The SAI specification was submitted to OCP this week, thanks to the efforts of Dell, Big Switch Networks, Mellanox and Microsoft. SAI is an abstraction layer for switches, that can enables a common API interface across network operating systems.
OCP already has multiple specifications including the Open Network Install Environment (ONIE) which enables different vendor operating systems to run on the same hardware device. Subi Krishnamurthy, CTO, Dell Networking explained that SAI and ONIE are not directly inter-related, but are separate technologies.
From a technology perspective, Krishnamurthy explained that at this point SAI functions by mainly abstracting switch ASICs.
“The SAI provides another layer between the OS and physical silicon on the switch,” Krishnamurthy said. “As a result, programmers don’t have to worry about tailoring networking OS code for each of the many different brands of networking silicon and instead, they can now focus more on the unique needs of differing customers.”