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This document is obsoleted by ripe-72, version 0.7 of this document

This document describes the procedures for the reassignment of IP
network numbers from blocks obtained from the RIPE Network Coordination

Centre. It deals with items as providing information for the RIPE and

US NIC databases, as well as reassignment of IP addresses in light of

the "Supernetting" proposal, as documented in RFC 1338, by Vince Fuller

et al.


Since May 1st 1992, the RIPE Network Coordination Centre (NCC) is

acting as a delegated registry for IP networks numbers to NICs and NOCs

in Europe. It is RIPE NCC policy not to give out network numbers to

individual organisations, who should refer in turn, to their IP network

service provider.

The mission of the RIPE NCC is to give network numbers to the various

service providers and NICs. The NICs and NOCs can then reassign the

actual IP network numbers to organisations requesting IP network


Class B Network Number Allocation Procedure

Service providers can request Class B network numbers on a one-by-one

basis from the RIPE NCC. Because class B address space is a critical

resource, a request for a class B network number must be accompanied by

a justification in terms of the requesting organisation's size, current

network and expected network growth. The requestor should also make

clear why they cannot use a block of class C network numbers to achieve

their goals. The
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This document provides guidelines to Local Internet Registries (LIRs) on the steps to take when the organisation operating an LIR changes ownership (due to a merger, sale or takeover) or stops serving entirely as an LIR.


Table of Contents

1.0 Introduction Link: #1.0

2.0 LIR Ownership Change Link: #2.0

2.1 IP Address Space Link: #2.1

2.2 Service Agreement Link: #2.2

2.3 Change in Operating Organisation Link: #2.3

2.4 Contact Person(s) Link: #2.4

2.5 RegID Link: #2.5

2.6 Transfers of Address Allocations Link: #2.6

2.7 Takeover fee Link: #2.7

3.0 Closing an LIR Link: #3.0

This section is replaced by the RIPE NCC organisational document "Closure of LIR and Deregistration of Internet Number Resources Link: closure ".

4.0 When an LIR is Closed by the RIPE NCC Link: #4.0

This section is replaced by the RIPE NCC organisational document "Closure of LIR and Deregistration of Internet Number Resources Link: closure ".

1.0 Introduction

When an organisation or company operating an LIR changes ownership status or stops serving as an LIR there are financial, IP address space and RIPE Database issues that need resolving. Therefore, the RIPE NCC must always be contacted when an LIR changes ownership or closes.

2.0 LIR Ownership Change

In the case of an LIR ownership change, the LIR should contact the RIPE NCC at [email protected] Link: mailto:[email protected] .

Only registered LIR contact person(s) can discuss the change of an LIR ownership with the RIPE NCC.

The following steps are required to change the organisation operating an LIR:

1. Clarify the type of change:

  • A takeover of one LIR by another LIR, closing one of the LIRs.

  • A takeover of one LIR by another LIR, both remain open.

  • A takeover of an LIR by a non-LIR.

2. Outline the details of the change, stating:

  • The reason for the change of organisation.

  • The name of the company/companies involved.

  • The number of LIRs affected by the change.

  • The RegID(s) of the LIR(s) affected by the change.

3. Present the following documents to the RIPE NCC:

  • Confirmation from all parties agreeing to the change (See section 2.3).

  • Updated list of contact person(s) (See section 2.4).

  • Updated billing e-mail contact details, including any changes to VAT number.

  • A new service agreement, if applicable (See section 2.2).

  • Legal documentation supporting the name change, if applicable (See section 2.2).

  • Overview of utilisation in all allocations (See section 2.6).

2.1 IP Address Space

Following any type of change (such as mergers, acquisitions or takeovers) of an organisation operating an LIR, the
RIPE NCC will review requests using the same standards
as any other Internet Registry, particularly the US NIC.

Class C Allocation Procedures

NICs and NOCs accepting a block of class C numbers agree to adhere to
the following procedures:

A) The RIPE NCC will assign complete class C blocks to individual NICs
and NOCs. They can be requested from <[email protected]>.

B) In order to prevent implementation problems, network numbers ending
with 0 or 255 should NOT be reassigned.

C) Full information about reassigned network numbers must be reported
back to the RIPE NCC and the US NIC in full RIPE database format (ref
ripe-13). The complete entries should be sent immediately after
reassignment to <[email protected]> and <[email protected]>
Unfortunately, the RIPE NCC is not yet ready to accept block entries for
the RIPE database, so you must send in each individual entry.

D) Reassignment of class C network numbers should be done in a manner
that facilitates Supernetting (see next section).

E) Requests for network numbers should be reasonable. All NICs and NOCs
should prevent stockpiling of network numbers.

F) On first request from the RIPE NCC, the class C network numbers not
yet reassigned, must be returned to the RIPE NCC.


