This paper presents an architecture and implementation of AAL type 2 (AAL2), which is a new ATM adaptation layer for low bit-rate voice transmission over ATM, which has been discussed at the ITU-T and ATM-Forum for standardization. The proposed architecture can be applied to arbitrary codecs, enables cell transfer for multiple VCs, enables control data transfer with AAL type 5, and has a structure that can easily configure the AAL2 function according to the required number of channels. The performance of the proposed architecture is roughly simulated and the results indicate the available number of voice channels for a 2 Mb/s bandwidth is 320 using 8 kb/s codecs with silence compression. The proposed AAL2 function has been achieved wit/i an FPGA array board, which can easily reconfigure the mapping of the logic. The FPGA mapping result indicates that the proposed AAL2 junction with required interfaces for at least 32 voice channels can be implemented by 4 FPGAs and a processor.
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