Those around the world who had trouble accessing YouTube on Sunday may be interested to know the cause of the problem: On Friday, the Pakistani Telecommunications Authority acted to block access to YouTube in order to prevent Pakistanis from seeing a YouTube clip promoting an anti-Islam film by Dutch politician Geert Wilders (pictured). Thus ensued an accidental chain reaction that blocked YouTube access for many thousands internationally. Now, the popular site is back up, even in Pakistan.
The Wall Street Journal:
But in a bizarre twist, the government’s efforts to block the clip in Pakistan wound up affecting YouTube users around the world. YouTube spokesman Ricardo Reyes confirmed in an email that YouTube traffic was disrupted world-wide for several hours Sunday. “We have determined that the source of these events was a network in Pakistan,” said Mr. Reyes. “We are investigating and working with others in the Internet community to prevent this from happening again.”
The problem began when Pakistan Telecommunication Corp. Ltd. began implementing government orders to block the Dutch video on YouTube, according to people familiar with PTCL’s network operations. The telecommunications company, Pakistan’s largest, controls almost all of the nation’s network infrastructure. The instructions sent out across its network were meant to apply only to traffic within Pakistan, a process commonly known as “black holing.” But because of errors in the handling of PTCL’s routers, the message started being replicated on the Internet world-wide, and other Internet-service providers started having trouble accessing the YouTube site.
The message was communicated around the world via PCCW Ltd., a Hong Kong telecommunications company that inadvertently transmitted the message internationally over its network. PTCL is connected to the global Internet through PCCW’s networks, among others. Technical experts say this type of problem is extremely rare—and is essentially beyond YouTube’s control.
“The traffic that was supposed to be going to our address was being rerouted to Pakistan, and subsequently dropping,” says Mr. Reyes of YouTube.