Subsea Cables
9 submarine cables connecting the Isle of Man to the UK, Ireland, and beyond — from the first telegraph cable in 1859 to 2022's 300 Tbps fibre system.
AI Subsea Fibre Analysis
Infrastructure advisory generated by Azure OpenAI - click to expand22 Mar 2026
AI Subsea Fibre Analysis
Infrastructure advisory generated by Azure OpenAI - click to expand22 Mar 2026
Isle of Man Submarine Fibre Infrastructure: Advisory Report
Date: 22 March 2026
Prepared by: Telecoms Infrastructure Analyst – Subsea Networks & Island Connectivity
Current Infrastructure Assessment
Submarine Cable Inventory
| Cable Name | Year | Landing Points | Design Capacity | Status |
|---|---|---|---|---|
| 1859 Telegraph | 1859 | Douglas | N/A (historic) | Decommissioned |
| Isle of Man - England | 1988 | Douglas - Blackpool | 2.5 Gbps (upgraded to 10 Gbps) | Active (limited) |
| Isle of Man - Scotland | 1992 | Douglas - Portpatrick | 10 Gbps | Active (limited) |
| LANIS 1 | 2000 | Douglas - Blackpool | 40 Gbps | Active |
| LANIS 2 | 2000 | Douglas - Liverpool | 40 Gbps | Active |
| BT Gemini | 2001 | Douglas - Southport | 10 Gbps | Active |
| e-llan (Interconnector) | 2011 | Douglas - Blackpool | 1 Tbps (potential) | Active (operator ceased 2024) |
| CeltixConnect-2 / Havhingsten | 2022 | Douglas - Dublin - Blackpool | 300 Tbps | Active |
Total Lit and Dark Fibre Capacity
- Lit capacity: Estimated at 2-5 Tbps (2026), primarily on CeltixConnect-2/Havhingsten; older systems operate at lower rates, often as backup or for legacy traffic.
- Dark fibre: Substantial on CeltixConnect-2/Havhingsten, but limited market take-up due to high costs and limited local demand. e-llan’s dark fibre is now in limbo.
Redundancy & Single Points of Failure
- Multiple routes: At least three physically diverse landing points (Douglas, Port Erin, Port Grenaugh).
- Redundancy: Theoretically high, but practical redundancy depends on who owns/operates each cable. Several cables are owned by the same operator (Manx Telecom/BT), reducing true diversity.
- Single points of failure: Most cables land within a 5 km stretch near Douglas, creating a geographic vulnerability. Shared ducts and beach manholes further increase risk.
- International dependence: Most routes go to the UK; only CeltixConnect-2/Havhingsten provides direct Ireland (EU) connectivity.
Demand Forecast
Key Demand Drivers (2026–2040)
- AI workloads: Training typically off-island, but inference (real-time AI services) will require low-latency, high-capacity links. Growth rate: 30–50% CAGR.
- Cloud computing: Increased adoption by public sector, finance, and gaming. Multi-cloud, hybrid environments will demand resilient, high-capacity links.
- Remote work & streaming: Pandemic-era shifts are permanent. Peak traffic surges (events, esports, software updates) can saturate older links.
- IoT growth: Smart metering, e-health, and logistics will drive steady, but not overwhelming, traffic increases.
- Data sovereignty: Regulatory pressure (esp. for finance/gaming) to keep data flows within the IoM or EU, not just UK.
| Year | Peak Demand Estimate | Available Lit Capacity | Headroom |
|---|---|---|---|
| 2026 | 1.2 Tbps | 5 Tbps | 4.2x |
| 2030 | 3.5 Tbps | 10 Tbps (with upgrades) | 2.9x |
| 2040 | 18 Tbps | 50 Tbps (if all pairs lit) | 2.8x |
Conclusion: CeltixConnect-2/Havhingsten provides significant future-proofing, but only if its capacity is fully accessible and affordable. Legacy cables are not fit for 2040 demands. True future-proofing requires both capacity and diversity (multiple owners, routes, landing points).
The e-llan Question
e-llan Cessation: Impacts
- Market effect: Loss of the only independent dark fibre wholesaler. Remaining cables are vertically integrated (owned by incumbent telcos).
- Competition: Reduced. Risk of oligopoly pricing for backhaul and transit. New entrants (ISPs, datacentre operators) face higher barriers.
- Pricing: Likely to rise for wholesale capacity. Retail broadband may stagnate in speed/price improvements.
- Strategic risk: Loss of a neutral operator weakens the island’s negotiating position with UK/EU carriers.
Should Government Intervene?
Yes. The IoM government should treat international fibre as strategic infrastructure. Options:
- Appoint a special administrator to maintain e-llan’s assets and keep dark fibre available to the market.
- Facilitate a new neutral wholesale operator (public-private partnership or trust model).
- Mandate open-access conditions on all new and existing cables landing in the IoM.
