High Quality Content by WIKIPEDIA articles! SCI, for Scalable Coherent Interface, is a high-speed interconnect standard for shared memory multiprocessing and message passing. The IEEE Std 1596-1992, IEEE Standard for Scalable Coherent Interface (SCI) was approved by the IEEE standards board on March 19, 1992. The goal was to create an interconnect that would scale well, provide system-wide coherency and a simple interface; i.e. a standard to replace buses in multiprocessor systems without the inherent scalability and performance limitations of buses. The working group soon realized that any form of buses would not suffice and came up with the idea of using point-to-point communication in the form of insertion rings as the right way to go. This approach avoids the lumped capacitance, limited physical length/speed of light problems and stub reflections in addition to allowing parallel transactions. The use of insertion rings is credited to Manolis Katevenis who suggested it at one of the early meetings of the working group. The working group for developing the standard was led by David B. Gustavsson (chair) and David V. James (Vice Chair).