Radio Silence is a network monitor and firewall for the macOS. The software stops apps from making network connections. The firewall runs in the background and does not require an open window.
SaaSHub's Down Detector checks the status of services automatically and regularly. However, we cannot promise 100% accuracy. That is why we depend on user reported issues as well. The Activa status here can help you determine if there is a global outage and Activa is down for everyone or it is just you that is experiencing problems. Please always report any issues to help others know the current status.