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                       JPNIC Translated Document

Source document: JPNIC REPORT 8
Date of the source: April 1994
Date of the last update of this translation: November 25, 1995

This is a translation of a JPNIC document. JPNIC provides this
translation for convenience of those who can not read Japanese. But it
may contain mis-translations, and is by no means official. One should
consult the source document written in Japanese for detail.
                IP address allocation by providers

 Recently, the number of organizations connected to the Internet has
exponentially increased worldwide. Due to that, the number of IP address
that are to be allocated has also increased rapidly, and in near future the
following problems have to be faced.

1. Run out of class B address space
2. Due to a rapid rise of the number entries in the router's routing table,
   there will be a shortage of hardware resources (memory of router etc.),
   and human resources for administrating the routing.
3. Exhaustion of the present 32 bit address space.

 The problem stated in 1 and 2 is likely to appear within a short period of
time. For that IESG (Internet Engineering Steering Group) has agreed to
adopt the CIDR (Caseless Inter-Domain Routing) [2] system until there is a
basic solution (until the the IPng is decided and the operation of
the same starts) for the problem mentioned in 3. In accordance to that
the Address Space TaskForce of JEPG/IP (Japanese Engineer & Planning Group/IP)
has been trying technical adjustment from all aspects in order to realize
routing for the allocation of IP address under Japan.

 Keeping the idea of CIDR as a basis, JPNIC is allocating IP addresses within
Japan [3,4]. Moreover, IP address allocation by service providers [1] that are
to be explained here will allocate the possible CIDR addresses and facilitate
the realization of hierarchical routing under CIDR [5].

 At first JPNIC will allocate the sequential IP address blocks that
corresponds to CIDR to its each member network. This is to allocate IP address
to the network organizations (including the networks that are already
connected) that are connected to the member network. Based on these, it will
appoint the member network for allocating address to the networks that are
included in the members address block.

        Pilot project

 As a first step to realize this system, JPNIC has started a pilot project.
This project is to investigate the applicability of the allocation system,
the scope of the organizations that are to be appointed and a part of the
allocation system explained above is to be realized.

 The participants of this pilot project are two member networks of JPNIC and
they are IIJ Internet which is operated by Internet Initiative Japan Inc. and
the SPIN project which is operated by AT&T Jens. (As of 4/1994)

 The objective of appointing the above 2 members is just to find out the
drawbacks of the allocation system, and the operation based on CIDR. However,
although the period is small, sparing of the limited IP address space is not
a welcoming idea.

 For that JPNIC has stressed on the following three points for selecting
the partners.

 o outstanding achievements
 o perform allocation within the project period
 o prompt correspondence to all sorts of problems

 The member networks who could not take part in this project would be able
to utilize the facility of allocation based on these system in future.

 The outline of the pilot project (from now on it will be abbreviated as
project), scope of the IP address allocation by the participating members
appointed by JPNIC and the problems that might have to be faced during the real
allocation procedure is explained below.


 The duration of the project is 6 months, and it is from 1/11/93 to 30/4/94.

 The JPNIC steering committee will report the allocation status of the
participating networks, consider and reinvestigate the problems that are
clear through the progress of the project and decide a mechanism for
the future IP address allocation by the end of this project.

 If the JPNIC steering committee finds it necessary, then the system explained
below might change even if it happens during the project. In that case JPNIC
will inform the participating networks immediately.

 The IP addresses allocated during the period will be considered as formal
allocation and they will be valid even after the project is over. However
the participating networks can not allocate IP addresses to the organizations
that are not connected to the participating networks.

 Allocation of address block

 JPNIC will allocate address blocks to the participating networks. The blocks
will have 256 continuous class C addresses (from now on it will be referred as
1 block) so that they can be used for CIDR. JPNIC will allocate one
independent block to each participating member as soon as they join
the project. After that, the allocation to the organizations connected to
the participating networks has to be performed from the address block
allocated to the network.

 The participating members can apply to JPNIC for additional address blocks,
if the remaining address space of the allocated address block gets too small.

 Procedure for address allocation

 In this project, the participating networks charged with two tasks -one is
examinations of IP address application within 2 class C for organizations
that will be connected to the networks, and the other is to allocate IP
addresses within address-blocks that were assigned to the networks.
Allocation to organizations that are not connected to the participating
networks is never accepted.

 The participating networks will screen the applications based on the
prescribed criterion. Although this criterion (technical guide for obtaining
IP address) is documented in [4], it should be noted that the number of
already obtained IP address will also become a subject of the screening.
Allocation can not be performed by judging only the type of the fresh
application and the number of address.

 However, in order to slow down the routing information, following rules are
to be considered for exceptions [1].

 (If the organization which has already obtained IP addresses use the same
within the organization and does not announce the routing information to the
Internet through the provider from whom the addresses were obtained, then
the organization will be allowed to obtain c1 addresses irrespective of the
number of addresses it has already obtained. In case of changing a provider,
these addresses has to be returned and new addresses have to be reobtained
from another provider.
  In case of returning the previously obtained address, the allocation
will be processed in the normal way.)

 That is, instead of waiting for the judgement from JPNIC, the service provider
will sum up the number of previously obtained addresses and the number of
addresses applied for, compare it with the criterion given in [4], and
allocate address within the scope of 2 * class C. Which means that there are
two cases, one is the case where 1 or 2 class C could be allocated to the
organization which has not obtained any address previously and the case where
the organization has already obtained 1 class C address and in that case
another class C address is allocable.

 Therefore, the service provider must refer to the JPNIC database and confirm
the type and the number of address already obtained by the organization. Now,
for the latter case, if the already obtained addresses are not serial which is
necessary for the newly allocable CIDR address, then serial addresses can be
obtained by returning the previously obtained addresses.

 After the screening, if it is decided that C * 2 number of addresses is
allocable and the applicant agrees, then IP addresses can be allotted from
the address block that has been already obtained from JPNIC.

 For all the other cases, JPNIC will screen the application in the conventional
way and if the allocable address includes class C then the number of the same
will be informed.

 Organizations which still do not have an IP address and want to connect to
the Internet, should consult the technical contact of that network irrespective
of the case whether the network is participating in the project or not.

 The technology for the construction of IP network is improving day by day.
Methods for constructing networks by using multiple class C address is
already in practice. It is recommended to seek advice from experts regarding
this matter.                                    (Shin Yoshimura, IIJ)


[1] JPNIC, [Guide related to IP address allocation by member networks of
    JPNIC] October.1993

[2]V.Fuller,et al.,Classless Inter-Domain Routing(CIDR):an Address
   Assignment and Aggregation Strategy,RFC1519,Sept.1993

[3]E.Gerich,Guidelines for Management of IP Address Space,RFC1466,

[4]JEPG/IP,Address Space TaskForce,[Technical guide for obtaining IP
   address] February.1993

[5]Y.Rekhter,et al.,An Architecture for IP Address Allocation with

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