An indexed file layout, comprising index information, is defined for segmented streaming of multimedia content. The index information can comprise program description information and streaming segment index information. In addition, the layout can comprise files containing streaming segments of the program, where the streaming segments are each encoded at one or more bitrates independently of other streaming segments of the program. The layout supports client switching between different bitrates at segment boundaries. Optimized client-side rate control of streaming content can be provided by defining a plurality of states, selecting available paths based on constraint conditions, and selecting a best path through the states (e.g., based on a distortion measure). In one client-side rate control solution states correspond to a specific bitrate of a specific streaming segment, and in another client-side rate control solution states correspond to a measure of client buffer fullness.