Sizing connectivity, power and security communications for a field base

Bandwidth: 22 × 0.30 × 0.25 = 1.65; + 2 × 1.5 = 3.0; + 4 × 0.1 = 0.4; + 0.5 = 5.55 Mbit/s; with a 25% margin: 6.94, i.e. about 7 Mbit/s downlink.

12-month costs: A: 9,500 + 12 × 1,400 = 26,300 USD; B: 2,500 + 12 × 250 = 5,500 USD; C: 3,000 + 12 × 50 × 7 = 7,200 USD.

Suitability: A offers 8 Mbit/s at most, but with 1:4 contention the guaranteed throughput can fall to 2 Mbit/s, below the requirement; the 600 ms latency degrades video conferencing and telephony. B amply covers the requirement with low latency, but its authorisation has not been granted: using it without a licence exposes the organisation to seizure of equipment and sanctions. C is only for essential communications.

Recommendation: B as the primary solution once authorisation is obtained (written confirmation from the regulator and the inter-agency telecoms coordination); until then, A as the primary solution. C as backup in both cases, plus the satellite phones. Cost B + C: 12,700 USD; A + C: 33,500 USD.

Critical load: 75 + 45 + 50 + 40 = 210 W; consumption: 210 × 24 = 5.04 kWh per day.

Panels: 5.04 / (5 × 0.75) = 1.34 kWp; 1.6 kWp is installed (4 panels of 400 W) to allow for dust, the rainy season and degradation.

Battery: 5.04 × 2 = 10.08 kWh usable; 10.08 / 0.8 = 12.6 kWh nominal.

Cost: 1.6 × 1,000 + 12.6 × 450 + 1,800 = 1,600 + 5,670 + 1,800 = 9,070 USD.

The generator remains for office loads (computers, printer) during working hours; critical equipment and radios no longer depend on it, which guarantees security communications at night.

Set-up: VHF repeater on a high point halfway along the route (current coverage only 20 km for an 80 km road); VHF and HF base stations at the base; mobile HF sets in the two vehicles that make long trips; one satellite phone per vehicle on mission (purchase of 2 more); call signs, channels and frequencies coordinated with the inter-agency telecoms group and authorised by the regulator.

Procedures: radio room staffed during all movements; departure call, check-in points every 30 minutes, arrival call; after 30 minutes without contact, search procedure defined in the security plan; daily radio check; end of the use of personal messaging apps for movement tracking.

Budget: connectivity B + C 12,700; solar 9,070; repeater 9,000; 2 satellite phones 1,800 + 2 × 40 × 12 = 960; 2 mobile HF sets 7,000. Total: 40,530 USD, under the 45,000 (margin of 4,470). Equipping all 4 vehicles with HF (14,000) would exceed the budget (47,530): this is a deliberate trade-off.

1. Immediate: declare the theft as a data incident, assess which personal data were on the laptop, inform the data protection focal point and, if necessary, the people concerned.
2. Full disk encryption on all laptops and phones.
3. Individual accounts, end of the shared password, multi-factor authentication, administrator rights reserved for the IT team.
4. Encrypted data collection forms, direct upload to the server and deletion of local data after synchronisation; minimisation of data collected.
5. Backups following the 3-2-1 rule (three copies, two media, one off-site), tested.
6. Remote device management (locking and wiping), staff training and a procedure in case of loss.

A courteous but clear refusal. Sharing our connection with an armed party compromises neutrality and independence, and can make the base a target for other groups. Our network would carry military communications over which we have no control, with a legal risk in relation to the licence. The security of the base relies on acceptance, not on something given in return to an armed actor.

I do not negotiate alone: I inform the head of base and the security manager, who deliver the reply; the request and the reply are documented. I also check that the Wi-Fi network is not open: strong password, separate guest network, disabled.