The Total Access 604 provides four fixed analog voice interfaces. This analog FXS interfaces support the stringent design and full feature set required by today's carriers. Both systems provide a built-in IP router and an integrated Nx56/64 V.35 port for synchronous data applications, allowing the customer to combine a broad variety of voice and data services into a single platform. The Total Access 604 is compatible with industry leading VoBB Gateways. The FXS interfaces support all popular CLASS features, and an additional Assured Dialtone analog interface is provided for Lifeline POTS.