Server Message Block (SMB) is a protocol that is mainly used by Windows. It allows computers to access or share files, printers, and other network resources remotely. The SMB protocol version 3.0 is a new introduction in Windows Server 2012. The version 3.0 uses the Advanced Encryption Standard (AES) method for encryption and signing.
The use or concept of encryption is not new. However, prior to Windows Server 2012, Internet Protocol Security (IPSEC or IPsec) was the only available option for transferring an encrypted data in Windows. Since the implementation of IPSEC required more administrative effort, configuration changes, and so on, it wasn't widely adopted in the industry. In Windows 2012 server, Microsoft introduced SMB version 3.0, which supports encrypting file, folder, or server. Unlike other encryption mechanisms, the SMB encryption can be enabled without any major implementation or configuration changes.