Local bus

This article is about computer local buses

"processor local bus" redirects here. For IBM's PLB, see CoreConnect.

Not to be confused with a type of bus service.

In computer architecture, a local bus is a computer bus that connects directly, or almost directly, from the central processing unit (CPU) to one or more slots on the expansion bus. The significance of direct connection to the CPU is avoiding the bottleneck created by the expansion bus, thus providing fast throughput. There are several local buses built into various types of computers to increase the speed of data transfer (i.e. bandwidth). Local buses for expanded memory and video boards are the most common. VESA Local Bus is an example of a local bus design.

Although VL-Bus was later succeeded by AGP, it is not correct to categorize AGP as a local bus. Whereas VL-Bus operated on the CPU's memory bus at the CPU's clock speed, an AGP peripheral runs at specified clock speeds that run independently of the CPU clock (usually using a divider of the CPU clock). The concept of Local Bus was pioneered by Dado Banatao.