It works like this:
- Randomly checks every seednode 4 times per day;
- Based on their "quarter daily hourly" uptime, a daily uptime percent is computed;
- While the time between probes is not an exact quarter of a day, the randomness of the probes is computed in a way that will compensate to a normal average on a 30 days monitoring period;
- Based on their "daily" uptime percent, a monthly uptime percent is computed by adding (SUM) all daily uptime percents and dividing the result to the number of days each seednode has been monitored for (simple average);
- The "current" monthly uptime percent is computed and displayed for the previous month;
- The hourly uptime stats are deleted every day *after* the daily stat has been computed, the daily stats are deleted once every 30 days *after* the monthly stat has been computed;
- All monthly stats are archived and never deleted - they can be browsed easily on the archive page;
- We check from 2 (two) different geo-locations (different IP addresses / countries / AS numbers). Ocasionally, we change the IP addresses / countries / AS numbers;
- We assume a seednode is DEAD permanently if it's not up for at least 40% in a monthly stat for 2 consecutive months. Note that this can change in the future;

A Freenet node is not easy to monitor if it's up and running, like running a simple port scan or a PING, because, you know, it's ***anonymous***, and Fred (Freenet Reference Daemon) will not respond to queries on the OPENNET port if provided with garbage, especially to prevent probing by adversaries. We use a script that simulates a Freenet node to test them, which is available here.

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