SS7, or Signaling System #7, is a set of signaling protocols used for telephone communication worldwide. It replaced older in-band signaling technology and made new services available to subscribers. SS7 is compatible with online phone services and VoIP for international calls.
While the term SS7 is commonly used in the United States, it is not an accepted acronym worldwide. Here are some facts about the nature, function and applications of SS7 technology around the world including the other names of the system.
With a proper name of Signaling System #7, SS7 technology is a set of signaling protocols developed specifically for telephone communication protocols. Originally developed by AT&T in 1975, these protocols now provide the foundation for public switched telephone networks around the world. The name used to identify the protocols varied from place to place. For example, SS7 technology is known simply as C7 in the UK, CCSS7 in other parts of North America, and more recently as ITU-T in other parts of the world.
SS7 was originally designed to replace older signaling technology which was starting to experience more failures as the demand for voice communications continued to increase worldwide. With earlier versions of signaling protocols, the basis was an in-band signaling process, where the setup process for initiating calls was triggered by the sounding of special tones in the lines. Referred to as carrier channels, this older technology became problematic as tone technology led people to discover that they could bypass the special keys used by operators to initiate these protocols. Devices that could emit a series of tones and then strike a working combination were starting to get a bit confusing and in some cases would overwhelm an already busy communications network.
SS7 technology solved both problems at the same time. By switching to out-of-band, secure signaling protocols, it was no longer possible to emulate tones to trigger telephony activity. This effectively eliminated the hijacking of telephone channels and freed up the communications network to process legitimate requests for voice communications. The expansion into out-of-band tones also made possible the expansion of telephone networks in a number of countries, as new channels could be added as needed.
SS7 has also made a whole series of new services available to telephone subscribers. For example, many of us are used to using asterisk commands
to redial a last number, check for a dial tone or access a mailbox. The creation of SS7 also resulted in a variety of support services that customers of various audio conferencing offices can enjoy, such as the ability to call a participant, report operator assistance, initiate a recording, and a list of other options that help control the conference.
With the coming together of voice communications and the Internet, SS7 has proven to be perfectly compatible with online phone service options, enabling the so-called switch to a dedicated service without any hassle. In other words, someone using Internet phone service is still able to call someone using traditional landline services, with no degradation in sound clarity. This is possible thanks to the SS7 protocols, as well as the growing use of VoIP (Voice over Internet Protocol) to process international telephone calls.
Protect your devices with Threat Protection by NordVPN