Starlink & LEO Satellite
Viability for the Isle of Man
- Price/Performance: £35/month for 100 Mbps down; 20–40 Mbps up. Latency: 40–70 ms (best case).
- Resilience: Excellent backup for disaster recovery or rural/remote sites.
- Financial services & gaming: Not suitable. Latency is too high and jitter too variable for high-frequency trading, e-gaming, or regulated financial apps.
- Enterprise/Datacentre: Not a substitute for fibre; insufficient guaranteed throughput, no SLA, and security concerns.
- Residential/SME: Good supplement, especially in underserved areas, but not a replacement for fibre.
Conclusion: Starlink and LEO are complementary, not competitive, to fibre for the IoM’s strategic needs.
Internet Exchange Point
ManxIX: Is a Local IXP Justified?
- Current status: Exists, but no active local peers. All major ISPs peer in London/Dublin/Manchester.
- Economics: For 84,000 people, local traffic is minimal. Running a full IXP is hard to justify unless more datacentres or content providers (CDNs) establish a presence.
- Data sovereignty: A local IXP would keep intra-island traffic on-island, improving privacy and resilience, but only if ISPs and government agencies participate.
- Latency: Marginal improvement for local services, but most content (Netflix, AWS, gaming) is hosted off-island anyway.
- Resilience: A local IXP is useful for emergency communications, but not critical for everyday use.
Conclusion: London/Dublin peering is sufficient for now. A local IXP should be kept “warm” for emergency use or if IoM attracts more datacentres/CDNs.
BGP & Autonomous Systems
ASNs in the Isle of Man
- Country code: IM (Isle of Man has its own ccTLD and is a RIPE NCC member).
- ASN allocation: A handful of local ASNs (e.g., Manx Telecom, Sure, Wi-Manx) originate from the IoM, but most traffic is announced and routed via UK parent ASNs.
- Routing implications: Most IoM traffic transits through UK carriers, subjecting it to UK jurisdiction and surveillance. This undermines true internet sovereignty and can create legal/regulatory ambiguity for finance and gaming.
- Resilience: If the UK suffers a major outage or routing incident, IoM traffic is affected.
Recommendation: Encourage more local ASN origination and direct peering to Ireland/EU, not just the UK, to increase sovereignty and resilience.
Recommendations
For Isle of Man Government and Regulators
- 1. Strategic Fibre Policy
- Declare international fibre as critical national infrastructure.
- Reform landing licence regime: require open access and route diversity for all new cables.
- 2. e-llan Successor
- Facilitate the creation of a neutral, regulated wholesale dark fibre operator.
- Consider public investment or a trust model if no private buyer emerges.
- 3. Redundancy & Diversity
- Incentivise at least one new cable with a physically diverse landing point (not Douglas).
- Mandate route separation in ducting and landing stations.
- 4. ASN & Routing Sovereignty
- Encourage ISPs and enterprises to originate their own ASNs and peer directly with Ireland/EU.
- Support BGP training and tools for local network operators.
- 5. IXP & Local Traffic
- Maintain ManxIX as a “warm standby” for resilience, but do not subsidise full-scale IXP operations unless datacentre demand rises.
- 6. Satellite as Supplement
- Encourage Starlink and LEO as rural or backup solutions, but do not treat as strategic replacements for fibre.
- 7. Regulatory Oversight
- Monitor wholesale pricing and competition post-e-llan. Intervene if market power is abused.
- Set clear service levels for cable maintenance, repair, and upgrade cycles.
Summary Table: Priority Actions
| Action | Timeline | Lead Agency |
|---|---|---|
| Appoint e-llan administrator / successor | Immediate | Dept. for Enterprise / Communications Commission |
| Open-access regime for new cables | 2026–2027 | Communications Commission |
| Route diversity incentives | 2026–2028 | Dept. for Enterprise |
| Promote local ASN origination | 2026–2029 | ISPs / Regulator |
| Maintain ManxIX as standby | Ongoing | ManxIX / Regulator |
Final Opinion
The Isle of Man’s submarine fibre network is robust but not invulnerable. The collapse of e-llan is a wake-up call: without intervention, the island risks higher prices, less innovation, and increased strategic risk. Government action is essential to secure the island’s digital future and maintain its competitive edge in finance, gaming, and e-business.
Cable Timeline
Cranstal-St Bees Telegraph Cable
HistoricTelegraphThe first ever submarine cable connecting the Isle of Man. Commissioned from Glass, Elliot and Company of Greenwich and laid by the chartered cable ship Resolute in August 1859. Connected the island to the UK telegraph network for the first time, allowing messages to be sent to the mainland. The telegraph cables remained in place but fell out of use by the 1950s.
