Cisco 6-port Voice/Fax Expansion ModuleThe Cisco 6 port Voice Fax Expansion Module adds flexible analog voice capabilities to select Cisco Integrated Services Routers (ISRs), enabling direct PSTN connectivity and seamless integration with existing telephony equipment. Designed for a range of deployment scenariosfrom small branches to enterprise edge sitesthis module lets you scale voice and fax services without replacing your core router, preserving investment while expanding capacity and