What is Avaya? It is a comprehensive key for the communication requirements of Businesses. It can accommodate extensions ranging from 2 to 360 for home-based offices, sole- proprietors agencies, and networked organizations. It has full-voice functionality with a wide range of features. You can configure the system as a voice-only PBX. You can link multiple systems using SDN (Standard Data Network), and this feature has been implemented in many Call Centers. The SDN capabilities involve Internet or Intranet based routing and has security with Firewall protection. Several Add-Ins like Messaging, Web-Conferencing, etc., can be included. Automated messages route your calls to concerned persons.