Codec playback performance is one of the greatest challenges in designing an Internet-based delivery model for television. Different hardware manufacturers use widely varying levels of support for their playback devices to save marginally on unit cost. Encoding systems can obtain much better quality if the receiving unit has sufficient performance. Therefore, InterStream is considering publishing a specification for minimum standards used in the net-top playback system. Personal computers are more problematic since they may have very different video cards and drivers providing widely varying performance.