How Yandex Internetometer measures speed

Yandex Internetometer tests your download and upload speeds using a two-step process:

1. Selecting servers for the client to run the speed test.

   We run all connection speed tests through Yandex CDN, which has servers located across Russia and in other countries.

   These servers are selected based on a comprehensive analysis of the following parameters:

   • Network routing metrics generated from BGP data.
   • Our internal ranking of locations.
   • Your IP address.
   • Current load on our CDN servers.

   As a result, we select 1–3 servers that provide the best performance for the specific user based on Yandex CDN algorithms.

2. Running the speed test.

   We measure the following parameters using the selected servers:

   • Download speed.

     Test algorithm:

     1. We select the three closest CDN servers.
     2. Your device simultaneously downloads data from these servers.
     3. Every 100 ms, we measure the total volume of data received from all three servers during that interval.
     4. We calculate the transfer speed as a moving average based on these total values.

   • Upload speed.

     The test algorithm is similar to the download speed test. We use the same servers for this test.

   • Latency.

     We use the TTFB metric to evaluate latency.

     Test algorithm:

     1. We take measurements on already established TCP, TLS, and HTTP sessions.
     2. Your device downloads small files multiple times (their size is tailored to minimize the impact of bandwidth and focus specifically on latency).
     3. We record the TTFB value for each test. We also factor in the results from previous speed tests.
     4. From this set of measurements, we select the lowest TTFB value as the final latency metric.

Speed test and server selection nuances

• If the server closest to you is overloaded, the system might prefer a different node.
• If your client supports both protocols (IPv4 and IPv6), we run the tests and route the traffic over IPv6.
• A speed of 20 Mbit/s is considered optimal for streaming 4K resolution videos (with standard encoding parameters).