Level 3 offers both SIP trunking and Integrated Services for Digital Network (ISDN) services in a package known as Voice Complete. Businesses can use Level 3 SIP trunking to connect calls between VoIP systems and the traditional phone network. Level 3 offers broadband Internet for businesses that want a fully managed connection to SIP trunking services, but existing connections can also be used.
Time-dimension multiplexing (TDM) is a technology that sends digital information over the traditional phone network instead of the Internet. Companies that are migrating to VoIP systems from legacy phone systems based on TDM can get TDM services such as ISDN for their legacy systems and SIP trunking service for their VoIP systems.
Voice Complete is certified to work with major platforms, such as Cisco and Avaya, and ensures interoperability between phone systems from different certified vendors. End users can control features and administrators can configure settings in real-time through Web portals. Level 3 also offers access to detailed call logs to help with billing and support.