Autonomous System Response Fields

Every Autonomous System (AS) lookup returns the fields below. Each JSON payload always contains every field: when a value cannot be determined, it is set to null. Examples are illustrative values, not one single response.

root

Top level

Who holds the Autonomous System and how it is registered.

allocated date-time
The date and time when the Autonomous System was allocated, in ISO 8601 format.

Example "2009-09-02T00:00:00.000+00:00"

asn integer
The Autonomous System Number (ASN) that uniquely identifies an Autonomous System on the Internet.

Example 2906

country_code string
The ISO 3166-1 alpha-2 code of the country where the resource holder is legally based. This may not correspond to where the IP addresses are used.

Example "US"

domain string
The top-level domain name associated with the organization that holds the Autonomous System.

Example "netflix.com"

name string
The name of the organization that owns the Autonomous System.

Example "Netflix Streaming Services Inc."

registry string
The Regional Internet Registry (RIR) with which the Autonomous System is registered.
One of
  • AFRINIC
  • APNIC
  • ARIN
  • LACNIC
  • RIPE_NCC

Example "ARIN"

type string
Classifies the usage type of the Autonomous System.
One of
  • business
  • education
  • government
  • hosting
  • inactive
  • isp

Example "isp"

updated date-time
The date and time when the Autonomous System record was last updated, in ISO 8601 format.

Example "2024-06-15T00:00:00.000+00:00"

prefixes

Prefixes

The address blocks the Autonomous System announces. Entries in ipv4 and ipv6 have the same fields, documented once under ipv4[].

prefixes.ipv4_count integer
The number of IPv4 addresses announced by the Autonomous System.

Example 223232

prefixes.ipv6_count integer
The number of IPv6 addresses announced by the Autonomous System.

Example 233371040218408015885280215040

prefixes.ipv4 object[]
The IPv4 prefixes announced by the Autonomous System.
prefixes.ipv6 object[]
The IPv6 prefixes announced by the Autonomous System, with the same fields as ipv4 entries.
prefixes.ipv4[].cidr string
The address block in Classless Inter-Domain Routing notation: its starting IP address and prefix length, which give the range and size of the block.

Example "8.8.8.0/24"

The ISO 3166-1 alpha-2 code of the legal location of the address block. This may not correspond to where the IP addresses are used.

Example "US"

A reasonably descriptive name as it appears in WHOIS. It consists of capitals, dashes (-) and digits, and starts with a capital.

Example "GOOGLE"

The Regional Internet Registry (RIR) responsible for allocating and registering the prefix.
One of
  • AFRINIC
  • APNIC
  • ARIN
  • LACNIC
  • RIPE_NCC

Example "ARIN"

The assignment status of the block, indicating its allocation purpose and whether it can be transferred between service providers. The set of values depends on the Regional Internet Registry responsible for the address space.

Example "allocation"

relationships

Relationships

The Autonomous Systems this one exchanges traffic with, as seen in BGP.

relationships.downstreams integer[]
ASNs that primarily receive their Internet traffic from this Autonomous System. Downstream networks are typically smaller networks or customers to which this AS provides Internet access or transit.
relationships.peers integer[]
ASNs that exchange traffic directly with this Autonomous System under a mutual agreement, typically to improve efficiency and reduce reliance on upstream providers, often without payment.
relationships.upstreams integer[]
ASNs from which this Autonomous System primarily receives its Internet traffic. An upstream is typically a larger network or ISP that this AS pays for access or transit to reach the rest of the Internet.