a2billing has three basic ways to authenticate users when they reach the platform. CallerID, accountcode and PIN/Card Number.

By the default, the system will not prompt for the Card ID Number if:

• The call comes from a SIP or IAX device that can authenticate to the system (VoIP authentication). a2billing knows that the call comes from a legitimate device because it can find in the customer database the correspondent accountcode.

• The call comes from a VoIP terminal or other type of trunk technology that sends a customer associated CallerID. The usage of CallerID is necessary to provide automatic identification/authentication for users coming from PSTN/ISDN lines.

If CallerID or accountcode authentication does not take place, the user is requested to introduce the PIN number (Card Number/Account Number). It is important to notice that CallerID based-authentication is more insecure that a SIP or IAX2 challenge-response authentication.

Note: In a2billing, Customer, User, Account Number, Card Number or PIN number are the same thing :-)