Hi Zaid,
A couple of links that will help
https://supportforums.cisco.com/discussion/12038081/configuring-vg350-cucm-91
http://www.cisco.com/c/en/us/td/docs/routers/access/vg350/software/configuration/guide/vg350_scg/scgapp_platforms_ORIG.html#pgfId-1098123
Manish