Server Message Block (SMB)

The Server Message Block (SMB) is a network protocol that allows the host to share data within the same network. It shares directories, files, printers, and serial ports as quickly as on the local computer. It is a request-response protocol that uses TCP port 445 for communication. All the messages of the Server Message Block protocol have a standard format: a fixed-sized header with a variable size parameter and a data component.

The Server Message Block protocol suite is comparatively easy. It includes commands for resource operation that you might do on a local disk or printer, such as:

  • Creating new files and directories
  • Deleting files and directories
  • Opening and closing files
  • Searching for files and directories
  • Reading, writing, and editing files
  • Queuing and de-queuing files in a print spool

The Server Message Block servers make the file systems and resources available to the clients in the network. The clients make SMB requests for the available resources on the server using the commands, and the servers create Server Message Block response messages. The following are the SMB message types:-

·         Initiate, authenticate, and terminate the sessions

·         Control access to file and printer

·         Allow to send and receive messages using the application

File sharing and printer sharing are both primary services of Microsoft networking. With the release of Windows 2000, Microsoft changed the original structure for using SMB. Before Windows 2000, the Server Message Block services used a non-TCP/IP protocol to execute name resolution, but after Windows 2000, all Microsoft products use DNS naming, which allows TCP/IP protocols to support SMB resource sharing. The figure below illustrates the establishment of the SMB protocol connection.

SMB

Using the Server Message Block, once the connection is established, the client user can reach the resources on the remote end as if the resource were local to the client host.

Although the Server Message Block protocol was initially created for Windows, it can now also be used by Linux, Unix, and Mac OSX, using software called Samba. Samba, Linux, Mac, Windows, and Unix computers can share duplicate files, folders, and printers.

What does SMB stand for in business? SMB, or Server Message Block, is a network protocol used in business settings to share files, printers, and other resources in a networked setting.