An AAL design for circuit emulation with signalling function

This paper describes the design of an ASIC called ASAH-A (ATM Subscriber Access Handler-AAL) which is one of the ASAH-series ASICs developed in Electronics and Telecommunications Research Institute (ETRI) in South Korea. The ASAH-A was designed to have AAL Type 1 function for circuit emulation and AAL Type 5 function for signalling. It can provide two channels of DS3, DS1 or E1 services and 2 channels for each signalling service. The designed ASAH-A performs segmentation and reassembly (SAR) functions and convergence sublayer (CS) functions as described in the ATM Forum User-Network Interface (UNI) Specification Ver 3.1, ATM Forum 94-0033R5, and lTU-T 1.363.1. It was also designed to accommodate the cell delay variation (CDV) specification which is recommended in the ATM UNI Ver 3.1. By using internal buffer DS1 or E1 services can be provided with this CDV specification. In addition ASAH-A has an interface for external buffers to provide the flexible implementation for all DS3, DS1, E1 services