WASHINGTON, Feb. 26 (UPI) -- Pakistani authorities' efforts to block access to the video-sharing Web site YouTube from Internet addresses in their own country effectively shut down the site altogether at the weekend, disrupting access to it by would-be visitors from all over the world.
The outage, which appears to have been the result of an error, blocked traffic to the site for about two hours Sunday, and experts say it demonstrates the fragile quality of the Internet, which is a network based largely on trust.
On Friday, the Pakistan Telecommunications Authority, the country's telecom regulator, ordered Internet service providers in Pakistan to block access to a YouTube video -- a trailer for a controversial film about the Koran being made by Dutch politician Geert Wilders.
A statement from the authority said the decision was taken following a meeting of senior officials from several Pakistani ministries, including telecommunications, information and broadcasting, interior and religious affairs.
The statement called the trailer "highly provocative and blasphemous," adding that it "absolutely stands against the values of religious tolerance and peaceful coexistence" and was "arousing deep anguish and distress across the Muslim world."
The authority had blocked the site, the statement concluded, to forestall "more unrest and possible loss of life and property across the country."
But experts say the method used to block the site by at least one ISP leaked into the Internet, causing traffic to YouTube to be directed into a kind of Web cul-de-sac in Pakistan.
A YouTube statement e-mailed to United Press International confirmed the cause of the outage, and that it had originated in Pakistan.
"Traffic to YouTube was routed according to erroneous Internet protocols, and many users around the world could not access our site," read the statement.
"We have determined that the source of these events was a network in Pakistan," the statement continued. "We are investigating and working with others in the Internet community to prevent this from happening again."
Marcus Sachs, director of the Internet Storm Center run by the non-profit SANS Institute, told UPI the outage was a byproduct of the open architecture of the Internet and the way in which Web traffic is routed from server to server.
"This looks like a mistake by a router engineer," said Sachs, saying the error occurred when a "local announcement to computers using one ISP … leaked out somehow and was propagated across the Internet generally."
The announcement was in the form of routing information provided under the so-called Border Gateway Protocol. BGP tables, Sachs said, provide information to computers about how to connect to Internet addresses their users want to visit.
To block YouTube, said Daniel Castro of the Information Technology and Innovation Foundation, one ISP, Pakistan Telecommunication Corp. Ltd., essentially placed false information in its BGP tables, diverting customers trying to access YouTube into a kind of Internet dead end.
But the false routing information was picked up by a large telecommunications company that provides network services to PCTL and distributed around the Internet.
"This has happened before," said Castro, adding, "Usually it doesn't happen because usually you don't have a major ISP deliberately putting false information out there."
"The Internet only works," said Sachs, "because of the enormous amount of trust involved." He added that there were security implications.
"Imagine if this had happened to a bank or a utility provider or any other Web site providing a critical service," he said.
Castro noted: "We've seen a pattern of other countries blocking YouTube," most recently Turkey, but also Brazil, China, Iran, Morocco, Myanmar, Syria and Thailand in the last few years.
"We see this as in some ways a free-trade issue," said Castro. "If you are blocking this service (from users in your country) effectively you are giving preferences to other (Web sites providing the same) service."
Wilders' 10-minute film, titled "Fitna" ("Ordeal" in Arabic), which he plans to release next month, will show how the Muslim holy book "is an inspiration for intolerance, murder and terror," he said recently.
By Monday, YouTube had removed the video trailer, saying it had violated the site's terms of use, which include a prohibition on "hate speech," defined as "speech which attacks or demeans a group based on race or ethnic origin, religion, disability, gender, age, veteran status, and sexual orientation/gender identity."
A YouTube spokesman did not respond to a request for an interview, and the company has in the past said it would not comment about the decision to remove material for terms of use violations.
Anonymous officials from the Pakistan Telecommunications Authority told several news outlets they had also cut off access to other Web sites showing the controversial Danish newspaper cartoons of the Prophet Mohammad. They were originally printed in 2006 but were reprinted by some European newspapers last week.
