Abstract: Recently a series of telecommunications companies together with computer hardware/software companies (Sun, IBM) committed their efforts for building abstractions from multivendor, multiprotocol telephony devices and protocols. These efforts materialized into various products and standards. Most recently the PARLAY group published a set of recommendations called the PARLAY APIs. Sun introduced a JAVA environment with a set of APIs for Integrated Networks called JAIN (pending publication), and IBM produced the JSLEE server, which integrates the JAIN and JCC classes of Sun in an automated Java environment for the implementation of telephony based applications.