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prop-064-v001: Change to assignment policy for AS numbers
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Authors:   James Spenceley
           james@vocus.com.au

Version:   1

Date:      22 July 2008


1.  Introduction
----------------

The policy seeks to create awareness earlier within the community for
the need to support 4-byte AS numbers without mandating an absolute
final adoption of 4-byte AS numbers.


2.  Summary of current problem
------------------------------

The current policy has three critical dates with associated policy
changes for the assignment of 4-byte AS numbers as documented in
APNIC-094-v003, "Policies for Autonomous System number management in
the Asia Pacific region [1]:

1 January 2007  APNIC assigns two-byte AS numbers by default.
                APNIC assigns four-byte AS numbers on request.


1 January 2009  APNIC assigns four-byte AS numbers by default.
                APNIC assigns two-byte AS numbers on request.


1 January 2010  APNIC ceases to make any distinction between two- and
                four-byte AS numbers.
                APNIC assigns from an undifferentiated four-byte AS
                number pool.


As the policy currently stands today, we have a specific jump from
'must request a 2-byte AS' to 4-byte AS numbers being generally
assigned.

Currently LIRs may if they choose, simply continue to request 2-byte
AS numbers until 1 January 2010 at which time APNIC will begin 
assignment of 4-byte AS numbers from without differentiation,

This places little requirement on the general provider community
to support 4-byte AS numbers or equipment vendors to implement
and support 4-byte AS numbers.


3.  Situation in other RIRs
---------------------------

The other RIRs assign 4-byte ASNs in the same way as APNIC.

If successful, it is expected that this policy will be presented to
the other RIRs for adoption.


4.  Details of the proposal
---------------------------

4.1 This proposal seeks to create an intermediary stage where LIRs will
    be assigned a 4-byte AS number by default unless it is unsuitable.

    An LIR requesting a 2-byte AS number would need to demonstrate
    that one (or more) of their peers or transit providers are
    unable or unwilling to support a 4-byte AS number.


4.2 An LIR can demonstrate the need for a 2-byte AS number by 
    submitting supporting documentation such as an email or trouble
    ticket stating that that the peer or provider is unable or unwilling
    to accept a 4-byte AS number.


4.3 The intermediary stage is proposed between the two existing stages:

    1 January 2009  APNIC assigns four-byte AS numbers by default.
                    APNIC assigns two-byte AS numbers on request.

        and ....

    1 January 2010  APNIC ceases to make any distinction between two-
                    and four-byte AS numbers.
                    APNIC assigns from an undifferentiated four-byte AS
                    number pool.


5.  Advantages and disadvantages of the proposal
------------------------------------------------

5.1 Advantages

  - The greater awareness and the earlier delegation of 4-byte AS
    numbers is expected to create greater demand on Service Providers to
    support 4-byte AS numbers.

  - More 4-byte AS numbers will be seen in routing tables.

  - Makes more service providers aware of their requirement to support
    4-byte AS numbers earlier.

  - The extent of people unwilling to support 4-byte AS numbers will be
    known and documented. This will provide feedback as to the state of
    deployment and readiness to begin general assignments.

  - Provides more pressure to vendors and Service Providers to
    implement 4-byte code.

  - Will encourage Service Providers to request 4-byte code from their
    vendors, and provides more pressure to equipment vendors and
    Service Providers alike.

  - Increase the chance of an orderly transistion when 4-byte AS
    numbers are delegate as part of the general pool.

  - Creates greater awareness of the need to support 4-byte AS numbers
    as more parties become in involved in the application for a 2-byte
    AS number.


5.2 Disadvantages

  - Could create greater administrative overhead on APNIC staff.


6.  Effect on APNIC members
---------------------------

The proposal impacts all APNIC members.


7.  Effect on NIRs
------------------

The proposal has no direct impact on NIRs, but impacts members of NIRs
in the same way it impacts APNIC members.


8.  References
-------------

[1] Policies for Autonomous System number management in the Asia Pacific
    region
    http://www.apnic.net/policy/asn-policy.html