YouTube Pushed Off the Air: Routing Gone Rogue
While you were watching cat videos or scrolling through Facebook, the UK economy was busy generating $1.93 billion a year in output—that’s £550,000 every two and a half hours. But today, if it were a workday, our collective output would have been a tad higher. Why? Because, for a brief, chaotic moment, Pakistan Telecom accidentally booted YouTube off the internet.
In a wild two-and-a-half-hour BGP routing misadventure, Pakistan Telecom managed to hide YouTube from most of the world. What happened? Let’s dive in.
How Pakistan Telecom Accidentally Took Down YouTube
Earlier today, the Pakistan government reportedly instructed ISPs to block YouTube in the country due to controversial content. Pakistan Telecom, however, took things a step further. They didn’t just block YouTube locally—they accidentally broadcast a route claiming YouTube’s IP range as their own. This announcement spread far and wide, redirecting YouTube-bound traffic to Pakistan instead.
Here’s how it works: the Border Gateway Protocol (BGP), which underpins global internet routing, loves specificity. If a network announces a more "specific" group of IP addresses, BGP prioritises it. For example, if I announce a network with 1,024 addresses, but someone else announces a subset of 256 from that range, their announcement takes precedence. It’s a feature, not a bug—designed to optimise routing. But when someone injects fake routes (whether intentionally or not), the consequences can range from mildly inconvenient to catastrophic.
Pakistan Telecom tried to use this feature to block YouTube domestically. They inserted a route into their own network for a subset of YouTube's addresses. It was intended to block YouTube within the administrative domain of the Pakistan Telecom network only. This route accidentally "leaked" beyond Pakistan, via a insecure filters at their upstream ISP, PCCW Global, spreading to ISPs worldwide. And just like that, YouTube was off the air.
Can We Prevent This?
Small networks and end sites can reduce the risk of leaking bad routes by explicitly defining the network prefixes they plan to announce to their peers and upstream providers. But for larger networks, the picture is more complex. Many have contractual obligations to propagate their customers’ announcements. Add political pressure, human error, or both, and mistakes become more likely—especially when engineers are scrambling to implement rushed decisions from government ministers.
The Bigger Threat: Silent Traffic Hijacking
What happened today was loud and obvious. YouTube would have noticed something was wrong almost immediately, as their traffic disappeared into nothingness in Pakistan. But what if the hijack wasn’t so blatant?
Imagine this: a malicious actor hijacks your IP range, proxies your traffic, and sends it back to you after tampering with it. Your website or network will probably still function, but sensitive data—like customer behaviour or checkout information—could be quietly siphoned away. The impact on e-commerce could be devastating, especially if you’re unaware it’s happening.
The Solution: Securing BGP
The root of the problem lies in the routing protocol itself. BGP wasn’t designed with security in mind, and that’s where efforts like S/BGP (Secure BGP) come in. S/BGP integrates public key infrastructure (PKI) into routing announcements. Essentially, you’d sign your announcements, and your peers could verify them against an impartial internet registry.
If S/BGP were widely adopted, ISPs would’ve been able to spot Pakistan Telecom’s rogue announcement and reject it, saving YouTube from its unintended vacation. While adoption of these technologies remains slow, they represent a vital step forward in protecting the global routing infrastructure from accidents—and more sinister threats.
Today’s YouTube incident serves as a reminder that the internet, while miraculous, is far from bulletproof. Routing errors like this one highlight the importance of robust security measures, transparency, and collaboration across the network. Let’s hope the future brings more secure systems—and fewer moments where we collectively wonder why YouTube has disappeared.