BGP Origin Hijacking: The 2008 BGP YouTube Outage from Pakistan to the world
Preface: In February 2008 the world saw just how fragile and interconnected the Internet routing system is when Pakistan’s attempt to block YouTube locally ended up taking YouTube down globally. The Pakistani government asked local ISPs to block YouTube due to content, and Pakistan Telecom (AS17557) did so by announcing a false BGP route for YouTube’s IP prefix. This was meant to be a local announcement only but was accidentally propagated to the global Internet by their upstream provider PCCW (AS3491) who accepted and further announced the bogus route to other networks. Since BGP favors the most specific prefix, networks around the world started sending YouTube traffic to Pakistan Telecom and a massive black hole effect took YouTube down for users worldwide. This is often referred to as one of the biggest BGP hijacking incidents in history and showed the trust-based vulnerabilities in BGP, the lack of built in route authentication and the importance of implementing stronger s...