GCRI · Critical Infrastructure
Telecommunications and cables
Telecommunications carry emergency calls, warnings, payments, business and government. Mobile and fixed networks depend on power, backhaul links, data centres and, between continents, a small number of submarine cables. This page sets out how communications fail, from local power loss to cable cuts, how resilience is measured, and what evidence serves the operators and regulators who keep networks running.
Telecommunications and cables on the record.
Telecommunications and cables: how the risk develops.
Communications, data links and shared dependencies. The dossier below sets out how the risk develops, what is measured, where the data come from, how it is modelled and who decides.
Base stations run on batteries
Mobile sites have batteries and sometimes generators for hours of backup. Widespread power outages longer than that take sites off air, often exactly when people need to call for help.
Cables concentrate in corridors
Submarine cables carry nearly all intercontinental data and land at a limited number of stations. Anchors, fishing, seabed movement and deliberate damage can cut several cables in one corridor.
Services concentrate in data centres
Applications and network functions are hosted in a few data centres and cloud regions. Their power, cooling and connectivity become shared dependencies for many services.
Repairs depend on ships and crews
Cable repair needs specialised ships, permits and calm weather. Limited repair capacity means outages can last weeks when several cables fail.
Asset criticality register.
The screen a team would use to follow this subject: its measures, states and decisions. Names are examples and values are illustrative.
Asset criticality register
Telecommunications and cables · Lifeline system A · Register v5
Critical assets
| SS-12 | Electricity | Tier 1 | Flood 1-in-100 | 22 |
| WTW-2 | Water | Tier 1 | Flood 1-in-100 | 42 |
| DX-1 | Telecom | Tier 2 | Heat | 11 |
| H-Campus | Health | Tier 1 | Earthquake | 52 |
| PN-3 | Transport | Tier 2 | Storm surge | n/a |
SS-12 dependencies
- Upstream
- Transmission L4, L7
- Downstream
- WTW-2, H-Campus, DX-1
- Restoration target
- 10 h
- Owner
- Asset owner
Dependency graph
red: SS-12 and its dependants
Restoration time by sector
Communications carry the control and coordination of every domain.
- EnergyCouplingGrid control depends on telecoms that depend on power.What to watchTelecom backup at grid sites
- HealthCouplingTelemedicine and records need connectivity.What to watchHealth services offline during outages
- WaterCouplingUtility telemetry and control use communications networks.What to watchTelemetry loss events
Telecommunications studies are designed for the Strategic Systems series. Submarine cable protection follows International Cable Protection Committee guidance, and ITU recommendations address network resilience to disasters.
- Cable fault and repair records.
- Network outage reports during disasters.
A cascade through interdependent networks.
A hazard footprint takes out co-located assets in every layer; fragmentation, dependency between layers and overload of the survivors then spread the failure. The 3D view separates the layers by depth. Teaching model with stated illustrative values, not a prediction.
Controls
- Assets per layer
- 18
- Hazard footprint
- 8% of area
- Assets that depend on another layer
- 60%
- Spare capacity (tolerance)
- 30%
Readouts
- Assets hit by the hazard
- 9%
- Assets still working
- 28%
- Amplification of the initial damage
- 7.8 times
- Steps to settle
- 4
Numbers, methods and sources
| Step | Transport working (%) | Power working (%) | Telecoms working (%) |
|---|---|---|---|
| 0 | 94 | 89 | 89 |
| 1 | 78 | 44 | 89 |
| 2 | 44 | 28 | 61 |
| 3 | 44 | 28 | 17 |
| 4 | 44 | 28 | 11 |
Methods
- Interdependent networks Buldyrev and others (2010), Catastrophic cascade of failures in interdependent networks, Nature 464
- Overload cascades Motter and Lai (2002), Physical Review E 66
- Betweenness load Brandes (2001), Journal of Mathematical Sociology 25
- Multilayer networks Kivela and others (2014), Journal of Complex Networks 2
- Infrastructure interdependencies Rinaldi, Peerenboom and Kelly (2001), IEEE Control Systems 21(6)
- Uncertainty fan (parameter Monte Carlo) Spiegelhalter, Pearson and Short (2011), Visualising uncertainty about the future, Science 333
- One-at-a-time sensitivity (tornado) Saltelli and others (2008), Global Sensitivity Analysis: The Primer, Wiley
Data
The model runs on the teaching values set by the controls. To calibrate it for a place, read it against these admitted layers and series, which this page's map can draw:
- Major roads Natural Earth
- Railways Natural Earth
- Seaports Natural Earth
- Airports Natural Earth
- Urban extents Natural Earth
- Night lights tonight, outages (VIIRS Day/Night Band) NASA/NOAA VIIRS (Suomi NPP) · register nasa.gibs.context-live-layers
- Natural events (NASA EONET) NASA EONET · register nasa.eonet.events
Across the six pillars, led by Nexus Consortium
- Experiments Labs
- Built in Critical Infrastructure in Foundry
- Tested at Critical Infrastructure in Universe
- Codified in Energy and Critical Infrastructure in Standards
- Published in Critical Infrastructure in Reports
- Taught in Faculty of Infrastructure, Energy and Industry in Academy
What is measured, and how well.
