In 1996, Microsoft launched an initiative to rename SMB to Common Internet File System (CIFS) and added more features, including support for symbolic links, hard links, larger file sizes, and an initial attempt to support direct connections over TCP port 445 without requiring NetBIOS as a transport (a largely experimental effort that required further refinement).īy Microsoft Windows 2000, Microsoft had changed SMB to operate over port 445. Microsoft merged the SMB protocol with their LAN Manager product that it started developing in 1990 and continues to add features to the protocol in Windows for Workgroups. Software applications that run on a NetBIOS session service locate and identify each other via their NetBIOS names over TCP port 139. SMB was originally designed by Barry Feigenbaum at IBM in 1983 with the aim of turning DOS INT 21h local file access into a networked file system and was originally designed to run on top of NetBIOS over TCP/IP (NBT) using IP port 139 and UDP ports 137 and 138. This means a user of the application can open, read, move, create, and update files on the remote server. Once connected, it enables users or applications to make requests to a file server and access resources like printer sharing, mail slots, and named pipes on the remote server. This protocol facilitates file shares between networked computers. This is known as a response-request protocol. SMB works through a client-server approach, where a client makes specific requests and the server responds accordingly. In short, the SMB protocol is a way for computers to talk to each other. It can also carry transaction protocols for authenticated inter-process communication.

The Server Message Block Protocol (SMB Protocol) is a client-server communication protocol used for sharing access to files, printers, serial ports, and data on a network.

Serial sibe mamnue 139