A California firm sells technology that allows telecoms to detect and block or interfere with VoIP packets entering their networks.

Countries with expensive telecom systems have had to watch as millions of users opt to use VoIP services to make cheap calls online. The IEEE publication Spectrum noted how this has affected countries like Saudi Arabia. More importantly, it reported on how they have started to fight back.

Retaliation comes courtesy of software created by Mountain View, CA-based Narus. Its software can detect and identify VoIP packets traversing the switched telecom network. It can even tell a lot of times which software, like Skype or Vonage, generated the call.

German users will be introduced to Narus soon. Wireless communications giant Vodafone plans to implement the technology there. A French carrier, SFR, intends to do the same, the report said.

In the US, common carrier status prevents telecoms from blocking those calls. But they could use Narus to interfere with VoIP traffic enough to make it “jitter,” Narus’ VP of product marketing said in the article.

Common carriers status doesn’t extend to broadband providers like the country’s largest cable company, Comcast, which is already a Narus customer. Thomas would not say if Comcast was blocking VoIP with Narus software.

The benefit of the Narus product comes to companies that wish to monetize connecting to certain content or with certain devices. Unfortunately, the use of products like Narus endangers the open nature of the Internet:

“Protecting its network is a legitimate thing for a carrier to do,” says Alex Curtis, government affairs manager for Public Knowledge, a consumer-interest advocacy group in Washington, D.C. “But it’s another thing for a Comcast to charge more if I use my own TiVo instead of the personal video recorder they provide, or for Time Warner, which owns CNN, to charge a premium if I want to watch Fox News on my computer.”

“Consumers have come to expect a lot from the Internet-to be able to get to any site, for example, or any service, like VoIP,” Curtis says. “Without Net neutrality, that goes out the window.”

David Utter is a staff writer for webproworld covering technology and business. Email him here.