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AS2518 · BIGLOBE Inc.

Autonomous system number lookup for network owner details, BGP ASN context, IP prefixes, registration and peer relationships.

Examples AS15169 AS13335 AS36459
Autonomous System NSP Announcing
AS2518
— BIGLOBE Inc.
Registry
🇯🇵
IPv4 prefixes
29
IPv6 prefixes
98
IPv4 addresses
3,670,016
This AS Peer Upstream
Registration
Handle
Organization BIGLOBE Inc.
Country 🇯🇵 Japan (JP)
RIR
Registered
Abuse
Routing summary
29
IPv4 prefixes
98
IPv6 prefixes
3,670,016
IPv4 addresses
214
Observed peers
www.biglobe.co.jp
Announced prefixes
20 v4 · 8 v6 shown
Prefix (CIDR) Version Addresses Description
27.127.0.0/17 IPv4 32,768
49.129.0.0/16 IPv4 65,536
60.236.0.0/14 IPv4 262,144
61.193.0.0/17 IPv4 32,768
61.203.0.0/17 IPv4 32,768
110.233.0.0/16 IPv4 65,536
111.168.0.0/15 IPv4 131,072
118.108.0.0/14 IPv4 262,144
119.238.0.0/15 IPv4 131,072
119.240.0.0/14 IPv4 262,144
119.244.0.0/16 IPv4 65,536
122.130.0.0/15 IPv4 131,072
122.132.0.0/14 IPv4 262,144
125.192.0.0/13 IPv4 524,288
133.200.0.0/13 IPv4 524,288
133.208.0.0/15 IPv4 131,072
202.225.0.0/16 IPv4 65,536
202.247.0.0/17 IPv4 32,768
203.136.0.0/16 IPv4 65,536
210.147.0.0/16 IPv4 65,536
2001:0:1b7f::/49 IPv6
2001:0:3181::/48 IPv6
2001:0:3cec::/46 IPv6
2001:0:3dc1::/49 IPv6
2001:0:3dcb::/49 IPv6
2001:0:6ee9::/48 IPv6
2001:0:6fa8::/47 IPv6
2001:0:766c::/46 IPv6
Raw response
{
  "asn": "AS2518",
  "handle": "",
  "org": "BIGLOBE Inc.",
  "country": "JP",
  "rir": "",
  "registered": "",
  "ipv4_prefixes": 29,
  "ipv6_prefixes": 98,
  "addresses_v4": 3670016,
  "abuse": ""
}
Guide

How to read an ASN profile

An autonomous system is the unit networks use to route traffic between each other. A BGP ASN lookup for AS2518 shows how BIGLOBE Inc. is registered, which IP prefixes are associated with the network, and which peers or upstreams appear in the available routing data.

The announced prefixes table helps you find IP prefixes by ASN and inspect CIDR blocks tied to the organization. The peering section shows neighboring networks it exchanges traffic with — upstreams sell it transit, while peers swap traffic directly. Together they describe both what this network reaches and how it connects.

Use ASN profiles for network owner lookup, incident triage, IP range review and provider research. Treat the data as routing context, not live outage monitoring; BGP changes can move faster than public lookup datasets.

FAQ

Frequently asked questions

What is an Autonomous System Number (ASN)?

An Autonomous System Number, or ASN, is a globally unique identifier for a network operator that controls one or more IP prefixes and exchanges routing information with other networks using BGP. Examples include AS15169 for Google and AS13335 for Cloudflare.

What does an ASN lookup show?

An ASN lookup shows the network owner, organization, RIR, registration details, country, abuse contact, IPv4 and IPv6 prefix counts, sample announced prefixes, and observed peer or upstream relationships when available.

How do I find IP prefixes by ASN?

Enter an ASN such as AS15169 or 15169. The prefix table lists sample IPv4 and IPv6 CIDR blocks associated with that autonomous system, plus counts that help estimate the network size.

What is the difference between a peer and an upstream?

An upstream, also called a transit provider, carries traffic to the wider internet. A peer exchanges traffic directly, often at an internet exchange. Both relationships help explain how an AS connects to other networks.

Is this real-time BGP monitoring?

No. This ASN lookup summarizes routing and registration datasets available to the tool. It is useful for network owner lookup, prefix discovery, and routing context, but not a replacement for real-time BGP monitoring or outage detection.