Change to AS number policy

The final phase of the four-byte AS number policy begins 1 January 201

From 1 January 2010, APNIC will cease to make a distinction between four-byte only and two-byte only Autonomous System (AS) numbers.

Instead, all AS numbers will be considered to be four-byte AS numbers. So, when an AS number request is made, only four-byte AS numbers will be allocated.

This change marks the third phase of the transition to four-byte AS numbers. For more information on the implementation phases of the four-byte AS number policy, please see "Policies for Autonomous System number management in the Asia Pacific region" section 6.3, "Timetable for moving from two-byte only AS numbers to four-byte AS numbers"

To learn more about how the transition to four-byte AS numbers may affect your network, see the AS number section of the ICONS website.

If you have any questions or need further assistance, please contact the APNIC Helpdesk.