Definition
Station electronic fences and entry-exit auditing refers to enclosed or semi-enclosed stations such as port yards, express distribution centers, and hazardous chemical storage. Using geographic boundaries (polygon fences, berth sub-areas, lane corridors) as the rule carrier, the entry, exit, abnormal stop, and business events (appointments, weigh bills, loading/unloading completion) of vehicles/trailers are associated to form a searchable, reconcilable, and evidentiary entry-exit timeline.
The positioning can integrate GNSS, base station assistance, and in-station RFID/ground sensor/barrier gate signals; license plate recognition (LPR), weighing, and access control data are used for cross-verification to reduce false alarms caused by 'trajectory drift, cloned plates, and tailgating through barriers.' Besides real-time alerts, the platform side should also retain original traces, rule versions, and operation logs to meet internal control, cargo damage disputes, and regulatory spot checks.
- Fence types: full boundary, loading/unloading area, waiting area, no-parking zone, and temporary control area, which can come with time-based policies.
- Audit objects: vehicle number/trailer number, driver or escort identity, entry/exit timestamps, duration of stay, associated work order or waybill number.
- Abnormal models: overtime stay, entry/exit during unauthorized periods, route deviation, blacklisted vehicles approaching sensitive parking spots, etc.
Technical Features
Commonly coexisting on the link are high-frequency position points, event-type messages (barrier passage, alerts), and video/image backhaul with high volume. Weak networks, roaming, and in-station metal obstruction may cause positioning jitter; smoothing, geographic matching, and 'last known valid pose' caching are recommended at the edge. On the video side, adopt hierarchical bitrate, event-triggered uploads, and offline retransmission to avoid occupying critical signaling.
The platform can output KPIs for security and operations: turnaround time, berth utilization, blacklist hits, alert closure time. Rule and fence versions should be incorporated into change management: who released, when it takes effect, how to roll back, to avoid platform discrepancies after on-site parameter changes. The time source is recommended to be unified (NTP/GNSS), and attention should be paid to time zones and daylight saving boundaries when reconciling across systems.
- Fusion Criteria: Fence events + barrier/LPR + (if applicable) weighbridge, reducing false alarms from a single source.
- Evidence Chain: SIM/device identifier, firmware version, rule version, and original message hash all retained together.
- Security: Remote maintenance channels isolated from production data plane; parameter issuance requires authentication and auditing.
Use Cases
Applicable to port yards, express distribution centers, hazardous chemical warehouses, cold chain parks, logistics gates within large manufacturing plants, and other scenarios requiring a closed loop of "who, when, where, and how long." When interfacing with TMS, WMS, appointment queuing, electronic seals, or insurance risk control, entry and exit audits often serve as key evidence for the handover of cargo rights and liability division.
SimtoLink can provide manageable and controllable cellular access and policy templates (multiple APNs, data pool, SIM-card binding) for station gateways, onboard terminals, and edge video boxes, facilitating unified activation and visible costs when replicating across multiple sites.
Key points for cooperation with IoT SIM cards
During acceptance, distinguish "dial/attachment success" from "business transaction success": aside from card status, it is recommended to sample-verify DNS, TLS, business ports under long connections, weak network reconnections, and roaming switches, and retain end-to-end samples for troubleshooting comparison.
- Data Plan and Channels: Position and events use low-traffic channels; video/OTA and large logs are segregated into separate pools or off-peak windows, with threshold alarms set.
- Network Strategy: Evaluate private APN, fixed exit IP, whitelisted domains, and roaming policies to meet platform and campus firewall requirements.
- Asset Ledger: ICCID, IMEI, gate/car equipment number, installation point binding; silent cards and abnormal traffic enter the work order closed loop.
- Reliability: Key gates can consider dual SIMs with dual carriers or cellular + wired primary/backup; SLA stipulates online rate, reporting success rate, and latency percentiles.
- Compliance: Collect sensitive data such as license plate and facial information on a minimal necessary basis, clarify retention period, access audit, and third-party sharing boundaries.