RTSAK FAQ - Frequently Asked Questions

RTSAK (Route Tools Swiss Army Knife) is a free BGP and routing analysis tool. We provide AS lookups, BGP route analysis, and prefix origin validation for network operators and security researchers.

Yes. All routing analysis tools are free with no registration required.

Network operators, NOC teams, security researchers, and anyone investigating internet routing - peering decisions, troubleshooting connectivity, detecting prefix hijacks, or understanding traffic paths.

BGP routing tables update continuously. Our data reflects recent routing state, though propagation delays mean changes take minutes to appear globally.

An AS is a network or group of networks under single administrative control that presents a common routing policy to the internet. Each AS has a unique AS Number (ASN).

Check your IP allocation from your regional internet registry (RIR), or query any IP address you control to see its announcing AS.

Transit is paid connectivity where one AS carries another's traffic to the full internet. Peering is mutual exchange of customer traffic, typically settlement-free between networks.

The AS may exist but not currently announce routes (dormant), or may be used only for internal purposes without public routing.

Yes. Large organizations often operate several ASNs for different business units, geographic regions, or technical purposes (e.g., acquisition of other companies).

Border Gateway Protocol is how networks share reachability information. When your network announces a prefix, that advertisement propagates globally, telling other networks how to reach your addresses.

Adding your ASN multiple times to the path makes that route less preferred. It's used to influence inbound traffic engineering - pushing traffic to other links.

BGP routing is distributed. Each network makes independent decisions based on its own policies, so paths vary by vantage point. This is normal and expected.

Unstable links cause rapid route withdrawals and re-announcements. Persistent flapping may trigger route dampening by other networks, temporarily ignoring the unstable routes.

Most changes propagate globally within minutes. Complex situations involving dampening or filtering may take longer.

When the same prefix is announced by multiple ASNs. This isn't always malicious - legitimate scenarios include anycast, authorized co-hosting, and transitions.

A Route Origin Authorization is a cryptographically signed statement declaring which AS is authorized to originate a prefix. It's the strongest form of origin validation.

If you have direct RIR allocation, you can create ROAs through your RIR's portal (ARIN, RIPE, APNIC, LACNIC, AFRINIC). If you have provider-assigned space, work with your provider.

Networks implementing RPKI filtering may drop invalid routes. Coverage is growing but not universal - not all networks filter yet.

Contact the RIR responsible for the prefix, your upstream providers, and the prefix owner if identifiable. Include evidence from route lookup showing unauthorized origin.

A /24 is 256 IP addresses. Larger prefixes (like /16 = 65,536 IPs) are more aggregated. Many networks filter prefixes smaller than /24 in IPv4 to limit routing table size.

Tags attached to routes that affect how other networks treat them. Used for traffic engineering, blackholing, and policy signaling between networks.

Checking whether the AS announcing a prefix is authorized to do so, using IRR records, RPKI ROAs, or RIR allocation data.

A facility where multiple networks connect to exchange traffic directly rather than through transit providers. IXPs improve latency, reduce costs, and increase redundancy. --- Need to analyze routing? Try our AS Lookup, BGP Routes, or Prefix Origin tools.