CREST Practitioner Security Analyst (CPSA) 2025 – 400 Free Practice Questions to Pass the Exam

The correct answer is Jabber, which operates on port 5222. Jabber is an open-source protocol based on Extensible Messaging and Presence Protocol (XMPP), facilitating instant messaging and presence information communication. It is widely used for chat applications, allowing real-time communication and social networking.

Port 5222 is designated specifically for client-to-server communication using the XMPP protocol, making it essential for establishing connections between Jabber clients (users' applications) and servers. This allows users to send and receive messages, manage presence, and interact with other Jabber users.

In contrast, the other protocols listed do not operate on this port; FTP (File Transfer Protocol) typically uses ports 20 and 21 for file transfer functions, IMAP (Internet Message Access Protocol) usually operates on port 143 for email retrieval, and SMTP (Simple Mail Transfer Protocol) conventionally uses port 25 for sending emails. Each of these protocols serves different purposes and operates on different ports, underscoring the unique role of the Jabber protocol in the realm of instant messaging and presence management.