Telecommunication systems Computer networks 119 Digital communications 71 Telecommunication 69 Management 49 Design and construction 45 Information technology 44 Signal processing 42 Computers 37 Data transmission systems 34 Computer simulation 32 System analysis 30 Internetworking (Telecommunication) 29 Wireless communication systems 24 Data processing 21 Optical communications 21 Mathematical models 19 Mobile communication systems 19 Communication systems 16 Local area networks (Computer networks) 15 Security measures 15 Telephone switching systems, Electronic 15 Simulation methods 14 Equipment and supplies 13 Evaluation 13 Fiber optics 13 Planning 13 Programmable controllers 13 Technological innovations 13 Computer security 12