ask the InterNIC registry as a last resort.

Again note that if addresses are allocated directly from the InterNIC, they
will be the least likely to be routable across the Internet.

ISPs requesting address space from the InterNIC are required to complete
the IP template reserved for ISPs.  The template can be found at
rs.internic.net, ftp/templates/ISP-CIDR-block.txt.
[URL = ftp://rs.internic.net/ftp/templates/ISP-CIDR-block.txt]

Any request judged to be lacking sufficient details will be returned to
the requestor for additional information.

In an effort to ensure that CIDR is implemented and utilized as
efficiently as possible, the InterNIC Registry issues blocks of
addresses on appropriate "CIDR-supported" bit boundaries.
Network Providers will also need to be aware of the procedures that define
bit boundary IP address allocation, and utilize these procedures when
assigning IP address space to their respective customers.
The following documents contain important information related to CIDR:

        RFC 1338 - Supernetting: an Address Assignment and Aggregation

        RFC 1482 - Aggregation Support in the NSFNET Policy-Based Routing

        RFC 1517 - Applicability Statement for the Implementation of
                   Classless Inter-Domain Routing

        RFC 1518 - An Architecture for IP Address Allocation with CIDR

        RFC 1519 - Classless Inter-Domain Routing (CIDR) : an Address
                   Assignment and Aggregation Strategy

        RFC 1520 - Exchanging Routing Information Across Provider Boundaries
                   in the CIDR Environment

Determination of CIDR block allocation size is the responsibility of
the InterNIC, this allocation is based on the ISP's 3 - 6 month requirement
and other information the InterNIC deems necessary.  Please note,
allocations are not based solely on a predicted customer base.

Initial allocations will be relatively small.  Subsequent allocated blocks
may be increased based on utilization verification supplied to the

Subsequent allocations of CIDR block addresses will be based on need;
this need will be demonstrated based on the number of reassignment actions
that have been transmitted to the InterNIC Registry.  Reassignment
information is to be forwarded to the InterNIC within 7 days of the
assignment so that the WHOIS may be maintained efficiently.
Transmission of reassignment information is also necessary for the
following reasons:

a) To ensure that a provider has exhausted, or is about to exhaust its
     current CIDR allocation such that an additional allocation is
b) To allow operational people to see which organization is using the
     network and who to contact in the event of operational/security problems,
c) To assist in IP allocation studies.

There are two options available for tracking reassignment information:

  1) Shared WHOIS Project (SWIP)

     Reassignment actions can be submitted by utilizing the database
     exchange format defined by the SWIP project.  Information regarding
     SWIP may be obtained via anonymous FTP from rs.internic.net
     (  The files may be found under the ftp/pub/swip directory.
     [ URL = ftp://rs.internic.net/ftp/pub/swip ]

  2) RWhois

     RWhois is a distributed database for hierarchical information.
     Information on RWHOIS can be found at rs.internic.net, ftp/pub/rwhois.
     [ URL = ftp://rs.internic.net/ftp/pub/rwhois ]

ALL ISPs, regardless of where they receive their CIDR blocks should
either SWIP the reassignment information or establish an RWHOIS server.
If SWIP is the chosen method, ISPs should register with the InterNIC
as an ISP to receive a maintainer ID necessary to SWIP the reassignment

ISPs are required to assign address space based on utilization
efficiency. To this end, ISPs should have documented justification
available for each assignment.  The InterNIC may at any time ask to
see this justification, if not available, this could impact future allocations.

Any ISP whose customer has a requirement of 64 Class C's or more
should forward the template to the InterNIC for review.  The following
information should accompany the request:

    Network engineering plans, including subnets and host counts, and
    hosts per subnet with projected utilization rates and associated
    confidence levels of those projects for one and two years in the

    Deployment schedule for the network, including major milestones
    for each subnet

    Network topology diagrams

All ISPs receiving /16 prefix blocks from the InterNIC will be responsible
for maintaining all IN-ADDR.ARPA domain records for their respective
customers.  The InterNIC Registry will only be responsible for the
maintenance of IN-ADDR.ARPA domain records for those CIDR blocks with
prefixes longer than /16 issued directly from the InterNIC.


Mark Kosters              markk at internic.net        +1 703 742 4795
Software Engineer   InterNIC Registration Services

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