Should have worked on:
1. IP based Call Center.
2. Dial Plan in Asterisk.
3. Good understanding of VXML and IVR development.
4. Good understanding of VoIP, SIP, SS7.
5. Prior working on voice cards, media gateway, WebRTC etc.
6. Expert in Freepbx
7. Understanding of Telephony, CCXML,VXML, json - Scripting skills (Perl/Shell etc.) - Understanding of Linux/Unix commands/distributions (RHEL,CentOS,Fedora)
8. Expert in Cisco voip along will get priority