The dialplan is the routing core of an Asterisk server. Its sole role is to look at what is dialed, and route the call to its destination. This is the core of any telephony system and Asterisk is no different. VXI* VoiceXML browser for Asterisk provide to the PBX a new function called vxml() to extend your favorite telephony system with VoiceXML 2.0+ execution. VXI* provide dynamic XML programming services thru HTTP / HTTPS and using PHP, ASP, JSP, PERL, Python, CGI, C#, etc… to create and run advanced web enabled speech applications on your Asterisk. The dialplan is made up of three elements: extensions, contexts, and priorities. An extension is number or pattern that the dialed number is to be matched against and a context is a collection of extensions (and possibly other included contexts too).