Origination - Flow of Call

Flow of Call

A gatekeeper is an application that receives the registration requests and calls from a dialer. When a user signs in to the dialer, the request goes to the Gatekeeper. The gatekeeper asks the Radius server to see if the username and password are correct and valid. The Radius server queries the database and sends a yes/no reply to the gatekeeper. If authenticated, the user can then make phone calls from the dialer. When the user dials a phone number in the dialer, the request again goes to the gatekeeper, gatekeeper again asks the Radius server if the user is allowed to make this call and has enough money to initiate it. The Radius server asks the billing server for the maximum duration of call that can be allowed to this user based on the amount of money remaining in his account or prepaid card. The billing solution looks up the destination of the call, finds the appropriate rate based on the peak/ off peak hours and the type of the customer and informs the Radius server exact duration in seconds that the user can call to this destination. The same info is returned by the Radius server to the gatekeeper and the gatekeeper informs the dialer the IP address of the destination gateway that can deliver the voice call to the destination. Given this information, the call is initiated if nothing else goes wrong and the two parties can talk. If they continue to talk till the maximum allowed duration of the call, the call is disconnected by the gatekeeper so that the user doesn’t consume any amount above the available limit.

Whenever a call is disconnected naturally or forcefully by the gatekeeper, the gatekeeper informs the billing application with the details of that call. The billing application computes the total call charges and deducts the amount from the calling customer’s account or prepaid card. Termination Requirements.

All VoIP originators require a call termination arrangement with a terminator called VoIP terminator. There are different companies which provide termination to specific destinations and there are others that provide termination to all the destinations. The later are usually called A-Z terminators and are more convenient for beginning companies to work with.