A communication layer, Flexible Optical Service Unit (OSUFlex), to provide small service channels in optical transport networks is specified in this standard. The main features of the OSUflex communication layer are providing massive OSUflex connections to directly carry power services (e.g., E1 or IEEE Std C37.94™) into an optical transport network, enabling the flexible bandwidth (e.g., n x 2 Mb/s) and hitless bandwidth adjustment for each OSUflex connection, direct mapping of services into OSUflex with the capabilities of high-bandwidth efficiency, low latency, low latency jitter, and high-precision clock synchronization for power system applications.

This standard specifies a communication layer, Flexible Optical Service Unit (OSUFlex), to provide small service channels in optical transport networks. The main features of the OSUFlex communication layer are providing massive OSUflex connections to directly carry power services (e.g., E1 or IEEE Std C37.94) into the optical transport network, enabling the flexible bandwidth (e.g., n ×2 Mbit/s) and hitless bandwidth adjustment for each OSUflex connection, directly mapping of service into OSUflex with the capabilities of high bandwidth efficiency, low latency, low latency jitter, and high-precision clock synchronization for power system applications.

The standard supports mass transport of mission-critical services (teleprotection, remote terminal units, supervisory control, data acquisition, etc.) that are used in electrical power (smart) grids. The standard meets the communication requirements of electrical power system applications in terms of bandwidth, efficiency, low latency, low latency jitter, and high-precision clock synchronization.