internet telephony

Internet Telephony



odd (2) land-line at odds with
switch regulate voice-over IP
encrypt content at some point
on par admit (2) stream (2)
hack forensic loudspeaker
route average compress
victim standard playback
seldom proof (2) implement
provide negotiate prosecutor
bug (2) exception impossible
secure exchange intelligence
privacy demand automatic


Video: Internet Telephony


Hannelore Kucher is at odds with her telecom service provider. The company wants to switch her land-line to voice-over IP, saying it’s cheaper for both businesses and their customers.

But she says the change is unnecessary.

Hannelore Kucher: “I have to have my telephone on my computer and watch TV on my computer. Those are things we don’t need.”

She’ll have to make the change at some point because all over the world, providers are backing internet telephony.

Phone calls now run compressed as data streams over the internet.

In Germany, 29% of all the phone calls are made via the internet, which is on par with the world average.

Bulgaria and Lithuania rank higher with almost 60%.

But voice-over IP is not secure.

Michael Vogt is a computer forensic specialist in Hamburg. He shows how easy it is to hack a call. All he needs is a computer program and an IP address.

With the click of the mouse, Vogt orders both telephones to send their signals to his computer first.

Michael Vogt: “Victims and the people they’re calling don’t notice that all their communication is routed through my computer. And if the communication isn’t encrypted, I can ultimately hear all of it.”

A test proves it: the technician can hear both sides of the entire conversation.

Vogt: “One side comes out of the left loudspeaker, the other from the right — and we hit playback . . . Now we hear what the receptionist said.”

Phoning by the internet could actually be completely bug-proof. End-to-end encryption could protect personal privacy.

It’s technically possible, but seldom implemented.

Data protection officer, Thilo Weichert, says he knows why.

Thilo Weichert: “One reason is that security authorities — police, public prosecutors’ offices and intelligence services — want to listen in themselves if necessary. And with end-to-end encryption, that’s impossible, or at least very difficult.”

Confidential papers from a European regulation agency show that secret services is actively involved in negotiating new standards. They include German, Canadian, British and American intelligence agencies.

The result is that European phone conversations are not automatically encrypted.

What that means can be seen at the Institute of Internet Security in Gensenkirchen: the university’s voice-over IP is under attack from all over the world.

University IT Expert: “We’re attacked every single minute. We constantly get warnings and security alerts. You can see on our monitor just when a hacking attack has started.”

Until now, encryption has been the exception. Deutsche Telecomm say that at some point content should be end-to-end encrypted.

And Vodafone admits that through encrypted communication, security can be additionally increased.

Thilo Weichert: “Our demand is that the telecom providers generally encrypt their exchange of telecommunication — especially telephony.”

Until that happens, voice-over IP remains unencrypted and unsafe.

“SHIFT says, ‘protect personal privacy’.”

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1. What does Ms. Kucher telecom provider want her to do? Why do they want to do that?

2. Landline is the old way to transmit phone calls, and voice-over IP is the new way. True or false? is the voice-over IP is superior to the old land-line system in every way? Is voice-over IP perfect?

3. Because Bulgaria and Lithuania are poorer than Western Europe, do they mostly use landline services?

4. It is technically possible to bug-proof voice-over IP phone calls. Is this right or wrong?

5. If it is possible to have end-to-end encryption, why isn’t it implemented to function automatically?

6. The university’s system is hacked every minute. Why are people hacking it?

7. What does the telecommunications expert want to see in the future?

A. Describe your telephone system. Has it changed over time?

B. How do you feel about someone eavesdropping on your phone calls?

C. There should be end-to-end encryption on all internet telephony. Do you agree?

D. What advice can you give to people? What should people do?

E. What will happen in the future?

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