This ability to use two different switching techniques simultaneously means that:

• All traffic is switched with minimum conversion between packet and traditional telephony to provide optimum voice quality in all call scenarios.
• Embedded gateway functionality is only required between the IP and non-IP networks optimizing the use of system resources.
• Migration from traditional PBX to IP telephony is seamless and efficient.
• Feature/functionality between the TDM and IP domain is transparent

The 3300 ICP is built upon Mitel Data Integrated Voice Applications™ architecture delivering sophisticated call management, applications and desktop solutions for businesses. Mitel delivers a highly scalable, resilient, robust call control that fully utilizes the power of IP while fully supporting the traditional TDM based telephony for legacy devices and PSTN connectivity.

Mitel's architecture uses the IP network to connect IP telephony devices and provides a supplementary TDM (Time Division Multiplexing) subsystem to switch calls between traditional telephone devices. The 3300 ICP has the advantage of being able to optimally switch all types of traffic, IP or TDM.

The 3300 ICP provides native call setup, tear down, and signaling between Ethernet IP connected telephones. For traditional telephony, such as POTS and PSTN trunks, call handling is also handled natively by the 3300 ICP via a conventional TDM circuit-switched subsystem.