In a situation similar to the exhaustion of IPv4 address space, the current pool of unassigned 2-byte Autonomous System (AS) numbers is predicted to run out.
While IPv6 is the industry's preferred solution to the IPv4 shortage, a new expanded system, which extends AS numbers to four bytes in length, is designed to address the AS number shortage.
Working cooperatively through the NRO (the Number Resource Organization) and in conjunction with ICANN (Internet Corporation for Assigned Names and Numbers) the world's five Regional Internet Registries (RIRs) are taking a coordinated approach to the transition from 2-byte to 4-byte AS numbers.
Network builders may experience connectivity issues if their own equipment or the routing policies and hardware of their upstream providers is not compliant with this emerging standard.
To assist the Internet community to address these issues, share information about solutions and on-going issues, and to provide a forum for general discussion about the introduction of 4-byte Autonomous System numbers, ICONS is providing this information in the hope that other community members, including ISPs, users, and vendors can contribute up-to-date information for the benefit of all community members.
RIR Warns To Upgrade Routers
Regional Internet Registries (RIRs) have warned that routers and network
management software should be upgraded ahead of the increased
distribution of 4-byte AS numbers. Press Release