Secure Calls

Phone calls made over the normal telecommunications system have some forms of protection from third party interception, i.e. GSM mobile phones calls are encrypted. GSM calls are not encrypted end-to-end however and telephone providers are increasingly forced to give governments and law enforement organisations access to your calls. In addition to this the encryption used in GSM has been cracked and now anyone with enough interest and capital can buy the equipment to intercept calls. A GSM Interceptor ( is an off the shelf device to record mobile phone conversations when in the vicinity of the call. Centralised or proprietary systems like Skype also encrypt calls but have built in backdoors for secret services and governments and are at the behest of their owner (in Skype's case Microsoft).

A solution to this problem is to make encrypted calls using Voice over IP (VoIP) through an Internet connection. Both WiFi or mobile data networks can be used: cracking the GSM or Wireless password will not mean that your call can be intercepted.

As regards platforms, Android has a wider range of open source VoIP software, largely because Apple's AppStore licensing model prohibits distribution of software released under the General Public License (approximately 60% of all open source software released). The GPL is very popular in the security and networking community.

At the time of writing iPhone users have only non-open-source options available for purchase, like Groundwire ( Warning: as it is not open, the security of Groundwire cannot be assured!

Android users head over to the section Call Encryption to get started making secure VoIP calls.

encs/cph/secure-calls.txt · Poslední úprava: 2013/01/17 20:10 (upraveno mimo DokuWiki)
Kromě míst, kde je explicitně uvedeno jinak, je obsah této wiki licencován pod následující licencí: CC Attribution-Share Alike 3.0 Unported
Recent changes RSS feed Donate Powered by PHP Valid XHTML 1.0 Valid CSS Driven by DokuWiki