1123  Sigfox: Operator Risks and Infrastructure Dependency

1123.1 Learning Objectives

By the end of this chapter, you will be able to:

  • Evaluate Operator Risks: Understand infrastructure dependency and coverage changes
  • Analyze Coverage Degradation: Diagnose message success rate drops over time
  • Compare Deployment Models: Evaluate operator-managed vs self-deployed networks
  • Assess Long-term Viability: Plan for technology transitions and sunset scenarios
  • Design for Resilience: Build redundancy into LPWAN deployments

1123.2 Prerequisites

Required Chapters: - Sigfox Fundamentals - Core Sigfox concepts - Sigfox Architecture - Network structure - Sigfox Review - Overview and quizzes

Technical Background: - Ultra-narrowband modulation basics - Global network architecture concepts - Duty cycle limitations

Estimated Time: 20 minutes

1123.3 The Operator-Managed Model

Time: ~10 min | Difficulty: Intermediate | Unit: P09.C12.U01

Sigfox’s fundamental architectural choice is the operator-only infrastructure model. Unlike LoRaWAN where users can deploy their own gateways, Sigfox requires all base stations to be operated by licensed Sigfox Network Operators (SNOs).

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graph TB
    subgraph Sigfox["Sigfox Architecture"]
        D1[Your Devices] --> BS1[Operator Base Station]
        BS1 --> SB[Sigfox Backend<br/>Operator Owned]
        SB --> APP1[Your Application]
    end

    subgraph LoRaWAN["LoRaWAN Architecture"]
        D2[Your Devices] --> GW[Your Gateway]
        GW --> NS[Your Network Server]
        NS --> APP2[Your Application]
    end

    style BS1 fill:#E67E22
    style SB fill:#E67E22
    style GW fill:#16A085
    style NS fill:#16A085

Figure 1123.1: Sigfox (orange) uses operator-owned infrastructure with zero user control, while LoRaWAN (teal) allows private network deployment with full user control.

Key Characteristics of Operator Model:

Aspect Sigfox (Operator) LoRaWAN (Private)
Base Station Ownership SNO User
Coverage Control None Full
CapEx Required None Gateway purchases
Monthly Fees Per-device subscription None (after CapEx)
Deployment Timeline Instant (if coverage exists) 1-2 weeks per gateway
Maintenance Operator handles User responsibility

1123.4 Coverage Degradation Risk

The Myth: “Once Sigfox coverage exists in my region, I can rely on it for 10+ year deployments without worrying about network changes.”

The Reality: Sigfox operator economics can cause significant coverage degradation over time, impacting deployed devices without warning.

Real-World Data:

Case Study: European Smart Water Metering (5,000 devices)

Year 1 Performance:
- Message success rate: 98%
- Average RSSI: -105 dBm (strong signal)
- Base stations: 8 covering city
- Cost: EUR5,000/month subscriptions

Year 3 Reality Check:
- Message success rate: 65% (33% DROP!)
- Average RSSI: -125 dBm (weak signal)
- Base stations: 3 remaining (5 decommissioned, 62.5% reduction)
- Cost: Still EUR5,000/month (no refund for degraded service)

Why This Happens:

Operator Economic Pressure:

Initial Deployment (Land Grab Phase):
- 8 base stations x EUR10k capex = EUR80k investment
- Maintenance: EUR16k/month operational cost
- Revenue: EUR500/month (100 early adopters x EUR5)
- Burn rate: -EUR15.5k/month (investor funded, unsustainable)

Post-Deployment Optimization (Year 3):
- Remove "redundant" stations: 8 -> 3 (save EUR10k/month maintenance)
- Maintenance cost reduced: EUR16k -> EUR6k/month
- Revenue grew: EUR5k/month (1000 subscribers x EUR5)
- Now profitable: -EUR1k/month (break-even targeted)
- BUT: Coverage quality dropped 33%!

Quantified Impact: - 33% message loss = 33% of water meter readings lost - No SLA compensation = customers still pay full subscription - Zero user control = cannot add base stations independently - Detection lag = 3-6 months before pattern noticed in logs

1123.5 Understanding Check: Diagnosing Network Degradation

Scenario: Your city deployed 500 Sigfox parking sensors across downtown. Year 1 performance was excellent: 98% message delivery, averaging 4 messages/hour per sensor.

Year 3 Reality: - Message success rate dropped to 65% (33% decline) - Same sensors, same batteries (still 3.4V), same firmware - Network shows uplink count unchanged (still 4 messages/hour attempted) - RSSI values in backend logs dropped from -105 dBm to -125 dBm average

Your Investigation:

  1. Battery analysis: Voltage still healthy at 3.4V (started at 3.6V). Transmission power only drops 5-10% with this voltage change. Cannot explain 33% message loss.

  2. Regulatory check: EU 1% duty cycle unchanged since Year 1. Parking sensors use 0.0056% (200ms/hour), well under limit. No enforcement changes.

  3. Protocol verification: Sigfox protocol backward-compatible. If protocol changed, would see 100% failure, not 65% success rate.

  4. Coverage audit: Check Sigfox operator portal. Discover base station count dropped from 8 stations (Year 1) to 3 stations (Year 3).

