An EU agent working at the European External Action Service (EEAS) needs to share a confidential document about a mission of the Common Security and Defence Policy (CSDP) with a colleague at an EU seat in another country. The agent is evaluating different digital tools to ensure data security and the integrity of communication, in line with EU data protection and cybersecurity principles. Considering the EU's digital security framework and the sensitive nature of the information, which of the following statements best describes the recommended practice for handling these sensitive data in a collaborative environment?