A big telematics data system for determining network communication faults comprising: at least one remote device (19, 20), a plurality of mobile devices and a network comprising network zones, each mobile device of the plurality of mobile devices being associated with a vehicle and including a positional device for indicating a position thereof, each mobile device of the plurality of mobile devices being configured to communicate over the network with the at least one remote device (19, 20) such that a communication comprises communicating at least one of a signal, data or message including a position indication for said each mobile device; each mobile device of the plurality of mobile devices being further configured to determine an expected communication period for communicating with the at least one remote device (19, 20), such that a determination comprises determining an active state or inactive state for said each mobile device, wherein the active state provides a first expected communication with the at least one remote device (19, 20) within a first communication period and the inactive state provides a second expected communication with the at least one remote device (19, 20) within a second communication period; the at least one remote device (19, 20) including a remote device communication fault determination logic configured to determine a communication fault within a time frame, such that determining a communication fault within a time frame comprises determining the total number of expected communications based upon the first and second expected communications for each of the plurality of mobile devices, and comparing, within said time frame, the total number of the expected communications with the actual number of communications from each of the plurality of mobile devices, and determining a fault when the total number of actual communications is different from the total number of expected communications, wherein the remote device communication fault determination logic is further configured to determine a location of the fault within one of the network zones based upon a last known position indication of a mobile device of said plurality of mobile devices having said fault. at least one remote device (19, 20), a plurality of mobile devices and a network comprising network zones, each mobile device of the plurality of mobile devices being associated with a vehicle and including a positional device for indicating a position thereof, each mobile device of the plurality of mobile devices being configured to communicate over the network with the at least one remote device (19, 20) such that a communication comprises communicating at least one of a signal, data or message including a position indication for said each mobile device; each mobile device of the plurality of mobile devices being further configured to determine an expected communication period for communicating with the at least one remote device (19, 20), such that a determination comprises determining an active state or inactive state for said each mobile device, wherein the active state provides a first expected communication with the at least one remote device (19, 20) within a first communication period and the inactive state provides a second expected communication with the at least one remote device (19, 20) within a second communication period; the at least one remote device (19, 20) including a remote device communication fault determination logic configured to determine a communication fault within a time frame, such that determining a communication fault within a time frame comprises determining the total number of expected communications based upon the first and second expected communications for each of the plurality of mobile devices, and comparing, within said time frame, the total number of the expected communications with the actual number of communications from each of the plurality of mobile devices, and determining a fault when the total number of actual communications is different from the total number of expected communications, wherein the remote device communication fault determination logic is further configured to determine a location of the fault within one of the network zones based upon a last known position indication of a mobile device of said plurality of mobile devices having said fault.