PLEX is an acronym for Programming Language for EXchanges and is a highlevel language developed by Ericsson in the 1970s.
PLEX is a high-level, real-time, language with very strict requirements regarding execution time.
– High Level: A high-level programming language uses commands independent of the processor type. High-level commands are general, and usually translate into several different instructions at the machine level.
– Single-purpose: PLEX is a programming language designed exclusively for telephony systems. It therefore lacks common statements from other programming languages such as WHILE loops, negative numeric values or real numbers. These elements are not needed in telephony.
– Real-Time: Telephony software must execute as fast as possible. Programs have to meet certain time limits specified by customers and align with key Standards.