Understanding physical circuit traces is considered a fundamental skill for hackers moving into Software-Defined PBX systems.
In the world of telecommunications security (or "phreaking"), the motherboard of a PBX serves as the central nervous system for a business's internal phone network. Hacking these boards typically involves identifying physical vulnerabilities to intercept or manipulate calls. pbx hacking motherboard
Let me clarify:
Security researchers often target the motherboard to extract the firmware controlling the PBX. pbx hacking motherboard