What is USSD?
Unstructured Supplementary Services Data (USSD) is a session-oriented GSM service that provides users with access to (mainly) data services. A service is requested by sending a code beginning with a * and ending with a #. Requesting the Nokia firmware version may be done by keying in *#0000#. The code will then be routed via the signalling channel (SS7) by the (international) mobile network to the HLR (Home Location Register). There, the application is activated via the code and the result of the application is sent back to the mobile screen. The message cannot be stored, which is possible in case of an SMS. USSD is supported by all mobile telephones.

Why USSD?
USSD has been in existence since the beginning of the first GSM networks and is still in operation in existing 3G/HSDPA networks. The advantage of the USSD is that it uses the signalling channel (SS7). As a result, most services are free, and international roaming is also possible. The applications can therefore also be used abroad.
There are 2 phases of USSD, Phase 1 consists of a question and answer, while a dialog may be developed in Phase 2.
Known USSD applications are:
• Requesting prepaid balance
• Recharging prepaid balance
• Voting
• Text services, such as:
• Weather
• Information
• Lottery
• Media
• Shops
• Sport
• Travel

Why Comsys USSD?
In the last 25 years, Comsys has acquired a great deal of experience in speech and data services. Both in terms of creating and offering solutions as well as hosted services. On the basis of this experience, Comsys has developed the latest generation speech and data platform under the name ‘SpeechFrame’.

SpeechFrame uses VoiceXML to achieve a maximum level of user convenience and flexibility. It can be used in converging voice, web and mobile services, and also offers speech recognition (ASR) and Text-to-Speech (TTS).

Additional features:
• It is based on JAVA, Web technology and VoiceXML;
• It is redundant and scalable, and offers a guaranteed performance;
• It offers dynamic dialogue;
• It distinguishes itself through short developmental processes;
• It can be integrated with web services;
• It offers database connectivity;
• It can be easily integrated with: CTI, CRM and ERP.