In this paper, in order to develop the transmission system between the remote subscriber and the central office, the hardware and software implementation of a SMUX(Statistical Multiplexer)which can interleace eleven 16Kbps D-channels over a 64Kbps B-channel is obtained. As a result of this study, the high speed data transmission by the use of a dynamic buffer memory management algofithm for statistical multiplexing is realized. Especially a software architectur for interruption is proposed in order to improve performance of the transmission system more efficiently.