Simplify assignment of first ASN

Summary of proposal:

32-bit AS Numbers are now supported across the Internet.

The needs based assignment policy, published in 1996 and deployed following RFC 1930, can now be rethought. If accepted, this proposed policy would alter the balance slightly in favour of administrative ease. It does this by removing the needs assessment for the first AS Number assigned to an IP prefix holder.

The current needs assessment policy would continue to apply to any additional AS Numbers a prefix holder requests. They would need to demonstrate a new, unique routing policy.

Policy text:

a. Current policy text

2.0 Assignment Criteria

In order to help decrease global routing complexity, a new AS Number should be used only if a new external routing policy is required, see RFC1930.

A network must be multihomed in order to qualify for an AS Number.

When requesting an AS Number, the routing policy of the Autonomous System must be provided. The new unique routing policy should be defined in RPSL language, as used in the RIPE Database.

b. New policy text

2.0 Assignment Criteria

Legitimate holders of an IP address prefix allocated or assigned directly by the RIPE NCC, may be assigned their first AS Number without providing a needs justification. Once the AS number is in use, its routing policy should be registered.

In all other cases, additional AS Numbers may only be assigned when a new external routing policy is required for a multihomed network.

When requesting an additional AS Number, its routing policy must be provided and the requester’s already held AS Numbers must be in use. The new unique routing policy should be defined in RPSL language, as used in the RIPE Database.

Rationale:

The balance between the complexity of inter-domain routing (see RFC 1930) and the complexity of administration slightly favours lower administrative complexity. The ready availability of AS Numbers does not mean that they should be made available to significantly increase the complexity of inter-domain routing.

It is reasonable to reduce the administrative overhead to both requesters and the RIPE NCC for the first AS Number a network requests.

Over the last 20 years, the RIPE NCC has assigned under 25,000 AS Numbers from the 32-bit part of the IANA Autonomous System (AS) Numbers registry. If the future is similar to the past, and all RIRs are assigned AS Numbers at a similar rate, consuming the pool would take over 30,000 years.

a. Arguments supporting the proposal

This policy proposal would not make AS Numbers available to anyone without space which is intended to be independently routed. It won’t add to deaggregation.

Removing the needs assessment reduces the likelihood that people will lie to the RIPE NCC. This is a good thing.

Removing the needs assessment reduces the time required to request and assign resources. This small efficiency gain is a good thing.

Removing the needs assessment from initial ASN assignments is likely to make new BGP based products available to single-homed customers. This would benefit the customers and the providers.

This proposal does not change the policy for an additional AS Number request by a prefix holder. A single entity could only get multiple AS Numbers if they qualify under the existing policy.

b. Arguments opposing the proposal

Making AS Numbers available to single-homed networks would probably mean an increase in AS Numbers in the global routing table. This could speed up the equipment replacement cycle for networks that maintain a view of all other networks.

Note: In order to provide additional information related to the proposal, details of an impact analysis carried out by the RIPE NCC are documented below. The projections presented in this analysis are based on existing data and should be viewed only as an indication of the possible impact that the policy might have if the proposal is accepted and implemented.

A. RIPE NCC's Understanding of the Proposed Policy

It is the RIPE NCC’s understanding that, if this proposal is accepted and implemented, it will be possible to request the first AS Number without providing a need justification if both of the following conditions are met: first, that the requester legitimately holds an IP prefix distributed directly by the RIPE NCC through allocations and PI assignments, including those received via permanent policy transfer or M&A, and excluding ranges received via temporary policy transfer or temporary assignment; and second, that the requester holds either no AS Numbers or only those that are Legacy or were received via temporary transfers or temporary assignment.

Qualifying resources assigned to End Users must comply with the “Contractual Requirements for Provider Independent Resource Holders in the RIPE NCC Service Region”.

RIPE Database documentation of the routing policy will not be required at the moment of the request, but it will be as soon as the AS Number assigned under this rule is in use. The multihoming requirement will not apply to this AS Number.

The policy requirement to provide an internet routing policy for a multihomed network will still apply to the requests for additional AS Numbers and for the first AS Number in the remaining cases.

If the proposal is accepted, a new policy document, “Autonomous System (AS) Number Assignment Policies”, will obsolete the current document ripe-679.

B. Impact of Policy on Registry and Addressing System

Address/Internet Number Resource Consumption:
The RIPE NCC foresees a slightly increased volume of requests for AS Number and IPv6 PI assignments if this proposal is implemented.

Fragmentation/Aggregation:
After analysing the data that is currently available, the RIPE NCC does not anticipate any significant impact in this area if this proposal is implemented.

C. Impact of Policy on RIPE NCC Operations/Services

Software Engineering:
A medium impact is expected due to the software development needed to update the request form for the first AS Number and keep track, starting from the implementation date, of which resource holders already made use of the option to request an AS Number without justification. A low impact is expected on RIPE Database services.

Registration Services:
If this proposal is implemented, RIPE NCC Registration Services expects the evaluation of requests for the first AS Number without justification to be slightly simpler. As we are not expected to proactively monitor policy compliance with the requirement of registering the routing policy in the RIPE Database when these ASes become active, we will inform the requesters about this on approval.

It is possible that members might need clarification about the different documentation requirements if they are requested to provide up-to-date routing policies during audits. registry checks or the evaluation of additional AS Number requests.

RIPE NCC Registration Services will continue the AS Number clean-up activity, as this policy change makes it easier to request a first AS Number. As a result, some requesters may request an AS Number and only realise afterwards that they do not need it.

RIPE NCC Registration Services will follow up on cases that appear to be contrary to the intent of this policy, such as repeatedly requesting and subsequently returning or transferring the first AS Number.

Learning & Development:
If this proposal is implemented, our training and certification services will not be impacted.

D. Legal Impact of Policy

After analysing the data that is currently available, the RIPE NCC does not anticipate any significant impact in this area if this proposal is implemented.

E. Implementation

With the information currently available, it is expected that implementing the proposal would have a medium impact in terms of the software development needed to facilitate the policy changes in the RIPE NCC’s internal systems. Internal and external processes and documentation would also need to be updated and approved internally for publication.