capabilities of legacy messaging infrastructure. Limitation In an effort to limit telemarketers who had taken to bombarding users with hordes of unsolicited messages, India introduced new regulations in September 2011, including a cap of 3,000 SMS messages per subscriber per month, or an average of 100 per subscriber per day. Due to representations received from some of the service providers and consumers, TRAI (Telecom Regulatory Authority of India) has raised this limit to 200 SMS messages per SIM per day in case of prepaid services, and up to 6,000 SMS messages per SIM per month in case of postpaid services with effect from November 1, 2011. However, it was ruled unconstitutional by the Delhi high court, but there are some limitations. Flash SMS A Flash SMS is a type of SMS that appears directly on the main screen without user interaction and is not automatically stored in the inbox. It can be useful in emergencies, such as a fire alarm or cases of confidentiality, as in delivering one-time passwords. Silent SMS In 2010 Germany, almost half a million "silent SMS" messages were sent by the federal police, customs and the secret service "Verfassungsschutz" (offices for protection of the constitution). These silent messages, also known as "silent TMS", "stealth SMS", "stealth ping" or "Short Message Type 0", are used to locate a person and thus to create a complete movement profile. They do not show up on a display, nor trigger any acoustical signal when received. Their primary purpose was to deliver special services of the network operator to any cell phone. See also Process driven messaging service Comparison of mobile phone standards Instant messaging Text messaging Thumbing GSM 03.40 Data Coding Scheme Enhanced Messaging Service (EMS) Multimedia Messaging Service (MMS) Rich Communication Services (RCS) Short Message Service Center (SMSC) Short message service technical realisation (GSM) SMS gateway (sending text to or from devices other than phones) SMS hubbing SMS home routing SMS language References External links 3GPP – the organization that maintains the SMS specification ISO Standards (In Zip file format) GSM 03.38 to Unicode – how the GSM 7-bit default alphabet characters map into Unicode 3GPP standards Mobile telecommunication services Mobile telecommunications standards Text messaging Finnish inventions Mobile phones Communication