Detecting Script-to-Script Interactions in Call Processing Language

Masahide NAKAMURA, Pattara LEELAPRUTE, Ken-ichi MATSUMOTO, and Tohru KIKUNO

Graduate School of Information Science, Nara Institute of Science and Technology, Japan
{masa-n, matumoto}
Graduate School of Information Science and Technology, Osaka University, Japan
{pattara, kikuno}

Abstract. This paper addresses a problem to detect feature interactions in a CPL (Call Processing Language) programmable service environment on Internet telephony. In the CPL environment, the previous works cannot be directly applied, because of new complications introduced:(a) features created by non-experts and (b) distributed feature provision. To cope with the problem (a), we propose eight types of semantic warnings which guarantee some aspects of semantic correctness in each individual CPL script. Then, as for (b), we present an alternative definition of feature interactions, and propose a method to implement run-time feature interaction detection. The key idea is to define feature interactions as the semantic warnings over multiple CPL scripts, each of which is semantically safe. We also demonstrate tools, called CPL checker and FI simulator, to help users to construct reliable CPL scripts.