BGP & Internet Routing
How the internet routes traffic between networks. BGP fundamentals, ASNs, peering, transit, route filtering, and RPKI security.
What Is BGP?
How BGP routes traffic between autonomous systems to make the internet work.
6 min readASN Numbers Explained
How Autonomous System Numbers are allocated and used in internet routing.
4 min readInternet Peering & Transit
How ISPs and networks exchange traffic through peering agreements and transit providers.
5 min readBGP Route Filtering & Prefix Lists
Learn how BGP route filtering prevents route leaks and hijacks using prefix lists, AS-path filters, and IRR-based filtering.
11 min readRPKI: Securing BGP with Route Origin Validation
How Resource Public Key Infrastructure (RPKI) prevents BGP hijacking by cryptographically validating which ASes are authorized to originate prefixes.
10 min readLooking Glass & BGP Diagnostic Tools
Learn to use BGP looking glass servers, route collectors, and diagnostic tools to troubleshoot routing issues and verify prefix announcements.
9 min readBGP Communities: Signaling Between Networks
Learn how BGP communities tag routes with metadata to signal routing policy between autonomous systems, with practical examples.
10 min readInternet Exchange Points (IXPs) Explained
Understand how Internet Exchange Points work, why they reduce latency and transit costs, and how networks peer at IXPs.
9 min readBGP Hijacking: Detection and Prevention
Learn how BGP hijacking works, real-world incidents, and the layered defense strategy combining RPKI, IRR filtering, and monitoring.
11 min readBGP Session Troubleshooting Guide
A systematic approach to diagnosing and fixing BGP session problems, from neighbor establishment failures to route propagation issues.
10 min readAS Path Prepending: Traffic Engineering with BGP
Learn how AS path prepending works for inbound traffic engineering, its limitations, and when to use alternative approaches.
9 min readBGP Multipath and ECMP Load Balancing
Learn how BGP multipath and Equal-Cost Multi-Path (ECMP) distribute traffic across multiple links for better bandwidth utilization and redundancy.
9 min readCreating Route Origin Authorizations (ROAs)
A practical guide to creating RPKI ROAs through the five Regional Internet Registries, with best practices for maxLength and monitoring.
9 min readBGP FlowSpec: DDoS Mitigation at the Routing Layer
Learn how BGP FlowSpec distributes traffic filtering rules across your network to mitigate DDoS attacks at line rate without dedicated scrubbing centers.
10 min readBGP Large Communities (RFC 8092)
Understand BGP Large Communities -- the modern replacement for standard communities that supports 4-byte ASNs and richer signaling.
8 min read