olemus
telefonside kasutamise seire ja halduse süsteem
= a system for monitoring and managing telephone communications

ülevaateid
https://www.ringcentral.com/call-management.html
https://www.lawinsider.com/dictionary/call-management-system

näiteid
https://www.bitrix24.com/uses/free-call-management-software-call-management-system.php
http://www.businessnewsdaily.com/6780-best-business-phone-systems.html