In a brief statement to The Associated Press, Telefonica SA acknowledged that it provides service to Cuba's state-run phone company, ETECSA, but disavowed any connection to the ALBA-1 cable, which was completed in February 2011.
"Telefonica has no involvement with the submarine cable ALBA-1, which links Cuba with Venezuela," chief press officer Miguel Angel Garzon said in the statement.
Telefonica was responding to a report by Internet intelligence firm Renesys, which noted faster data traffic to the island via Telefonica beginning last week, and concluded that it meant Cuba was finally using the fiber-optic cable.
Internet speed is calculated by measuring the fractions of seconds it takes to send a packet of data somewhere and then receive confirmation back at the original location.
The report's author, Renesys senior analyst Doug Madory, explained that it typically takes around 240 milliseconds for data to travel from earth to a satellite, so for satellite connections, so-called latency measurements are at least 480 milliseconds.
Last week he began detecting speeds below 480 and concluded that Cuba was apparently using the fiber-optic cable to handle incoming traffic, though outgoing data was being transmitted by satellite.
Madory told The Associated Press on Tuesday that speeds in Cuba had improved even further that morning, with "ping" tests conducted from Chicago and Los Angeles coming in at 180 and 200 milliseconds, respectively. That would mean no leg of the traffic was happening via satellite.
"It's almost getting to be a reasonable connection," Madory said.
He said the Telefonica statement was not in conflict with his report. The cable was strung with the help of French company Alcatel-Lucent, and "ETECSA is using the cable to reach Telefonica service in Venezuela," he said.
The ALBA-1 cable was strung from Venezuela nearly two years ago with great fanfare, but authorities soon fell silent about it amid whispers of purported corruption and embezzlement involving the project.
Cuban officials have not responded to requests for comment about the status of the cable. In the past, the government has said it would be prioritized for usage in the public interest and for social good.
Until now, Internet in Cuba has been through satellite links that are slower than fiber.
The island ranks second-to-last in the world in Internet connectivity, according to one study.
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