Dalton-Douglas Microwave Link
DecommissionedMicrowave RadioAfter the telegraph cables fell silent in the 1950s, the island relied on microwave radio links for its trunk telecommunications. Planned in the late 1960s and operational by the early 1970s, the Dalton relay station near Barrow-in-Furness beamed 300 telephone circuits to Douglas at 11 GHz — one of the first links to operate in that band. In the 1980s, a new digital microwave route via Northern Ireland was added. These microwave links were the island's primary connection to the outside world until fibre optic cables replaced them in 1988. The Dalton tower retained dishes aimed at Douglas until at least 2004.
Port Grenaugh-Silecroft Fibre
ActiveFibre OpticInaugurated on 28 March 1988, this was the longest unregenerated fibre optic system in Europe at the time. The cable was laid in September 1987 and buried along its entire length in the seabed. A landmark moment for Manx connectivity.
BT-MT1
ActiveFibre OpticLaid in October 1990, jointly operated by BT and Manx Telecom. Originally six channels at 140 Mbit/s each, but like most modern fibre cables, capacity has been significantly upgraded using WDM (Wavelength Division Multiplexing) and DWDM technology — multiplexing many wavelengths of light onto a single fibre pair. This cable remains in use today.
LANIS-1
ActiveFibre OpticLaid by Mercury Communications in July 1992. Part of the LANIS (Local Access Network Interconnection System) pair. Originally six channels at 565 Mbit/s each, now significantly upgraded via WDM/DWDM multiplexing. Operated by Cable & Wireless, providing diverse routing from the BT-MT1 cable.
LANIS-2
ActiveFibre OpticThe companion to LANIS-1, also laid by Mercury Communications in July 1992. Provides the island's only direct fibre link to Ireland/Northern Ireland outside of the newer CC-2 system. Operated by Cable & Wireless.
IoM-England Interconnector
ActivePower + FibreInstalled in September 2000 and the longest AC subsea power cable in the world at the time. Bundles a 132kV power cable with a fibre optic communications cable. The electricity cable connects the Manx grid to the UK National Grid. The fibre was operated by e-llan Communications (a Manx Utilities subsidiary), providing wholesale bandwidth — the fibre was lit in December 2007. E-llan ceased trading on 31 December 2024, citing declining customer demand and operating losses of ~£128k. The power cable remains critical infrastructure; the fibre's future use is unclear.
CeltixConnect-1 (CC-1)
ActiveFibre OpticA 72-fibre pair subsea cable connecting Ireland and the UK. While CC-1 does not land on the Isle of Man directly, the CC-2 extension (2022) connects to this cable, forming a fully diverse circuit between Dublin and Blackpool with IoM branches. Part of the Aqua Comms AEConnect transatlantic network.
CeltixConnect-2 / Havhingsten (CC-2)
ActiveFibre OpticThe newest and most significant cable for the island. Part of the Havhingsten system jointly owned by Aqua Comms, Bulk Fiber Networks and Meta. The world's first aluminium conductor powered subsea cable. Two branches land on the Isle of Man at Port Erin and Port Grenaugh, with 75 km of cable buried in Manx seabed. 555,000 scallops were relocated from a 7.5 km stretch of seabed during installation. CC-2 capacity is presented in a local data centre, though public details on uptake are limited. Ready for service March 2022, designed to last until 2047.
Isle of Man Landing Points
A Note on Capacity: WDM & DWDM
The original capacity figures above reflect what each cable was designed for at installation. In practice, modern fibre cables carry vastly more data than their original specifications suggest, thanks to Wavelength Division Multiplexing (WDM) and its denser variant DWDM. These technologies multiplex dozens or hundreds of independent light wavelengths onto each fibre pair, effectively turning a single fibre strand into many parallel channels. A cable originally rated at 565 Mbit/s per channel in 1992 can carry orders of magnitude more traffic today with modern DWDM transponders.
Connectivity Context: Peering & Internet Exchange
Despite seven active submarine cables, the Isle of Man has no neutral peering point with active local participants. MINX (Manx Internet Exchange) was established as the island's first IXP but did not gain traction. ManxIX, formed in 2020 and hosted in BlueWave's carrier-neutral facility in Douglas with LINX as technical partner, is the current exchange — but as of 2025 has no active IoM peers on its network.
This means all inter-provider traffic between IoM networks still transits via the UK mainland, adding latency and cost. A functioning local IXP would keep local traffic local — reducing round-trip times from up to 30ms between on-island networks to sub-millisecond, and lowering transit costs for every operator.
Latency: IoM to Manchester ~2ms, IoM to London ~8ms. Inter-network on-island: 1-30ms depending on path.
About This Data
Cable information compiled from public sources including Wikipedia, ISPreview, Submarine Cable Map, IoM Government press releases, and CURA regulatory documents. The IoM Government's National Telecoms Strategy (2018) identified subsea cable resilience as a critical strategic priority, leading to the CC-2/Havhingsten project.
Submarine cables in Manx waters are governed by the Submarine Cables Act 2003 (an Act of Tynwald).
Sources: Wikipedia | Submarine Cable Map | ISPreview | DfE IoM