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I am on a quota-based internet where I am. I have a USB 3G modem that plugs into my TP-Link MR3420. My quota is being drained quickly, but only my wife and I connects to this router and during the day I am out at work. Wife is not a power user either she only uses Instagram, Facebook, Whatsapp, BBM, and some email and general browsing. Yesterday suddenly more than 1GB was drained when I wasnt home. I installed Data Usage app on our iPhones and none used that much. So either someone is stealing my internet or the ISP is cheating me. I looked through the Wifi connection list and didnt see anything suspicious.
What can I do to know exactly what goes between our devices, router, internet? I am hoping to find something that can tell me exactly which device connected to what server, up/download how many KB, and at what time.
Appreciate your help