Selecting the right LPWAN technology requires multi-criteria analysis: payload size constraints can eliminate options entirely (Sigfox’s 12-byte limit), recurring cellular subscriptions dominate TCO at scale (private LoRaWAN saves ~6x over NB-IoT for 50,000 devices over 5 years), and spectrum type (licensed vs. unlicensed) determines interference guarantees and deployment flexibility.
This chapter provides comprehensive assessment scenarios for LPWAN technology selection, including detailed analysis of real-world deployment decisions involving cost, scale, and technical constraints.
This assessment tests your ability to choose the right LPWAN technology for different scenarios. Should you use LoRaWAN, Sigfox, or NB-IoT for a smart agriculture project? The answer depends on factors like range, battery life, data size, and cost. These questions help you practice making informed technology choices.
“A farmer wants soil moisture sensors across 500 hectares. Which LPWAN should she use?” Max the Microcontroller posed the challenge.
Sammy the Sensor analyzed: “The farm is rural, so maybe no cell coverage – that rules out NB-IoT. She needs long range and low power. Soil moisture readings are tiny – a few bytes. Sounds like LoRaWAN with a single gateway on the barn roof!”
“But what if a city wants to track 50,000 parking spots?” asked Lila the LED. “Each spot sends a simple ‘occupied/empty’ message once every few minutes. That’s ultra-simple data from massive numbers of devices – perfect for Sigfox, which handles huge device counts with minimal infrastructure.”
Bella the Battery proposed another scenario: “A fleet of delivery trucks needs to report GPS locations while driving through cities. They need reliable coverage everywhere, even in underground parking garages. NB-IoT wins here – it uses existing cell towers, works indoors, and has the bandwidth for GPS data. Every scenario has a best-fit technology!”
Complex deployment decisions require careful analysis of all constraints.
| Component | Value | Calculation |
|---|---|---|
| TX current | 120 mA | During transmission |
| TX time | 200 ms | 45 bytes at SF7 |
| TX per day | 96 | Every 15 minutes |
| TX energy/day | 0.64 mAh | (120 mA × 0.2 s / 3600 s) × 96 |
| Sleep current | 5 µA | Deep sleep mode |
| Sleep energy/day | 0.12 mAh | (5 µA / 1000) × 24 h |
| Total daily | 0.76 mAh/day | TX + Sleep |
| Battery capacity | 2400 mAh | 2× AA lithium batteries |
| Battery life | 8.6 years | 2400 / (0.76 × 365) |
| vs Requirement | 2.9× margin | Exceeds 3-year requirement |
Summary — Why LoRaWAN is the only viable choice:
The payload constraint alone eliminates Sigfox, making LoRaWAN the only viable LPWAN option for this deployment.
Understanding TCO at scale is critical for enterprise deployments.
Before examining large-scale agricultural deployments, consider how deployment scale interacts with technology choice.
Question: At what deployment scale does private LoRaWAN become more cost-effective than NB-IoT over 10 years?
Given:
Step 1: Calculate cost as function of device count (N)
LoRaWAN Total Cost (10 years):
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Sensors: N × €15
Gateways: (N / 100) × €1,500 [100 devices per gateway at 20 devices/km²]
Network server: €300 × 12 × 10 = €36,000
Maintenance: (N / 100) × €100 × 10
LoRaWAN(N) = 15N + 15(N/100) + 36,000 + (N/100) × 1,000
= 15N + 0.15N + 36,000 + 10N
= 25.15N + 36,000
NB-IoT Total Cost (10 years):
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Sensors: N × €20
Subscription: N × €30 × 10 years
NB-IoT(N) = 20N + 300N = 320NStep 2: Find break-even point
LoRaWAN(N) = NB-IoT(N)
25.15N + 36,000 = 320N
36,000 = 320N - 25.15N
36,000 = 294.85N
N = 122 devices
Break-even: ~122 devicesStep 3: Validate with concrete scenarios
| Devices | LoRaWAN 10-yr Cost | NB-IoT 10-yr Cost | Winner | Savings |
|---|---|---|---|---|
| 100 | €38,515 | €32,000 | NB-IoT | -€6,515 |
| 122 | €39,068 | €39,040 | Break-even | ~€0 |
| 500 | €54,575 | €160,000 | LoRaWAN | €105,425 |
| 1,000 | €61,150 | €320,000 | LoRaWAN | €258,850 |
| 10,000 | €287,500 | €3,200,000 | LoRaWAN | €2,912,500 |
Step 4: Sensitivity analysis
The break-even point varies with:
Gateway cost impact:
- At €500/gateway: Break-even = 82 devices
- At €2,000/gateway: Break-even = 162 devices
Subscription cost impact:
- At €24/year: Break-even = 147 devices
- At €36/year: Break-even = 107 devices
Deployment density impact:
- 10 devices/km² (rural): 200 devices/gateway → Break-even = 98 devices
- 50 devices/km² (urban): 50 devices/gateway → Break-even = 183 devicesKey Insights:
Decision Rules:
Adjust the parameters to find the deployment scale at which private LoRaWAN infrastructure becomes more cost-effective than a per-device cellular subscription.
