Via Voice over VoIP services: PTA can't block incoming global calls

Pakistan Telecommunication Authority (PTA) does not have the necessary equipment to block international incoming calls via Voice over Internet Protocol (VoIP) services but can block specific telephone numbers. PTA, if instructed, can only block anti-Pakistan calls if they come through a specific telephone number but cannot block calls if VoIP services-Skype, Viber, Whatsapp, Twitter, Tango-as are used, said senior officials of Pakistan Telecommunication Authority (PTA) and Federal Investigation Agency (FIA) on condition of anonymity.
Voice over IP, VoIP and IP telephony is a methodology and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet. Rehman Malik former Interior Minister said that Pakistan has the capacity to intercept calls, messages and emails but blocking anyone's calls is a difficult task. He added that calls could be blocked via vice recognition equipment.
The PTA has banned the website of the Muttahida Qaumi Movement (MQM) on instructions from the federal government. A PTA official confirmed that the Authority had received orders from the federal government to block the IP addresses hosting the MQM website. The site is inaccessible in Pakistan only.
After MQM offices across Karachi and other cities were sealed by orders, it now seems likely that MQM may face further restrictions and a ban on VoIP use, sources said. According to a legal expert, Article 17(2) of the Constitution of Pakistan could be imposed following MQM chief's anti-Pakistan and inciting violence speech.
The expert further claimed that without imposition of Article 17(2), the sealing of the party's offices and ban on VoIP use is challengeable in a court of law as the MQM leader has been indicted but not yet convicted of any crime. Article 17 of the Constitution proclaims the freedom of association and forming political parties as a fundamental right guaranteed to the citizens, whereas clause (2) places the power to impose reasonable restrictions on said rights given they act against the state.
On October 3, 2013, the Sindh government had decided to ban instant messaging and VoIP for three months in the province for security reasons. An IT expert said that while the government can ban YouTube, Facebook or Bollywood films with an 'anti-Pakistan' theme, yet the state cannot really block a site as it is impossible in the era of global internet to truly stop access to any information.