BGP Prefix Lookup
Enter a prefix (or a single address). Answered from our daily copy of the global routing table.
2403:a200::/32
Announced exactly
- 2403:a200::/32AS1742821Vianet.Co.,LtdRPKI Valid2403:a200::
- Registry
- APNIC · China · Jul 31, 2010
- Delegated block
- 2403:a200:: – 2403:a200:ffff:ffff:ffff:ffff:ffff:ffff
Covering routes
No less-specific route covers it.
More-specific routes
- 2403:a200:9999::/48AS133111CERNET New Technology Co., LtdRPKI Valid2403:a200:9999::
- 2403:a200:a100::/48AS1742821Vianet.Co.,LtdRPKI Valid2403:a200:a100::
- 2403:a200:a1ff::/48AS4811China Telecom (Group)RPKI Valid2403:a200:a1ff::
- 2403:a200:a20f::/48AS1742821Vianet.Co.,LtdRPKI Valid2403:a200:a20f::
- 2403:a200:a2ff::/48AS23724IDC, China Telecommunications CorporationRPKI Valid2403:a200:a2ff::
- 2403:a200:a3ff::/48AS58466CHINANET Guangdong province networkRPKI Valid2403:a200:a3ff::
On the internet, routes are announced as prefixes: an autonomous system tells its neighbours via BGP that it can deliver traffic for, say, 49.224.0.0/14. 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.