AAC systems have a flexible, modular architecture that allows you to choose the most cost-effective service for each application and manage them all from a single platform. The AAC-3 has seven user slots that can be filled with modules of your choice. Each slot contains a protocol module that determines the traffic type (cell, CBR, packet, or Ethernet) and a physical layer module that determines the physical interface. The high port density and modular architecture lets you grow and upgrade your network at a minimal cost. As your service or application needs change, you only switch modules, keeping a common chassis and management interface.