Technical features and pit avoidance experience of WiFi network billing system for payment of micro-mails

Last year, when they gave a technical assessment to a team working on WiFi's campus, their CTO asked a particularly real question:"How can we solve the problem of our WiFi network billing system, which is always connected to payment systems, either by paying for a successful payment but not activated by the user or by paying for a record that cannot be traced by the financial system?"I have taken a look at the problems he has encountered and found that they are not really their problem, as almost all of the teams that built WiFi's own system of billing have stepped on similar pits to pay for the docking.

When WiFi's network billing system was connected to micro-mail, payment bonds, most people were concerned about the interface not being switched, whether it could be successfully initiated and whether it could receive a callback. But in practice, this thinking is problematic.——The interface is only the first step of a long journey and the real solution is the reliability of the return.

What is called a callback reliability? That's if the payout platform gets 100% of the return notice, and you handle it correctly. There are more holes in this than most people think. I've seen one case: operators' web exits occasionally fluctuate for seconds, and we send a call that doesn't arrive. The micro-payment default will be retested, but there are limited and frequent intervals. If your WiFi network billing system does not have a mechanism to actively search the order status, it will always be stuck with passive calls."Pending payment"The user's money was withheld but WiFi was not activated and had to make a phone call.

The standard approach to this problem is a two-tier system: callback notifications are the first line of defence, and regular active queries are the second one. Each order that has been confiscated for more than five minutes to return, WiFi’s network billing system should be proactive in paying for the payment platform query status.

There's also a particularly problematic place to pay for the docking, which is a set of food maps. A definition is found in WiFi's network billing system."Thirty bucks for the monthly card.", the amount of payment requests is 3000.00, but the actual payments returned in the return of a treasure or micro-mail may be 28.50 due to various coupons, red bags, random stubs. What will your system do at this point?

There is no standard answer to this, but your WiFi network billing system must have a clear rule. I've seen two ways in the project: one is strictly converted to the actual amount paid, and how long it takes; the other is that when you pay successfully, you start with the set-show, the difference being either platform subsidy or marketing budget. Both are reasonable, but either way, rules must be written down in the system, so that operators cannot handle them manually every time they meet.

WiFi's payment docking has a frequently forgotten link.——Financial reconciliation. Many people feel that reconciliation is a matter for the financial system and has nothing to do with the billing system. But, in fact, the consistency of daily reconciliation results directly determines the level of trust that the operating team has in the system.

A suitable WiFi network billing system should have at least a daily automatic reconciliation function: order data for this system and billing data for payment platforms are compared by strip, with discrepancies marked and reconciliation reports generated. If done manually, the work can be handled when small, and if orders fall 100 times per day, the cost of manual reconciliations will increase rapidly.

Refunds and disputes are inevitable as long as they involve online payments. WiFi’s network billing system does not simply change the order status to a simple one when processing refunds."Refunds"First, to notify either RADIUS or NAS of the disconnection of the corresponding user session; and secondly, to convert the refunds proportionately based on the length of time used.

The second point is particularly easy to make. For example, users buy a month’s card and demand refund after three days. If your billing system can only refund the full amount or not, it is neither reasonable nor regulatoryly compliant.——However, the conversion formula is defined in advance and requires clear rules for natural days or 24 hours as a unit, and can be reflected in financial reconciliations.

Finally, security. The WiFi network billing system interfaces with the payment system with several safety thresholds that are absolutely unbreakable: the payback interface must be HTTPS, a signature must be verified, a value check (preventes the amount from being tampered with), and a peg like this (the same order number cannot be activated twice). These are routine security measures, but any omission of one of these items in the actual project would pose a serious accident risk, which is very difficult to recover if something happens. Payment matching is essentially money-related, and it is very low for things to do with money. A complaint mail, a microblogging exposure, and a huge difference in the reconciliation can cause irreversible loss of trust in business in a short time. Instead of fighting fires around the world after being reached, the system design phase should see and put into place the dual insurance mechanism, the set-mapping rules, the reconciliation process and the refund processing logic.