RETN has launched a new fiber-optic cable connecting Cēsis, Latvia, with Tallinn, Estonia.

The line has a capacity of up to 40Tbps (terabits per second), along with a DWDM (Dense Wavelength Division Multiplexing) spectrum designed to support traffic rerouting and future increases in load.

Technically, the Tallinn-Cēsis line has already been operational once before, when engineers brought the cable online last year during its testing phase after the primary line connecting Estonia with Finland was cut by foresters. The new cable should boost regional resiliency, said RETN’s CEO, Tony O’Sullivan.

DCD has approached the firm for comment.

“Modern backbone networks have to be engineered on the assumption that outages are inevitable, therefore, the network design should be resilient from the start,” said O’Sullivan. “The Tallinn-Cēsis route was built as part of a deliberate resilience strategy – adding diversity at both the route and supplier level – so that when a failure occurs, traffic can be shifted quickly without compromising performance.”

The Tallinn-Cēsis line will also be serviced by a new Core PoP (Point of Presence) in Tallinn’s Greenergy data center. The cable performed well during its unscheduled alpha test, said RETN, with more than 40 DWDM backbone channels successfully diverted onto the line in under an hour.

This significantly exceeded normal traffic restoration timescales, the firm continued, when the usual absence of a backup line mandates the days-long restoration of the primary cable. “Despite the scale and complexity of the operation, key performance indicators, including latency and jitter, were maintained throughout,” said the company.

Founded in 2003, RETN initially concentrated on laying internet cables in the Baltic Sea region, Eastern Europe, Central Asia, and Russia. It has now limited its exposure to the latter market to comply with sanctions imposed on Russia after its invasion of Ukraine in 2022.

The UK-headquartered firm has since expanded its presence in Western Europe and Asia, launching new cables running between Marseille and Milan, London and Paris, and Singapore and Hong Kong.

Learn more about the data center market in Poland and Eastern Europe, and meet with other executives and experts from the region at the DCN Warsaw event later this year.