Abstract: Techniques for applying FEC to optical signals such as synchronous transport signal level N SONET frames, as well as other frame structures (e.g., synchronous transport module level N SDH frames) are provided.

Abstract: A bridge or other transparent layer-two device uses a simple protocol to filter duplicate frames and learn about nodes connected to a bridged local area network. Using the simple protocol, the bridge or other layer-two device does not need to run a Spanning Tree algorithm.

Abstract: Disclosed is an error-correction method and apparatus for transmission of block-based coding standard compliant video data, such as H.263, MPEG or JPEG. A picture is divided into slices wherein each slice of the picture is coded into a group of blocks (GOB) in which each macroblock in the GOB is encoded only with reference to other macroblocks in the same GOB. An erasure slice, which is also a GOB, is then formed wherein the data for each macroblock of the erasure slice is determined by summing a corresponding macroblock in each of the GOBs containing slices of the picture. The GOBs containing slices of the picture are then transmitted, along with the GOB containing the erasure slice, as block-based coding standard compliant data packets. The result is that if any one of the GOBs containing slices of the picture is lost, then the lost GOB can be reconstructed from the remaining GOBs and the erasure slice.