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The rapid growth of new telecommunications services such as long-distance, cellular, mobile satellite, and personal communications has been driving the development of speech coding technology. However, for speech coding to be economically viable while offering optimum quality, uniformity is required. This uniformity has traditionally being served by standards, which have typically been developed to address network and/or end-user terminal applications. These two different applications often impose different types of requirements that speech coding systems must meet. For example, for network speech coders, emphasis is often placed on transparency to signaling in addition to speech signals. On the other hand, for end-user applications, low complexity is often a crucial requirement while transparency to nonvoice signals is not. Internationally, speech coding standardization activities are addressed by different fora that can be associated with the two types of applications mentioned above. For network applications, the Telecommunications Standardization sector of the International Telecommunications Union and the ANSI Committee T1 on Telecommunications are active in this area. For end-user applications, the US Government, the International Standards Organization, the ANSI Telecommunications Industry Association, and the European Telecommunications Standards' Institute are key players.