The Migration of the Optical Internetworking Forum Common Electrical Interface Standardization to Optical Intra-System Interconnects beyond 25 Gbps

Abstract: There has been a decade long history of groundbreaking work on Common Electrical Interface (CEI) Implementation Agreements within the Optical Internetworking Forum (OIF). While the first edition of CEI specifications was dedicated to 6 Gbps and 11 Gbps serial electrical interfaces, later revisions address a range of applications encompassing 20 - 28 Gbps rates involving various classes of reach, with recent initiatives targeted at doubling these rates. This article discusses the evolution of OIF CEI specification development, including the impacts of critical elements like, for example, channel models, signaling schemes, and power consumption of the required Serdes designs. It provides an overview of current active work areas that are focusing upon 28 Gbps and 56 Gbps serial electrical interfaces and their relevance to some of the latest 100G - 400G line card and system developments. Finally, it offers a projection of ongoing OIF work regarding the Next Generation Interconnect (NGI) framework project, which is starting to define a transition path from electrical to optical intra-system interconnects for even higher serial data rates and longer reaches.