You are the CIO of the Central Intelligence Agency. You must secure the communications, data (in transit and at rest), protect the networks from attacks, intrusion, malware, data exfiltration, DDOS, DNS hijacking, etc. You are in charge of the networks and desktops/laptops/mobile devices use by the 24,000 CIA employees. Besides the critical employees working at the CIA HQ in Langley, VA, you have more than 10,000 employees working from their homes during this pandemic and another 5,000 foreign, undercover agents deployed globally. You, as the CIO of the agency are in charge of cybersecurity of the entire electronic communications, networks, emails, etc. Required:
For the 5000 global undercover agents, how would you secure the communications from their devices to the CIA servers/Other users so it can't be eavesdropped on by foreign intelligence services, and how can you make sure the communications comes from the intended sender and can only be opened only by the intended recipient?