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AS10310 · Yahoo Holdings Inc.

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

Examples AS15169 AS13335 AS36459
Autonomous System Content Announcing
AS10310
— Yahoo Holdings Inc.
Registry
🇭🇰
IPv4 prefixes
81
IPv6 prefixes
390
IPv4 addresses
78,592
This AS Peer Upstream
Registration
Handle
Organization Yahoo Holdings Inc.
Country 🇭🇰 Hong Kong SAR China (HK)
RIR
Registered
Abuse
Routing summary
81
IPv4 prefixes
390
IPv6 prefixes
78,592
IPv4 addresses
1,028
Observed peers
www.yahooinc.com
Announced prefixes
20 v4 · 8 v6 shown
Prefix (CIDR) Version Addresses Description
27.123.33.0/24 IPv4 256
27.123.34.0/23 IPv4 512
27.123.37.0/24 IPv4 256
27.123.44.0/22 IPv4 1,024
27.123.192.0/23 IPv4 512
27.123.196.0/23 IPv4 512
66.196.64.0/21 IPv4 2,048
66.196.90.0/23 IPv4 512
67.195.249.0/24 IPv4 256
68.142.248.0/24 IPv4 256
68.142.253.0/24 IPv4 256
68.180.128.0/24 IPv4 256
68.180.132.0/23 IPv4 512
68.180.136.0/21 IPv4 2,048
69.147.67.0/24 IPv4 256
72.30.220.0/22 IPv4 1,024
74.6.224.0/22 IPv4 1,024
77.238.168.0/22 IPv4 1,024
77.238.172.0/23 IPv4 512
77.238.174.0/24 IPv4 256
Raw response
{
  "asn": "AS10310",
  "handle": "",
  "org": "Yahoo Holdings Inc.",
  "country": "HK",
  "rir": "",
  "registered": "",
  "ipv4_prefixes": 81,
  "ipv6_prefixes": 390,
  "addresses_v4": 78592,
  "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 AS10310 shows how Yahoo Holdings 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.