BGP Prefix Lookup
Enter a prefix (or a single address). Answered from our daily copy of the global routing table.
2001:428::/32
Announced exactly
- 2001:428::/32AS209CenturyLink Communications, LLCRPKI Not found2001:428::
- Registry
- ARIN · United States · Jul 12, 2000
- Delegated block
- 2001:428:: – 2001:428:ffff:ffff:ffff:ffff:ffff:ffff
Covering routes
No less-specific route covers it.
More-specific routes
- 2001:428:b20::/48AS7359CenturyLink Communications, LLCRPKI Not found2001:428:b20::
- 2001:428:b21::/48AS4015CenturyLink Communications, LLCRPKI Not found2001:428:b21::
- 2001:428:b26::/48AS10753Level 3 Parent, LLCRPKI Not found2001:428:b26::
- 2001:428:3816::/48AS3356Level 3 Parent, LLCRPKI Not found2001:428:3816::
- 2001:428:5805::/48AS3356Level 3 Parent, LLCRPKI Not found2001:428:5805::
- 2001:428:6400::/48AS3356Level 3 Parent, LLCRPKI Not found2001:428:6400::
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.