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SMB Protocol

Webopedia Staff
Last Updated June 23, 2021 7:06 am

SMB can refer to:

Server Message Block

In computer networking, Server Message Block (SMB) is a communication protocol that enables users to share files, directories, devices, and other resources using DOS and Windows. It was first launched by IBM in 1983, but subsequent versions were developed by Microsoft to improve performance and security. In 1996, Microsoft unsuccessfully attempted to rename SMB to Common Internet File System (CIFS), and all future versions were simply identified by its version number (SMBvX.x).

SMB is a response-request protocol that operates in the application layer. It uses port 445 on TCP/IP to facilitate communication between devices on the same network. In current environments, the NetBIOS API and many network products are based on the SMB format including all Windows operating systems since Windows 95. Samba, an open source SMB implementation released in 1992, expanded SMB capabilities to Mac OS X and UNIX-based operating systems.

Small-to-Medium Business

Small-to-medium businesses (SMB), also called small-to-midsize or small and medium businesses, are enterprises that have an employee count or annual revenue below a specified threshold according to the business’s industry or physical location. In the United States, small businesses are widely considered those that have fewer than 100 employees, and medium businesses are those that have between 100 and 999 employees. Small businesses can also be categorized as those that have less than $50 million in annual revenue, and medium businesses can be categorized as those that earn at least $50 million but less than $1 billion annually.

SMBs usually operate on limited budgets, staff, and resources. As such, the challenges SMBs face are different from those of larger enterprises. Small-to-medium business owners are primarily concerned with budget management maximizing profits, minimizing costs, and doing more with fewer resources available. SMBs outnumber large enterprises in most cases, and many government institutions offer special benefits and incentives to help SMBs stay afloat.