Automatic Line Switching

Khelifi, A., Symons, C.R., Abran, A.

The Automatic Line Switching system is documented in the ISO technical report:
ISO/IEC TR 14143-4 (Version 2000). This ISO document provides various sets of
Functional User Requirements (FUR), described usually in a textual formal. The purpose
of this ISO document is to provide to researchers and practitioners with sets of
requirements to be used as publicly available documents for measuring the functional
size of software.

The Automatic Line Switching system used in this case study corresponds to set RUR B.8
of this ISO document. This set RUR B.8 documents the requirements for a real-time
system to switch between a Work Line and a Backup Line which are provided for a
communication channel: if the Work Line degrades or fails the Backup Line is used


in Real-time Case Studies