BGP Prefix Lookup
Enter a prefix (or a single address). Answered from our daily copy of the global routing table.
205.164.64.0/18
Announced exactly
- 205.164.64.0/18AS174Cogent Communications, LLCRPKI Not found205.164.64.0
- Registry
- ARIN · United States · Mar 15, 1995
- Delegated block
- 205.164.64.0 – 205.164.127.255
Covering routes
No less-specific route covers it.
More-specific routes
- 205.164.76.0/24AS174Cogent Communications, LLCRPKI Not found205.164.76.0
- 205.164.96.0/24AS399002Nova Cablevision, Inc.RPKI Not found205.164.96.0
- 205.164.97.0/24AS399002Nova Cablevision, Inc.RPKI Not found205.164.97.0
- 205.164.98.0/24AS399002Nova Cablevision, Inc.RPKI Not found205.164.98.0
- 205.164.99.0/24AS399002Nova Cablevision, Inc.RPKI Not found205.164.99.0
- 205.164.100.0/24AS399002Nova Cablevision, Inc.RPKI Not found205.164.100.0
- 205.164.101.0/24AS399002Nova Cablevision, Inc.RPKI Not found205.164.101.0
- 205.164.102.0/24AS399002Nova Cablevision, Inc.RPKI Not found205.164.102.0
- 205.164.103.0/24AS399002Nova Cablevision, Inc.RPKI Not found205.164.103.0
- 205.164.104.0/22AS272575DELTA R SEGURANCA E SERVICOSRPKI Not found205.164.104.0
- 205.164.108.0/22AS400639Outer Reach Broadband LLCRPKI Valid205.164.108.0
- 205.164.112.0/24AS33176DTC CableRPKI Not found205.164.112.0
- 205.164.113.0/24AS33176DTC CableRPKI Not found205.164.113.0
- 205.164.114.0/24AS395839HOSTKEYRPKI Valid205.164.114.0
- 205.164.115.0/24AS174Cogent Communications, LLCRPKI Not found205.164.115.0
- 205.164.117.0/24AS174Cogent Communications, LLCRPKI Not found205.164.117.0
- 205.164.119.0/24AS174Cogent Communications, LLCRPKI Not found205.164.119.0
- 205.164.120.0/24AS134143Kinetix NetworksRPKI Not found205.164.120.0
- 205.164.121.0/24AS134143Kinetix NetworksRPKI Not found205.164.121.0
- 205.164.122.0/24AS134143Kinetix NetworksRPKI Not found205.164.122.0
- 205.164.123.0/24AS134143Kinetix NetworksRPKI Not found205.164.123.0
- 205.164.124.0/24AS134143Kinetix NetworksRPKI Not found205.164.124.0
- 205.164.125.0/24AS134143Kinetix NetworksRPKI Not found205.164.125.0
- 205.164.126.0/24AS134143Kinetix NetworksRPKI Not found205.164.126.0
- 205.164.127.0/24AS134143Kinetix NetworksRPKI Not found205.164.127.0
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.