Cap usage per period, for example a fixed amount of 2 GB per user per month for, say, $25. If you hit this limit then your data service is disconnected for the rest of that month.
Introduce a higher rate above a certain limit. For instance, the plan may specify that the first gigabyte of data per month is charged a flat rate of $20. Any additional data above that will cost $35 per gigabyte.
Throttling above certain limits. The data provider may state that the first 2 GB of data will be downloaded at unlimited bandwidth speeds. After that, any additional data transmitted will be subject to a maximum of 200 Kbps download and 100 Kbps upload.
