Sparkle, Hellas Sat Test Quantum-Safe Link Between Greece and Cyprus

Sparkle and Hellas Sat have successfully established a quantum-safe data connection over a satellite link between Athens and Cyprus, the companies announced on September 2. This protection is provided by Sparkle’s Quantum Safe Interconnect (QSI), a software layer that rotates encryption keys. Unlike quantum devices, QSI operates without specialized hardware at either end. This trial marks a first for a Greece-Cyprus satellite link and is not yet a commercial service.

Details of the Experiment

Sparkle’s data center in Metamorfosi, Athens, was connected to Hellas Sat’s infrastructure in Cyprus. Data traversed approximately 72,000 kilometers, including the uplink from Cyprus to the satellite and the subsequent downlink to Greece. Previously, the companies had tested a secure IPsec connection between two data centers within Greece. This latest endeavor extends that setup to a live satellite hop between the two countries.

QSI employs a classical technique to keep traffic encrypted and automatically rotate keys on a set schedule. This limits the amount of data a single compromised key could expose. As QSI is software-based, it integrates with existing network equipment without requiring hardware changes. The companies position QSI as a solution to the “harvest-now-decrypt-later threat” problem, where attackers record encrypted traffic today, anticipating future machines capable of decrypting it. No such machines currently exist.

It’s important to clarify that “quantum-safe” in this context refers to frequent key rotation. The announcement does not indicate that QSI utilizes NIST-standardized post-quantum algorithms such as FIPS 203, 204, or 205, nor does it involve quantum key distribution. The term specifically describes a classical method, and the companies have not disclosed the specific cipher or rotation interval used.

Participants and Future Prospects

Hellas Sat operates three geostationary satellites and holds licenses from both Greek and Cypriot governments for the 39-degree-east orbital slot. Sparkle Greece operates four data centers and, according to the Cyprus Mail, holds a 40% share of the Greek cloud and data center market.

Constantinos Kassianides, Hellas Sat’s Director of Ground Operations, outlined the next steps:

“By combining our satellite infrastructure with Sparkle’s QSI solution, we are able to explore the commercial availability of quantum-secure satellite services for businesses operating in difficult-to-access, remote and critical locations.”

“Explore” tells us a lot here. There’s currently no product, no customers, no pricing, and no third-party validation of the security claims. What the two companies demonstrated is that their existing key-rotation software functions effectively over a satellite path, similar to how it performs over fiber. This represents a viable engineering outcome, though it neither involves nor defeats a quantum computer.