Motorola Solutions' DIMETRA TETRA infrastructure utilizes the TETRA radio communication protocol, essential for European public safety, rail, and military networks. Relying on proprietary testing frameworks, the company seeks to modernize its testing processes. This research analyzes the feasibility of migrating the DIMETRA Zone Controller (ZC) testing from the legacy Generic Link Simulator (GLS) to the modern Java-based Marion framework. The study evaluates efficiency, maintainability, cost, and ease of migration to recommend a framework aligned with Motorola Solutions' long-term goals. GLS, a specialized tool designed for ZC testing, offers efficient packet handling and a simple syntax, but suffers from limitations in code maintainability, extensibility, and the absence of modern software engineering practices.