NICs and NOCs reassigning IP network numbers are urgently requested to
read the Supernetting proposal by Vince Fuller et al. This document can
be obtained from the rfc section of the RIPE document store or other RFC
servers. It is called rfc1338.txt.
The Supernetting proposal was made to reduce the increase of routing
table size in the current Internet. It proposes to create a hierarchy
of IP network numbers, which can then be aggregated resulting in less
routing table entries in routing equipment. While this proposal has not
been formally adopted we expect that something at least along the same
principle will be implemented in the near future.

Here is how it works:

If an organisation A needs 8 class C network numbers, the numbers should
be given out in such a way that the routing information for each of
these 8 networks could appear as one entry with the correct mask in

More concretely:

Service provider S hands out networks 192.24.8 through 192.24.15 to
organisation A. These networks can then appear in routing equipment as a
supernet route to 192.24.8 with mask This way 8 class C
network numbers appear as one routing table entry.

The guidelines that can be derived from the Supernetting proposal are:

A) Service providers should reserve blocks of class C network numbers from
their allocation for each organisations requesting class C network numbers.

B) The size of these blocks should always be a power of 2.

C) The numbers in these blocks should be contiguous.

D) The blocks should start on bit boundaries.
(ie powers of 2, AND multiples of the block size)

E) The blocks reserved for an organisation should be sufficient for a
reasonable expected growth over the next few years.

F) Multi-homed organizations may obtain address space from one of their
providers, the RIPE NCC, or the global NIC, as is appropriate to their
network configuration. These organisations are strongly encouraged to
the status of any IP address allocations that are held by the new organisation.

2.2 Service Agreement

When an organisation operating an LIR changes ownership, a new service agreement may need to be signed. The RIPE NCC will need to request a new service agreement from the new owners if:

  • The organisation operating the LIR changes name, or

  • The LIR wishes to change their RegID.

The registration documentation from the relevant Chamber of Commerce, or its country equivalent, supporting the name change must be submitted to the RIPE NCC.

The Standard RIPE NCC Service Agreement is available from the RIPE Document Store at: Link:

If the organisation operating the LIR does not change its name and keeps the original RegID, the LIR can continue operating under the same service agreement.

2.3 Change in Operating Organisation

In cases where an organisation operating an LIR takes over one or more LIRs, confirmation of the takeover from all parties involved or their legal successors must be included.

2.4 Contact Person(s)

It is very important to notify the RIPE NCC, if there is a change of contact person(s). This is essential, as only registered contact person(s) can submit Internet resource requests to the RIPE NCC and provide updates to our internal registry files.

If the contact person(s) of the affected LIR has changed, the RIPE NCC may adjust the Assignment Window of the LIR until the contact person(s) is up-to-date with RIPE NCC procedures and RIPE community policies.

If there are no current registered contacts remaining with the LIR, a fax signed by the Managing Director of the LIR on organisation letterhead is required to implement these

changes. These changes should include the new registered contact person(s) for the LIR.

2.5 RegID

It is not necessary to obtain a new Registry Identifier (RegID) if the name of the organisation that operates the LIR changes. The RegID is merely an internal identifier used by the RIPE NCC to distinguish the various LIRs. It does not have to correspond to the legal name of the organisation operating the LIR.

If an LIR insists on changing their RegID, a fee corresponding to the sign-up fee for a new LIR will be charged to cover additional administrative work generated. Please see the current version of the RIPE NCC Charging Scheme available from the RIPE Document Store at: Link:

2.6 Transfers of Address Allocations

All transfers of address allocations from one LIR to another LIR (or to a non-LIR) require approval by the RIPE NCC. It is expected that all database objects relating to this allocation be correct and up-to-date before the transfer occurs. Transferred allocations containing a large amount of unassigned address space may be set aside and kept by the RIPE NCC for guidance.

If you have any questions concerning this, please do not hesitate to
call or mail us at [email protected].
until the other allocations held by the LIR are considered fully used (about 80%). Once the LIR has reached full utilisation in its other allocations, the reserved allocations will be made available to the LIR. For further details on allocation policy, please refer to the document "IPv4 Address Allocation and Assignment Policies in the RIPE NCC Service Region" available from the RIPE Document Store at: Link:

2.7 Takeover Fee

In cases where an organisation operating an LIR takes over one or more LIRs, a takeover fee is due for every LIR taken over (e.g. if three LIRs are taken over, the fee is paid three times). All current outstanding invoices for the LIRs being taken over will also have to be paid in full.

The transfer of address allocations also incurs a takeover fee and does not vary according to the amount of address space being transferred (e.g. if three allocations are being transferred from LIR A to LIR B, the fee is only paid once).

3.0 Closing an LIR

This section is replaced by the RIPE NCC organisational document "Closure of LIR and Deregistration of Internet Number Resources" available from the RIPE Document Store at: Link: .

4.0 When an LIR is Closed by the RIPE NCC

This section is replaced by the RIPE NCC organisational document "Closure of LIR and Deregistration of Internet Number Resources"available from the RIPE Document Store at: Link: .