[Sip-implementors] Ongoing Billing Information

[Christian Stredicke]

Hey SIP fans,   we have an increasing number of people who would like to start SIP services for MONEY (big surprise!). They would like to sell calling cards with a number of “coins”. We have two problems:   1) Is there a method to indicate how many “coins” are left? I could think of a NOTIFY which is sent to the phone and it can display that in addition to the call time etc or play a little beep when another coin has been used.   2) When the number of coins goes down to zero, these operators would like to STOP the call immediately. My proposal would be using session timer for this and change the credentials on the proxy when the coins are used up. Then the next re-invite would fail and the call is over.   When the call is stopped by “out of coins”, the call needs to be redirected to a media server that says “sorry you are bankrupt”. I think this can be done using Error-Info.   Doing this proprietary is obviously no big deal. Question: Are there any drafts (RFC?) out there dealing with this problem?`   Christian -- Christian Stredicke sip:[EMAIL PROTECTED]