viewof gw_cost = Inputs.range([500, 3000], {value: 1500, step: 100, label: "Gateway cost (EUR)"})
viewof devices_per_gw = Inputs.range([50, 500], {value: 100, step: 10, label: "Devices per gateway"})
viewof sub_annual = Inputs.range([12, 120], {value: 30, step: 6, label: "Cellular fee (EUR/yr)"})
viewof deploy_years = Inputs.range([3, 15], {value: 10, step: 1, label: "Deployment years"}){
// LoRaWAN cost function: sensors + gateways + network server + maintenance
const lora_sensor = 15;
const nbiot_sensor = 20;
const net_server_annual = 3600; // EUR/yr (300/month)
const gw_maint_annual = 100; // EUR/gateway/year
// Break-even: lora_total(N) = nbiot_total(N)
// lora = lora_sensor*N + (N/devices_per_gw)*gw_cost + net_server_annual*deploy_years + (N/devices_per_gw)*gw_maint_annual*deploy_years
// nbiot = nbiot_sensor*N + sub_annual*N*deploy_years
// Solve for N:
const lora_coeff = lora_sensor + (gw_cost / devices_per_gw) + (gw_maint_annual * deploy_years / devices_per_gw);
const nbiot_coeff = nbiot_sensor + (sub_annual * deploy_years);
const fixed_lora = net_server_annual * deploy_years;
// lora_coeff*N + fixed_lora = nbiot_coeff*N
// N = fixed_lora / (nbiot_coeff - lora_coeff)
const breakeven = Math.max(0, Math.ceil(fixed_lora / (nbiot_coeff - lora_coeff)));
const scenarios = [100, 500, 1000, 5000, 10000];
const rows = scenarios.map(n => {
const lora_cost = lora_coeff * n + fixed_lora;
const nbiot_cost = nbiot_coeff * n;
const winner = lora_cost < nbiot_cost ? "LoRaWAN" : "NB-IoT";
const color = winner === "LoRaWAN" ? "#e8f5e9" : "#fff3e0";
return `<tr style="background:${color}"><td style="padding:5px 8px;">${n.toLocaleString()}</td><td style="padding:5px 8px; text-align:right;">EUR ${lora_cost.toLocaleString(undefined,{maximumFractionDigits:0})}</td><td style="padding:5px 8px; text-align:right;">EUR ${nbiot_cost.toLocaleString(undefined,{maximumFractionDigits:0})}</td><td style="padding:5px 8px; text-align:center;">${winner}</td></tr>`;
}).join('');
return html`<div style="background: var(--bs-light, #f8f9fa); padding: 1rem; border-radius: 8px; border-left: 4px solid #E67E22; margin-top: 0.5rem;">
<p style="margin:0 0 0.5rem 0; color:#2C3E50;"><strong>Break-even: ~${breakeven.toLocaleString()} devices</strong> (${deploy_years}-year deployment)</p>
<table style="width:100%; border-collapse:collapse; font-size:0.9em;">
<tr style="background:#2C3E50; color:white;"><th style="padding:6px 8px; text-align:left;">Devices</th><th style="padding:6px 8px; text-align:right;">LoRaWAN TCO</th><th style="padding:6px 8px; text-align:right;">NB-IoT TCO</th><th style="padding:6px 8px; text-align:center;">Winner</th></tr>
${rows}
</table>
<p style="margin:0.75rem 0 0 0; font-size:0.85em; color:#7F8C8D;">LoRaWAN sensor: EUR ${lora_sensor}, NB-IoT sensor: EUR ${nbiot_sensor}. Green = LoRaWAN cheaper, orange = NB-IoT cheaper.</p>
</div>`;
}This assessment applies multi-criteria decision making to LPWAN technology selection:
Decision Frameworks:
Cost Modeling:
Deployment Patterns:
Technology Constraints:
Application Domains:
Assessment Progression:
Technology Comparisons:
Decision Support:
Application-Specific Guidance:
Learning Tools:
:
This technology selection assessment covered:
Key Takeaways:
| Chapter | Focus | Why Read It |
|---|---|---|
| LPWAN Assessment: Regulatory Compliance | Duty cycle limits, operator risk, and regional regulation | Apply the selection skills from this chapter to regulatory scenarios and evaluate compliance trade-offs |
| LPWAN Assessment: Fundamentals | Core LPWAN protocol concepts and characteristics | Reinforce the foundational parameters (range, bandwidth, spreading factor) that underpin every selection decision |
| LPWAN Comparison and Review | Detailed technology comparison matrices | Examine side-by-side constraint tables for LoRaWAN, Sigfox, NB-IoT, and LTE-M to sharpen your evaluation criteria |
| LoRaWAN Architecture | LoRaWAN network server, gateways, and ADR | Design private LoRaWAN networks with confidence after calculating their TCO advantage |
| NB-IoT Fundamentals | NB-IoT radio, PSM, eDRX, and coverage classes | Understand when cellular IoT justifies its higher cost — guaranteed QoS, roaming, and SLA-backed deployments |
| LPWAN Architectures | Deployment topologies and gateway placement strategies | Translate the break-even analysis into physical network designs for rural and urban environments |