• ESA selected neXat to lead the €1.5m CableShield project with Telesat and Colt Technology Services Belgium
  • The 18-month programme will test automatic detection of subsea-cable failures and rerouting of selected traffic through pooled satellite capacity

The fact

The European Space Agency has selected neXat to lead CableShield, a €1.5m project with Telesat and Colt Technology Services Belgium to test automatic satellite backup when submarine fibre networks fail.

The 18-month programme will connect failure detection with terrestrial and satellite network controls so selected traffic can be rerouted without manual intervention. CableShield will use ESA's pooling-and-sharing interfaces to request capacity across multiple satellite providers rather than rely on one fixed backup network.

The system will also apply routing and traffic priorities because satellite capacity cannot reproduce the full throughput of a major submarine cable. The current award covers development and field validation rather than an operational service. neXat is targeting commercial availability in 2028, alongside the planned entry into service of Telesat Lightspeed.

The assessment

CableShield is designed for the period after a cable failure but before the damaged route is repaired. Satellite connectivity can provide another path, but the limited capacity means operators have to decide in advance which services should keep running and which can remain degraded.

Automation could shorten that handover if backup capacity is already available. The controller would need to detect the failure, obtain suitable satellite resources and move the selected traffic without creating congestion or unstable routing. That makes the field trial more than a demonstration that traffic can pass over satellite.

For BTW readers, CableShield will be useful if operators can preserve defined priority services quickly and predictably during a real fibre outage. Detection time, available satellite capacity and the amount of traffic carried will show whether the system can become a practical continuity layer rather than simply another backup option.

What to watch

Watch the field demonstration for measured failure-detection and switching times, the amount of traffic moved and whether priority rules hold under constrained capacity. Details of how satellite capacity is reserved or requested will also matter, because automatic routing offers less protection if bandwidth still has to be negotiated after the cable fails.