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Chokepoint

Critical Undersea Cable Hub at Tong Fuk: Challenges and Global Connectivity

📈 Live RTT from our measurements · last 30 days
Daily average per cable, in ms; red dots mark days with detected anomalies.
010020030040026.0702.0809.0816.0823.08Asia-America Gateway (AAG) Cable System · 26.07 · 233 msAsia-America Gateway (AAG) Cable System · 27.07 · 192 msAsia-America Gateway (AAG) Cable System · 28.07 · 199 msAsia-America Gateway (AAG) Cable System · 29.07 · 196 msAsia-America Gateway (AAG) Cable System · 30.07 · 205 msAsia-America Gateway (AAG) Cable System · 31.07 · 370 msAsia-America Gateway (AAG) Cable System · 01.08 · 234 msAsia-America Gateway (AAG) Cable System · 02.08 · 232 msAsia-America Gateway (AAG) Cable System · 04.08 · 240 msAsia-America Gateway (AAG) Cable System · 05.08 · 195 msAsia-America Gateway (AAG) Cable System · 06.08 · 197 msAsia-America Gateway (AAG) Cable System · 07.08 · 175 msAsia-America Gateway (AAG) Cable System · 08.08 · 222 msAsia-America Gateway (AAG) Cable System · 09.08 · 222 msAsia-America Gateway (AAG) Cable System · 10.08 · 222 msAsia-America Gateway (AAG) Cable System · 11.08 · 223 msAsia-America Gateway (AAG) Cable System · 12.08 · 222 msAsia-America Gateway (AAG) Cable System · 13.08 · 223 msAsia-America Gateway (AAG) Cable System · 14.08 · 223 msAsia-America Gateway (AAG) Cable System · 15.08 · 222 msAsia-America Gateway (AAG) Cable System · 16.08 · 222 msAsia-America Gateway (AAG) Cable System · 18.08 · 221 msAsia-America Gateway (AAG) Cable System · 19.08 · 224 msAsia-America Gateway (AAG) Cable System · 20.08 · 206 msAsia-America Gateway (AAG) Cable System · 21.08 · 200 msAsia-America Gateway (AAG) Cable System · 23.08 · 227 msSoutheast Asia-Japan Cable (SJC) · 26.07 · 82 msSoutheast Asia-Japan Cable (SJC) · 27.07 · 164 msSoutheast Asia-Japan Cable (SJC) · 28.07 · 195 msSoutheast Asia-Japan Cable (SJC) · 29.07 · 192 msSoutheast Asia-Japan Cable (SJC) · 30.07 · 153 msSoutheast Asia-Japan Cable (SJC) · 31.07 · 82 msSoutheast Asia-Japan Cable (SJC) · 01.08 · 82 msSoutheast Asia-Japan Cable (SJC) · 02.08 · 82 msSoutheast Asia-Japan Cable (SJC) · 03.08 · 80 msSoutheast Asia-Japan Cable (SJC) · 04.08 · 82 msSoutheast Asia-Japan Cable (SJC) · 05.08 · 182 msSoutheast Asia-Japan Cable (SJC) · 06.08 · 82 msSoutheast Asia-Japan Cable (SJC) · 07.08 · 82 msSoutheast Asia-Japan Cable (SJC) · 08.08 · 82 msSoutheast Asia-Japan Cable (SJC) · 09.08 · 89 msSoutheast Asia-Japan Cable (SJC) · 10.08 · 85 msSoutheast Asia-Japan Cable (SJC) · 11.08 · 81 msSoutheast Asia-Japan Cable (SJC) · 12.08 · 88 msSoutheast Asia-Japan Cable (SJC) · 13.08 · 85 msSoutheast Asia-Japan Cable (SJC) · 14.08 · 82 msSoutheast Asia-Japan Cable (SJC) · 15.08 · 149 msSoutheast Asia-Japan Cable (SJC) · 16.08 · 124 msSoutheast Asia-Japan Cable (SJC) · 17.08 · 77 msSoutheast Asia-Japan Cable (SJC) · 18.08 · 82 msSoutheast Asia-Japan Cable (SJC) · 19.08 · 83 msSoutheast Asia-Japan Cable (SJC) · 20.08 · 88 msSoutheast Asia-Japan Cable (SJC) · 21.08 · 82 msSoutheast Asia-Japan Cable (SJC) · 22.08 · 89 msSoutheast Asia-Japan Cable (SJC) · 23.08 · 85 msAsia Africa Europe-1 (AAE-1) · 28.07 · 210 msAsia Africa Europe-1 (AAE-1) · 29.07 · 210 msAsia Africa Europe-1 (AAE-1) · 31.07 · 215 msAsia Africa Europe-1 (AAE-1) · 01.08 · 209 msAsia Africa Europe-1 (AAE-1) · 02.08 · 214 msAsia Africa Europe-1 (AAE-1) · 03.08 · 225 msAsia Africa Europe-1 (AAE-1) · 07.08 · 211 msAsia Africa Europe-1 (AAE-1) · 08.08 · 221 msAsia Africa Europe-1 (AAE-1) · 09.08 · 222 msAsia Africa Europe-1 (AAE-1) · 10.08 · 232 msAsia Africa Europe-1 (AAE-1) · 11.08 · 212 msAsia Africa Europe-1 (AAE-1) · 12.08 · 233 msAsia Africa Europe-1 (AAE-1) · 13.08 · 339 msAsia Africa Europe-1 (AAE-1) · 14.08 · 223 msAsia Africa Europe-1 (AAE-1) · 17.08 · 206 msAsia Africa Europe-1 (AAE-1) · 18.08 · 206 msAsia Africa Europe-1 (AAE-1) · 19.08 · 216 msAsia Africa Europe-1 (AAE-1) · 20.08 · 212 msAsia Africa Europe-1 (AAE-1) · 21.08 · 210 msEAC-C2C · 28.07 · 207 msEAC-C2C · 29.07 · 214 msEAC-C2C · 30.07 · 67 msEAC-C2C · 31.07 · 91 msEAC-C2C · 01.08 · 90 msEAC-C2C · 02.08 · 91 msEAC-C2C · 03.08 · 92 msEAC-C2C · 04.08 · 89 msEAC-C2C · 05.08 · 193 msEAC-C2C · 06.08 · 99 msEAC-C2C · 07.08 · 98 msEAC-C2C · 08.08 · 94 msEAC-C2C · 09.08 · 89 msEAC-C2C · 10.08 · 97 msEAC-C2C · 11.08 · 98 msEAC-C2C · 12.08 · 99 msEAC-C2C · 13.08 · 94 msEAC-C2C · 14.08 · 97 msEAC-C2C · 15.08 · 189 msEAC-C2C · 16.08 · 111 msEAC-C2C · 17.08 · 203 msEAC-C2C · 18.08 · 99 msEAC-C2C · 19.08 · 106 msEAC-C2C · 20.08 · 199 msEAC-C2C · 21.08 · 98 msEAC-C2C · 22.08 · 94 msEAC-C2C · 23.08 · 95 ms