Root Cause Discovery:

Operator economic pressure:

Year 1: Land-grab phase
- 8 base stations x $10k capex = $80k
- Maintenance: $16k/month
- Subscriber revenue: $500/month
- Burn rate: -$15.5k/month (investor funded)

Year 3: Profitability push
- Removed "redundant" base stations (5 decommissioned)
- Reduced costs: $6k/month maintenance
- Subscriber revenue grew: $5k/month
- Now break-even
- But: Coverage degraded 33%!

Key Insight:

Sigfox’s operator-dependent model means you have zero control over infrastructure: - Cannot add base stations yourself - No SLA guarantees (best-effort service) - No visibility into infrastructure changes until messages fail - Economic pressures on operator directly impact your deployment

Comparison: LoRaWAN Private Network - You deploy 8 gateways (8 x $500 = $4k) - Year 3 performance degrades? Deploy 2 more gateways ($1k) - You control: placement, upgrades, monitoring - No third-party dependency

Mitigation Strategy: - For mission-critical deployments: hybrid approach (Sigfox + 10 LoRaWAN gateways in critical zones = $5k) - Design sensors with modular radios (swap Sigfox to LoRaWAN if needed) - Monitor message success rate monthly (detect degradation early)

The Lesson: “Free” infrastructure (Sigfox model) isn’t free–you pay with control. For 10-year deployments, ownership may be worth 10x upfront cost.

1123.6 Sigfox vs LoRaWAN: Operational Control

Question: What is the MOST significant architectural difference between Sigfox and LoRaWAN that impacts operational control?

Option A is the fundamental architectural difference:

Sigfox Architecture (Operator-Only):

Devices -> Sigfox Base Stations -> Sigfox Backend -> Your Application
           ^                       ^
      Operator Owned          Operator Owned
      (You have NO control)   (Managed service)

Key characteristics: - Base stations: Deployed and operated by Sigfox Network Operator (SNO) - Network: Managed as a service (like cellular carriers) - Control: ZERO user control over infrastructure - Advantages: No CapEx, no deployment effort, no maintenance - Disadvantages: Coverage dependency, no optimization ability, operator risk

LoRaWAN Architecture (Private Network Option):

Devices -> Your Gateways -> Your Network Server -> Your Application
           ^                ^
      You Own & Control   You Own & Control

Key characteristics: - Gateways: User deploys private infrastructure - Network: User runs network server - Control: COMPLETE control over infrastructure - Advantages: Full control, optimization, no subscription fees, privacy - Disadvantages: CapEx required, deployment effort, maintenance burden

Why Other Options Are Less Fundamental: - B (Modulation): Technical performance difference, but doesn’t affect control/ownership - C (Data rate): Application suitability, but doesn’t affect control - D (Message limit): Protocol constraint, but doesn’t affect control

The infrastructure ownership model determines who owns and controls the network–the fundamental decision point for LPWAN technology selection.

1123.7 Operator Risk Scenarios

Scenario 1: Coverage gap discovered

Approach Sigfox LoRaWAN
Discovery 30% sensors have poor connectivity Same
Action Contact operator, request base station Purchase gateway ($1,500)
Response “Business case insufficient, denied” Install and configure
Result Accept loss OR switch technology 100% coverage achieved
Timeline Months (if agreed), never (if denied) 1-2 weeks

Scenario 2: Scaling from 100 to 10,000 devices

Aspect Sigfox LoRaWAN
Action Activate subscriptions Deploy additional gateways
Cost $59,400/year ongoing $15,000 one-time
Deployment Instant (if coverage) 1-2 months
Control None Full

Scenario 3: Operator bankruptcy (Sigfox SA 2022)

Aspect Sigfox LoRaWAN
Impact Service disruption possible Zero (private network)
User action Wait for resolution Continue operating
Risk Stranded assets None

1123.8 Mitigation Strategies

TipDesigning for Resilience

1. Hybrid Deployment ($5k for 10 gateways) - Sigfox primary coverage in operator-covered zones - LoRaWAN backup in critical zones - Unified application layer aggregates both

2. Monthly Monitoring - Track message success rates - Alert on degradation > 5% - Detect issues before critical impact

3. Modular Radio Design - Design devices with swappable radios - Migration path: Sigfox to LoRaWAN ready - Firmware supports multiple protocols

4. SLA Negotiation - Request guaranteed coverage SLAs - Rare, expensive, often refused - Document all commitments

1123.9 Total Cost of Ownership Analysis

10-Year Deployment Comparison (5,000 devices)

Cost Item Sigfox Private LoRaWAN
Device Hardware $25,000 $75,000
Subscriptions $3,000,000 $0
Gateway Infrastructure $0 $5,000
Backhaul Connectivity $0 $24,000
Total 10-Year $3,025,000 $104,000
Control Level Zero 100%
Coverage Risk High None

Key Insight: “Free” infrastructure (operator-managed model) costs you control. For mission-critical 10-year deployments, the higher upfront cost of private infrastructure may provide better long-term value through operational control and coverage stability.

1123.10 Summary

Sigfox’s operator-managed infrastructure model presents unique risks:

  • Zero control over base station deployment, coverage, or network quality
  • Coverage degradation can occur when operators optimize infrastructure for profitability
  • Economic pressures on operators directly impact your deployment quality
  • No SLA guarantees in most standard subscriptions
  • Operator bankruptcy risk demonstrated by Sigfox SA filing in 2022
  • Mitigation requires hybrid deployments, monthly monitoring, and modular device design
  • TCO analysis may favor private infrastructure for long-term, mission-critical deployments

1123.11 What’s Next

Continue your Sigfox learning: