FREMONT, Calif., Oct. 12 -- Three documents describing specific improvements in the cost-effectiveness and flexibility of optical networking interfaces have been approved by the Optical Internetworking Forum (OIF). The documents cover electrical interfaces, low-cost optical interfaces and signaling protocols. The approval of these three documents is significant in that it brings the optical networking industry one step closer to having a standardized specification for key network components, said Russ Tuck, chairman of OIF's Physical & Link Layer Working Group. Acceptance of a standardized specification for optical network interfaces will ensure that compatible parts will be available from multiple vendors. That added flexibility will improve time-to-market for new products and will lower system costs. The documents submitted by OIF's Physical & Link Layer Working Group include SPI-3 specification for interfaces within routers in OC-48 bandwidth applications, SPI-4 Phase 1 specification for interfaces within routers in 10 Gb/s bandwidth applications, and SFI-4 electrical interface specification for the transfer of data between STS-192/STM-64 framers and the Serializer/Deserializer.