As the chunks are received by the client, the client will request more chunks throughout the duration of the test.The client calculates the real-time speed of the transfers then adjusts the chunk size and buffer size based on this calculation to maximize usage of the network connection.The client requests the server to send an initial chunk of data.

The client establishes multiple connections with the server over port: 8080.

This test is repeated multiple times with the lowest value determining the final result.

The round-trip time is measured is measured in ms (milliseconds). Upon receiving that message, the server sends a reply back. The client sends a message to the server.

This test is performed by measuring the time it takes for the server to reply to a request from the user's client.

If you host your own servers, you also have the option to add those servers to the public Speedtest Server Network to expose your brand to a wider audience. Your server(s) are hosted within your network and associated with your test via your Speedtest Custom account. By using your own server network, only your server(s) will be displayed to your test takers. By using the Speedtest Server Network, thousands of servers around the globe will be available to your test takers. You can leverage the Speedtest Server Network or use your own server network. You have two options for the back end of your test (the Ookla Server Daemon). If you would like to make your test accessible only from the embedded URLs, including those that are accessible only from within your network, you can select this option within your Speedtest Custom account. You can direct your test takers to your test by linking to your subdomain or embedding your test on one or more web page(s) via an iframe. The front end cannot be hosted within your network at this time. The user interface of your Speedtest Custom test (front end) is hosted by Ookla at the subdomain of your choice (e.g. See the Test Components section below for details about the testing methodology.

Speedtest Custom measures download speed, upload speed, ping (latency), and jitter.

It operates over TCP testing using open standards, including HTML5, JavaScript and WebSockets. Speedtest Custom is a web- and mobile-friendly Speedtest that you can customize and publish within minutes.

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