Geometry of the Location: Depths, Shores, Shipping

The chokepoint at Tong Fuk, located on the southwestern tip of Lantau Island in Hong Kong (latitude 22.0000, longitude 114.0000), is a narrow corridor where submarine cables cross on their way between East and Southeast Asia, as well as more distant regions. Hong Kong's geographic position makes it a natural hub for connecting networks from China, Japan, Korea, Taiwan and the Philippines to trunk lines leading to the Middle East, Europe and the USA.

The depths of the South China Sea and proximity to densely populated shores limit options for alternative routes. Additionally, the straits and shallow waters around Hong Kong are heavily utilized for shipping, adding complexity to cable laying. All these factors compel operators to concentrate their systems in one narrow corridor, minimizing construction and operational costs.

What's Packed In: 17 Cables and Their Trunk Lines

The chokepoint at Tong Fuk is traversed by 17 submarine cables, including some of the longest and most critical trunk lines in the world. Among them:

  • EAC-C2C (36,500 km): The world's largest submarine network, connecting key cities in Asia.
  • FLAG Europe-Asia (FEA) (28,000 km): A trunk line linking Europe to Asia via the Middle East.
  • Asia Africa Europe-1 (AAE-1) (25,000 km): Connects Asia, the Middle East and Europe.
  • Asia-America Gateway (AAG) (20,000 km): A key route between Asia and the USA.
  • APCN-2 (19,000 km): A regional network covering East and Southeast Asia.

These cables provide connectivity between countries such as China, Japan, the Philippines, Egypt, Singapore, Malaysia, Taiwan, Thailand, South Korea, Vietnam, Brunei, the USA, Jordan and Greece. Any disruption at this chokepoint could impact billions of users worldwide.

Alternative Corridors: Why They Don't Solve the Problem

While it is theoretically possible to lay cables bypassing Tong Fuk, this comes with significant challenges. The South China Sea has a complex seabed topography, including deep trenches and underwater mountains, which increases the cost of laying cables. For instance, extending the route to bypass Hong Kong could add thousands of kilometers to the cable length, raising construction and operational costs and introducing additional delays in data transmission.

Moreover, alternative routes, such as straits south of Taiwan or through the Philippines, are themselves vulnerable to natural disasters, including earthquakes and typhoons that frequently occur in the region. This makes Tong Fuk an almost irreplaceable node for submarine cable infrastructure.

Breakdown Scenario: Step by Step

In the event of a break in one or more cables near Tong Fuk, the consequences would be felt almost immediately. Here's how the situation might unfold:

  • First Minutes: Traffic passing through the damaged cables is automatically rerouted to backup routes, if available. However, due to the high concentration of cables at this chokepoint, overload on backup routes is inevitable.
  • First Hours: Data transmission delays (RTT) increase, especially for routes between Asia and Europe or the USA. Users may notice slower internet speeds, particularly when accessing international resources.
  • First Days: Cable system operators begin assessing the damage and planning repair work. Depending on the extent of the damage and weather conditions, repairs could take anywhere from several days to weeks.

Although such events are rare, they highlight the importance of monitoring and having backup capacities to minimize the impact.

What GeoCables Monitors

GeoCables closely monitors the condition of submarine cables in the Tong Fuk area. Currently, one RTT delay anomaly has been recorded at this chokepoint over the past 30 days, indicating high operational stability. We also track vessel movements near the cables to minimize the risk of damage from anchors or trawls.

Additionally, our analytics enable the assessment of potential impacts from cable breaks and the development of scenarios for rapid response. This is especially crucial for zones like Tong Fuk, where geography dictates routes, leaving operators with minimal room for maneuver.

🗺 The zone on the live map
Open the full map →
⚓ Cables in this zone: live status
From our monitoring network; baseline is the cable's normal RTT.
CableLengthRFSRTT nowBaselineStatus
Asia Africa Europe-1 (AAE-1)25,000 km2017--nominal
EAC-C2C36,500 km200295 ms-nominal
Asia-America Gateway (AAG) Cable System20,000 km2009231 ms-nominal
Southeast Asia-Japan Cable (SJC)8,900 km201389 ms89 msnominal
Asia Pacific Gateway (APG)10,400 km201689 ms89 msnominal
Asia Submarine-cable Express (ASE)/Cahaya Malaysia8,148 km201286 ms102 msnominal
Southeast Asia-Japan Cable 2 (SJC2)10,500 km202574 ms-nominal
Sihanoukville-Hong Kong (SHV-HK)2,938 km202641 ms-nominal
Evgeny K.
Written by
Evgeny K.
Infrastructure Engineer · Founder of GeoCables
Built GeoCables to monitor submarine cables in real time. Runs his own distributed network of measurement servers, including in regions poorly covered by public internet measurements.

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