ARCHIVED: What is Server Message Block (SMB)?

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Server Message Block (SMB) is the Internet standard protocol Windows uses to share files, printers, and serial ports. In a networked environment, servers make file systems and resources available to clients. Clients make SMB requests for resources, and servers make SMB responses in what's described as a client server, request-response protocol.

The SMB protocol can be used over the Internet on top of its TCP/IP protocol or on top of other network protocols. Using the SMB protocol, an application (or the user of an application) can access files at a remote server, as well as other resources, including printers. Thus, a client application can read, create, and update files on the remote server. It can also communicate with any server program that is set up to receive an SMB client request.

Microsoft Windows operating systems since Windows 95 include client and server SMB protocol support. For Unix type systems, like Linux and Mac OS X, an open source application called Samba is available which, when installed and properly configured, allows SMB interoperability between those operating systems and Windows.

This information was adapted from Microsoft TechNet and Whatis.com.