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In-depth guides to how the internet routes - and how it is secured. Written for engineers, with worked examples you can inspect live.
What is BGP? Border Gateway Protocol Explained
BGP (Border Gateway Protocol) is how networks tell each other which IP addresses they can reach. How sessions, AS-paths and best-path selection work.
What is an ASN? Autonomous System Numbers Explained
An ASN (Autonomous System Number) identifies a network on the internet: 16- vs 32-bit ASNs, reserved ranges, how to get one and how to look one up.
RPKI Explained: Securing BGP Route Origins
RPKI lets address holders authorize which network may announce their prefixes, so routers can drop hijacks. How ROAs, validators, ROV and maxLength work.
What Is a ROA? Route Origin Authorization Explained
A ROA is a signed RPKI object stating which AS may originate a prefix. Its fields, maxLength pitfalls, creating ROAs at your RIR and how ROV uses them.
RPKI Validators and Route Origin Validation (ROV)
What an RPKI validator does, how routers use its output for route origin validation, the Valid, Invalid and NotFound states, and how to deploy ROV safely.
ASPA Explained: Validating the BGP AS-Path
ASPA (Autonomous System Provider Authorization) extends RPKI to validate the BGP AS-path and catch route leaks. How ASPA objects and hop checks work.
ASPA Check: How to Verify a Network's Authorized Providers
How to run an ASPA check: see which providers an ASN has authorized, spot transit-free networks, validate an AS-path hop by hop and fix common mistakes.
BGP Route Leak vs Hijack: Differences, Detection and Prevention
A hijack announces someone else's prefix; a route leak passes on routes that should stay private. How each looks in BGP and how ROV and ASPA catch them.
How to Check if an IP Address Is Malicious
A triage workflow for suspicious IPs: threat score and flags, network context, Tor/VPN/proxy checks, false positives and automating the check via API.
The IPv4 Transfer Market Explained
Why IPv4 addresses are bought and sold, how a registry transfer works, what inter-RIR and M&A transfers are, and how to read the RIR transfer logs.