Security measures Mobile communication systems 7 Mobile computing 6 Wireless communication systems 4 Cell phones 3 Public key infrastructure (Computer security) 3 Access control 2 Cell phone systems 2 Computer networks 2 Computer security 2 Prevention 2 Bluetooth technology 1 Cellular telephone systems 1 Computer algorithms 1 Computer crimes 1 Cryptography 1 Data encryption (Computer science) 1 Electronic funds transfers 1 Equipment and supplies 1 Hackers 1 Instant messaging 1 Internet banking 1 Machine learning 1 Malware (Computer software) 1 Mobile commerce 1 Multicasting (Computer networks) 1 Wireless Internet 1 XML (Document markup language) 1