SNA

networking

Stands for: Systems Network Architecture (IBM)

IBM's mainframe networking architecture - the hierarchical world that predated and long coexisted with TCP/IP in the enterprise.

Systems Network Architecture (1974) defined how terminals and controllers reached IBM mainframes, in a rigid hierarchy centered on the host (VTAM). Its link layer was SDLC. For decades SNA and TCP/IP ran side by side in banks and large enterprises, bridged and tunneled (DLSw) as IP won; later APPN added peer routing. Knowing SNA explains a great deal about why enterprise networking evolved the way it did, and about the IBM gear that shaped the industry.

Also known as: sna, systems network architecture, appn, vtam

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