Textual Representation of Autonomous System (AS) Numbers
Extracted elements (7)
A single textual notation (asplain) is proposed to avoid confusion across documentation, configuration systems, reports, and external tools. The decimal value representation requires no field delimiter, reflecting the lack of internal structure required by AS numbers in inter-domain routing.
All documents, systems, and user interfaces referring to AS numbers MUST use the decimal value (asplain) textual representation.
IANA Registries should use decimal representation (asplain) for AS numbers.
asdot+ notation represents all AS numbers as two decimal integers joined by a period, where the left value is the high-order 16 bits and the right is the low-order 16 bits. For example, AS 65526 is '0.65526' and AS 65546 is '1.10'.
asdot notation uses asplain for AS numbers below 65536 and asdot+ for values 65536 and above. For example, AS 65526 is '65526' and AS 65546 is '1.10'.
asplain notation represents all AS numbers as plain decimal integers without any delimiter. For example, AS 65526 is written '65526' and AS 65546 is written '65546'.
This document does not address matters associated with the security of routing systems.