Autonomous System Number List

An autonomous system (AS) is a collection of connected Internet Protocol (IP) routing prefixes under the control of one or more network operators on behalf of a single administrative entity or domain, that presents a common and clearly defined routing policy to the Internet. Each AS is assigned a unique autonomous system number (ASN), for use in Border Gateway Protocol (BGP) routing.

AS numbers are assigned to Local Internet Registries (LIRs) and end user organizations by their respective Regional Internet Registries (RIRs), which in turn receive blocks of ASNs for reassignment from the Internet Assigned Numbers Authority (IANA). The IANA also maintains a registry of ASNs which are reserved for private use (and should therefore not be announced to the global Internet). The allocated AS numbers are defined as 16-bit and 32-bit integers. The length range of 16-bit is between 0 and 65535, and the length range of 32-bit is between 0 and 4294967294. At present, the 16-bit integers which allowed for a maximum of 65,536 assignments is mostly used.

AS Number AS Organization Country Code
AS167 WESLEYAN-AS US (United States)
AS170 DNIC-AS-00170 US (United States)
AS173 Electrical Communications Laboratories JP (Japan)
AS174 COGENT-174 US (United States)
AS186 CUA-AS US (United States)
AS187 DNSCAST-AS US (United States)
AS188 SAIC-AS US (United States)
AS190 DNIC-AS-00190 US (United States)
AS194 NCAR-AS US (United States)
AS195 SDSC-AS US (United States)
AS196 BOEING196 US (United States)
AS205 MONTCLAIR-AS US (United States)
AS206 CSC-IGN-AMER-AS206 US (United States)
AS210 WEST-NET-WEST US (United States)
AS213 DNIC-AS-00213 US (United States)
AS217 UMN-SYSTEM US (United States)
AS220 OOALC-HOSTNET-AS US (United States)
AS223 AS223 US (United States)
AS224 UNINETT AS NO (Norway)
AS225 VIRGINIA-AS US (United States)
AS226 LOS-NETTOS-AS US (United States)
AS228 DNIC-AS-00228 US (United States)
AS229 MERIT-AS-6 US (United States)
AS231 MISU-231 US (United States)
AS237 MERIT-AS-14 US (United States)
AS243 HARRIS-ATD-AS US (United States)
AS250 Foundation EU
AS252 DNIC-AS-00252 US (United States)
AS257 DNIC-AS-00257 US (United States)
AS258 BRAGGSRI-EGP-AS US (United States)
AS260 XCONNECT24 US (United States)
AS262 VERIO US (United States)
AS264 SRINET-AS US (United States)
AS267 NETHER-NET US (United States)
AS268 USUHSNET-AS US (United States)
AS270 AS270 US (United States)
AS271 BCNET-AS CA (Canada)
AS272 CTNOSC-ASN-272 US (United States)
AS273 DNIC-AS-00273 US (United States)
AS275 NTTA-275 US (United States)
AS276 OTS-AS-276 US (United States)
AS278 Universidad Nacional Autonoma de Mexico MX (Mexico)
AS283 MPOWERLABS US (United States)
AS288 European Space Agency (ESA) DE (Germany)
AS289 DNIC-AS-00289 US (United States)
AS291 ESNET-EAST US (United States)