BGP Prefix Lookup
Enter a prefix (or a single address). Answered from our daily copy of the global routing table.
66.231.0.0/19
Announced exactly
- 66.231.0.0/19AS13576SDN CommunicationsRPKI Valid66.231.0.0
- Registry
- ARIN · United States · Feb 11, 2002
- Delegated block
- 66.231.0.0 – 66.231.31.255
Covering routes
No less-specific route covers it.
More-specific routes
- 66.231.0.0/24AS13576SDN CommunicationsRPKI Valid66.231.0.0
- 66.231.2.0/23AS401415Alliance CommunicationsRPKI Valid66.231.2.0
- 66.231.9.0/24AS17203Beresford Municipal Telephone CompanyRPKI Valid66.231.9.0
- 66.231.11.0/24AS17203Beresford Municipal Telephone CompanyRPKI Valid66.231.11.0
- 66.231.12.0/24AS17203Beresford Municipal Telephone CompanyRPKI Valid66.231.12.0
- 66.231.13.0/24AS18785Santel Communications Cooperative, Inc.RPKI Valid66.231.13.0
- 66.231.15.0/24AS13576SDN CommunicationsRPKI Valid66.231.15.0
- 66.231.16.0/24AS399439Mitchell TelecomRPKI Valid66.231.16.0
- 66.231.17.0/24AS399439Mitchell TelecomRPKI Valid66.231.17.0
- 66.231.19.0/24AS6312TrioTel Communications, Inc.RPKI Valid66.231.19.0
- 66.231.21.0/24AS13576SDN CommunicationsRPKI Valid66.231.21.0
- 66.231.22.0/24AS18785Santel Communications Cooperative, Inc.RPKI Valid66.231.22.0
- 66.231.24.0/24AS6312TrioTel Communications, Inc.RPKI Valid66.231.24.0
- 66.231.26.0/24AS13576SDN CommunicationsRPKI Valid66.231.26.0
- 66.231.29.0/24AS13576SDN CommunicationsRPKI Valid66.231.29.0
- 66.231.30.0/23AS63172Venture Communications CooperativeRPKI Valid66.231.30.0
- 66.231.30.0/24AS63172Venture Communications CooperativeRPKI Valid66.231.30.0
- 66.231.31.0/24AS63172Venture Communications CooperativeRPKI Valid66.231.31.0
On the internet, routes are announced as prefixes: an autonomous system tells its neighbours via BGP that it can deliver traffic for, say, 193.166.0.0/15. This tool looks a prefix up in our daily copy of the global routing table and shows three things:
- Exact announcements: which AS originates exactly this prefix. More than one origin (a MOAS) is normal for anycast services and some multihomed networks, and suspicious otherwise.
- Covering routes: less-specific announcements that contain it. Traffic follows the most specific route, so a covering route matters if the more-specific one disappears.
- More-specifics: announcements inside it, which may belong to other networks (customers, or a hijack).
Each announced route is also checked against the RPKI: whether a ROA authorises its origin AS.
The table is the view from APNIC’s route collector. Most of the global table is the same from everywhere, but a route that is filtered before it reaches that collector will not appear.
Frequently asked questions
Why is my /24 not listed but a /16 is?
Your addresses are announced as part of the larger block, and no one announces the /24 separately. That is the normal case for most customers of a provider.
What is a more-specific hijack?
Someone announces a longer prefix inside your space. Because routers prefer the most specific route, traffic goes to them. RPKI with a strict max length makes such announcements invalid.
Can I enter a single address?
Yes. The tool then shows the most specific announced route that contains it.