Error detection and correction options for data services in B-ISDN

The authors investigate error detection and correction options for data services in the broadband integrated services digital network (B-ISDN). They discuss and analyze different options for error detection and correction by considering the various alternatives ranging from no error protection to only error detection. Based on the analysis and results presented, a per-cell cyclic redundancy check (CRC) has been adopted in the adaptation layer for all data services. The authors focus on the ATM (asynchronous transfer mode) adaptation layer (AAL) error protection alternatives available within the framework of a per-cell CRC. The ATM cell header and AAL fields are described. A 4 bit cell sequence number for detecting cell misordering is analyzed. Based on the analysis, it is concluded that the 4 bit sequence number provides a powerful capability for detection of cell misordering