Definition
FMS (Fleet Management System) is a comprehensive system for managing vehicles, drivers, dispatch, fuel consumption, maintenance, insurance, compliance, etc. FMS collects data such as vehicle location, fuel consumption, mileage, fault codes, video, ADAS/DSM alerts through T-Box, in-vehicle terminals, and DVRs, enabling vehicle monitoring, dispatch optimization, cost analysis, driving behavior analysis, safety warnings, electronic waybills, and more.
FMS integrates with systems like TMS, ERP, and WMS to form complete supply chain and fleet management. IoT SIM cards provide connectivity for FMS in-vehicle terminals, DVRs, ADAS, DSM, and other devices, forming the basis for fleet data collection, with high requirements for network stability, coverage, and data usage.
Technical Features
FMS supports real-time positioning, geofencing, route planning, fuel consumption analysis, driving behavior scoring, maintenance reminders, insurance integration, and more. When combined with video surveillance, ADAS, and DSM, it can achieve proactive safety management. It supports multi-tenant, multi-fleet, and multi-brand vehicle access.
Use Cases
FMS is applied to logistics fleets, express delivery, passenger transport, taxis, ride-hailing, rental vehicles, and the 'two passengers and one dangerous' sectors. Typical scenarios include vehicle dispatch, location tracking, fuel management, driving behavior analysis, ADAS warnings, fatigue monitoring, electronic waybills, and compliance management. SimtoLink provides in-vehicle IoT SIM cards, dedicated APN, high-volume data plans, and connected vehicle solutions for FMS scenarios.
Splitting Location Heartbeats from Video
What the SIM connection means to the fleet platform
In a fleet system, the IoT SIM is the wide-area identity of the vehicle terminal. Location points, fuel or energy use, mileage, fault codes, and short video needed as evidence all leave the vehicle on that SIM. "Vehicle online" on the platform often means only that the location heartbeat is still arriving. It does not mean the video path, the dispatch receipt, and the electronic waybill succeeded on the same link. Split the meaning: a heartbeat proves the terminal is still registered, and a service message proves the status of this trip has been handed to the platform. They may share a SIM number. They should not share a send buffer with no priority.
Driver identity, roster, and maintenance plans are kept on the platform. The SIM does not know who is driving. What it can show is whether vehicle-side communication is available, which plan the traffic falls into, and whether attach is still allowed while roaming. If active-safety alerts are analyzed on the vehicle, the SIM uploads the conclusion and a short piece of evidence. If raw video is streamed for a long time, the plan and the weak network fail before the algorithm does. The boundary with driver assistance is covered under ADAS. Fleet dispatch still rests on the waybill and the position. An assistance alert cannot replace an arrival confirmation.
Conditions for tunnels and cross-border sections
Conditions follow where the vehicle works. City delivery can be planned on the local network. Line-haul, ports, and cross-border coaches must have roaming opened in advance, or an access method that can switch, and they must allow offline cache in tunnels, underground depots, and metal containers. Location points should be saved locally with timestamps and backfilled in order after the tunnel, not reduced to "the current point," which erases the track in between. Video uploads only on an alert or a manual request. At other times, keep the heartbeat and the events.
When one vehicle has several terminals, the locator, the recorder, and the dispatch screen may be different SIMs. The ledger has to bind plate, terminal serial, and SIM number, or the fuel curve and the video do not belong to the same vehicle. Suspension policy should follow the fleet, not a personal account, so a driver's unpaid bill does not remove the whole vehicle from monitoring.
Video upload crowding out live location
A common failure is an alert video and the location packets fighting over one link. In weak coverage the video retry fills the buffer, the vehicle on the platform sits at a position from half an hour ago, and dispatch thinks that is live. Another is no cache in the tunnel, then only the newest coordinate after exit, so the track becomes a straight line on the map and both mileage and the geofence are wrong. After a border policy suspends the SIM, the terminal still records locally, the platform shows silence, and the gap is found only when the vehicle returns.
Putting a test vehicle's SIM into an operating vehicle, with the wrong plan and allow-list, shows up as online one moment and authentication failure the next. A heartbeat set too often drives the data pool to abnormal usage, and the real video request then hits the cap. Acceptance, while the vehicle is moving, should watch the location interval, whether one short alert video succeeds, and whether location points still arrive on their original interval while that video is uploading.
When a driver changes vehicle, or a tractor changes trailer, the track is recorded on whichever terminal the SIM follows. If the platform treats the SIM number as the plate, dropping a trailer breaks the track, or fuel is charged to the wrong tractor. The binding should be the plate or the asset number. The SIM number is the current means of communication. A SIM change or a terminal change updates the means. It does not create a new vehicle. If an electronic waybill's start and end depend on a geofence, the geofence should use the historical points after backfill, not only the "current online point." Otherwise an entry or exit inside a tunnel is erased and the waybill stays "not arrived." The clock for video evidence and the clock for location points must be the same set. A difference of a few minutes will not match that braking event in a dispute. Before a SIM is suspended for non-payment, warn fleet dispatch. Do not cut it off directly, or a whole fleet disappears from the map on the same billing day.