Each indicator carries its unit, its cadence, the kind of source behind it and the evidence label a value would carry. No values are shown: a programme supplies them under its own authority.
| Indicator | Unit | Cadence | Source type | Label |
|---|---|---|---|---|
| Mobile sites off air | percent of sites | hourly during events | Operator reports to regulators | REPORTED |
| Network outage incidents | count by cause | annual | Regulator incident reporting | Published statistics |
| Submarine cable landings per country | count of cable systems | annual | Cable databases | REPORTED |
| International bandwidth redundancy | count of independent routes | annual | Network route analysis | ESTIMATED |
| Base station backup duration | hours | per site class | Operator design standards | DECLARED |
| Cable repair time | days from fault to repair | per event | Operator and industry reports | REPORTED |
How telecommunications and cables is modelled, measured and tested.
The model, its assumptions, its data and its uncertainty, in the form a scientist or engineer would check. Structures follow published methods. The values drawn are illustrative, not findings.
System model
The couplings between the systems in telecommunications and cables: signs of influence, a reinforcing and a balancing loop, and cross-links where stress jumps.
Where the evidence comes from.
Named public datasets and institutional records, each with its licence class. Sources by agreement are used only under their terms and never republished.
| Source | What it gives | Licence class |
|---|---|---|
| ENISA annual telecom security incident reports | Aggregated incident reports from EU member states by cause and impact | Public, ENISA terms |
| US FCC Network Outage Reporting System summaries and Disaster Information Reporting System | Outage reporting and cell site status during disasters | Public summaries, US government |
| TeleGeography Submarine Cable Map | Submarine cable systems and landing stations | Licence to check (CC BY-NC-SA for the map data) |
| ITU World Telecommunication/ICT Indicators | Network coverage and connectivity statistics by country | Free for some tables, ITU terms (to check) |
| International Cable Protection Committee recommendations | Industry recommendations on cable protection and repair | Members; public summaries |
Who decides, and what the evidence serves.
Critical Infrastructure prepares evidence. The decisions below are taken by the authorities named, under their own rules, and never by the platform.
| Who decides | The question | Evidence this page serves |
|---|---|---|
| Telecommunications regulators | What resilience and backup obligations to set for operators | Outage data; backup reviews |
| Network operators | Where to add route diversity and backup power | Route analyses; incident patterns |
| Governments and port authorities | How to protect cable landings and corridors | Cable concentration and repair evidence |
Outputs this topic produces
- Route diversity analyses of international connectivity
- Power backup reviews for mobile networks in outages
- Concentration analyses of data centre and cloud dependencies
- Evidence notes on cable repair capacity and timelines
What experts ask.
- Which essential services lose function when communications fail, and how quickly?
- Where do apparently diverse routes actually share ducts, landing stations or data centres?
- How long do mobile sites and exchanges operate on backup power?
- How exposed are submarine cables and their landing points, and how fast can they be repaired?
- What role can satellite links play as backup, and with what capacity limits?
Drivers and failure pathways.
Communications networks are designed with redundancy, but diversity on paper is not always diversity in the ground. Separate operators may lease capacity on the same fibre, routes may converge on one bridge or landing station, and many services depend on a small number of data centres and internet exchange points. When those shared points fail, apparently independent services fail together.
Power is the dominant dependency. Mobile base stations and street cabinets typically hold limited battery backup, so extended power outages lead to progressive loss of coverage, just when people need to call for help. Submarine cables carry most intercontinental data traffic; faults from anchors, fishing, seabed movement and deliberate damage are repaired by a small fleet of specialised ships, so repair times can be long.
Cyber intrusion is a further pathway, studied with Cybersecurity and Digital Resilience.
How it is studied.
- 01
Network topology analysis
Graph methods from network science and contagion identify chokepoints and shared routes.
- 02
Route diversity audits
Physical route records show whether redundant links truly follow separate paths.
- 03
Backup and satellite assessment
Engineering analysis from communications and network technology and space systems and satellite services assesses backup duration and alternative links.
- 04
Limits
Route and capacity data is commercially sensitive and often unavailable. Public maps of cables and exchanges are incomplete, and network behaviour under heavy emergency load is hard to test.
How it is studied, and what the methods cannot say.
- 01Communications and network technologyMission-critical communications · Backhaul diversity · Communication dependencies of operatorsApplied here
- 02Network science and contagionCritical node and link analysis · Interdependent network models · Redundancy assessmentApplied here
- 03Reliability and resilience engineeringResilience metrics for lifelines · Reliability analysis of networks · Restoration planningApplied here
- 04Space systems and satellite servicesTiming dependency review · Satellite backup communications · Asset monitoring from spaceApplied here
- 05Energy generation, storage and grid technologyBackup power options · Microgrids for critical services · Fuel supply in emergenciesApplied here
Where this page's references lead.
The bodies and documents this page is read against. Status and editions change; each link goes to the issuing body.
Questions and answers.
How much data travels by submarine cable?
How long can mobile networks run without power?
What is route diversity?
Are two different providers enough for resilience?
Can satellites replace terrestrial networks in a crisis?
Does the platform publish cable vulnerabilities?
Who reviews coverage of this topic?
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