The American internet speed-testing service is a threat to national digital security, Roskomnadzor has said Russia’s media and communications regulator, Roskomnadzor, has blocked the internet performance measurement tool Speedtest, run by US-based company Ookla, citing threats to national digital infrastructure.In a statement on Wednesday, the agency said access to the service was restricted “due to identified threats to the security of the public communication network and the Russian segment of the internet.”Speedtest, one of the most popular internet speed-testing platforms globally, boasts millions of daily users. Roskomnadzor has recommended Russian users switch to a homegrown alternative called ProSet, developed as part of the country’s broader push toward digital sovereignty.Russian authorities first signaled a potential ban on Speedtest in October 2024. At the time, the regulator warned the service could be blocked if it was found to compromise the stability, integrity, or safety of domestic networks. The Russian Izvestia newspaper cited a report by industry think tank the International Communications Academy (ICA) that Ookla could be sharing data gathered through testing Russia's digital infrastructure with US intelligence agencies, thus increasing the risk of cyberattacks.The ICA’s proposal to ban the service was supported by both the State Duma and the Federal Security Service, the paper noted.The concerns have been echoed by the Public Communications Network Monitoring and Management Center, an entity subordinate to Roskomnadzor. “The data collected by the US service may be used to plan, organize, conduct, and evaluate the effectiveness of attacks on Russian telecommunications networks, as well as on entities connected to them,” the center stated on Wednesday, as quoted by Vedomosti. The Russian authorities have already fined Ookla twice for violating data localization laws. In July 2022, the Seattle-based company was ordered to pay 1 million rubles (roughly $12,000) for failing to store Russian users’ personal data on servers located within the country. A repeat violation led to a second, larger fine of 6 million rubles (about $64,500) in October 2023.The Speedtest ban follows a major cyberattack on Russian airline Aeroflot earlier this week, which disrupted airport operations and led to widespread flight delays. Pro-Ukrainian hacker groups have claimed responsibility for the incident, and a criminal case has been launched.