Used DataCapper for Windows?
Developer’s Description
DataCapper is a broadband datacap monitoring system. It allows users to monitor their internet data usage and supports several different modes of ISP data caps including monthly, daily, overuse charged by the megabyte and peak/off peak mode. The program uses SNMP to gather usage data directly from the modem or router so does not include LAN traffic like most other tools. This requires SNMP Agent support to be enabled through the modem's configuration page. Most modems and routers do support SNMP, but some do not, often the setting is disabled by default. Unfortunately, due to the nature of SNMP and the fact that DataCapper is unlikely to be running at all times, data usage can become inaccurate over time, so an option has been included to manually set the data usage to that provided by the ISP on their usage check page for the user's account.
Version 1.2.1 is a bug fixing release.
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