Which technology uses digital certificates for secure communications over the Internet?

An FQDN (Fully Qualified Domain Name) is a complete domain name for a specific host on the internet and does not inherently provide security or use digital certificates.

Internet Service Manager (ISM) is typically a management console for IIS (Internet Information Services) and is not a security technology that uses digital certificates for communication itself.

Secure Sockets Layer (SSL), and its successor Transport Layer Security (TLS), uses digital certificates to authenticate the server to the client and to encrypt the communication session. When a client connects to an SSL/TLS-enabled server, the server presents its digital certificate, which contains its public key, allowing the client to verify the server's identity and establish a secure, encrypted connection.

FTP (File Transfer Protocol) is an older protocol for transferring files and does not inherently provide secure communication using digital certificates; secure versions like FTPS or SFTP are needed for that.