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AS513 · European Organization for Nuclear Research

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

Examples AS15169 AS13335 AS36459
Autonomous System Non-Profit Announcing
AS513
— European Organization for Nuclear Research
Registry
🇨🇭
IPv4 prefixes
19
IPv6 prefixes
20
IPv4 addresses
354,816
This AS Peer Upstream
Registration
Handle
Organization European Organization for Nuclear Research
Country 🇨🇭 Switzerland (CH)
RIR
Registered
Abuse
Routing summary
19
IPv4 prefixes
20
IPv6 prefixes
354,816
IPv4 addresses
53
Observed peers
home.cern
Announced prefixes
19 v4 · 8 v6 shown
Prefix (CIDR) Version Addresses Description
128.141.0.0/16 IPv4 65,536
128.142.0.0/16 IPv4 65,536
137.138.0.0/16 IPv4 65,536
185.249.56.0/22 IPv4 1,024
188.184.0.0/15 IPv4 131,072
192.16.155.0/24 IPv4 256
192.16.156.0/22 IPv4 1,024
192.16.160.0/22 IPv4 1,024
192.16.164.0/23 IPv4 512
192.16.166.0/24 IPv4 256
192.65.183.0/24 IPv4 256
192.65.184.0/21 IPv4 2,048
192.65.192.0/22 IPv4 1,024
192.65.196.0/23 IPv4 512
192.91.236.0/22 IPv4 1,024
192.91.240.0/22 IPv4 1,024
192.91.244.0/23 IPv4 512
192.91.246.0/24 IPv4 256
194.12.128.0/18 IPv4 16,384
2001:0:808d::/48 IPv6
2001:0:808e::/48 IPv6
2001:0:898a::/48 IPv6
2001:0:bcb8::/47 IPv6
Raw response
{
  "asn": "AS513",
  "handle": "",
  "org": "European Organization for Nuclear Research",
  "country": "CH",
  "rir": "",
  "registered": "",
  "ipv4_prefixes": 19,
  "ipv6_prefixes": 20,
  "addresses_v4": 354816,
  "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 AS513 shows how European Organization for Nuclear Research 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.