One of the more exciting connectivity standards over the past year has been CXL. Built upon a PCIe physical foundation, CXL is a connectivity standard designed to handle much more than what PCIe does – aside from simply acting as a data transfer from host to device, CXL has three branches to support, known as IO, Cache, and Memory. As defined in the CXL 1.0 and 1.1 standards, these three form the basis of a new way to connect a host with a device. The new CXL 2.0 standard takes it a step further.
CXL 2.0 is still built upon the same PCIe 5.0 physical standard, which means that there aren’t any updates in bandwidth or latency, but adds some much needed functionality that customers are used to with PCIe. At the core of CXL 2.0 are the same CXL.io, CXL.cache and CXL.memory intrinsics, dealing with how data is processed and in what context, but with added switching capabilities, added encryption, and support for persistent memory.
