Network Speed Tests and your Connection to Xbox Live

I saw this article on Lifehacker and wanted to start a discussion while highlighting speed tests and connections to Xbox Live.
The article does a good job of pointing out why you can get wildly different results from different speed tests, and even the same speed test tools for different tests, and even more so, you can get different results from different browsers! This can be very
frustrating when you're trying to gauge if you're getting the speeds you feel like you should from your ISP, troubleshooting performance issues, or just curious on how high those numbers can go.

The three main metrics that are reported with speed tests are latency, download, and upload.

Latency is an easy one, and shouldn't change too much between tests from the same source. This measures the time that it takes from your network traffic to get from your computer to the testing server. So if you're on the same tool performing multiple
tests the number should remain relatively the same, with small variance. This can vary greatly between tools, since they're using different servers, which will require that your traffic travel a different route, involving different physical distances, connections
and factors along the way.

Download speed is usually determined by the test tool requesting a connection from your computer and analyzes the time it takes for your computer to say its done, and then adjusts the size of the data it's sending, and continues to monitor the time and
adjusting the data until the time is up. Upload is usually measured similarly, but in the reverse of the download test. Sending data form your computer to the server.

Now, there are a lot of different pieces between your computer and the testing servers. At each hop, the networking equipment has to handle multiple connections, and process where the traffic has to go, finding out where they should go, establishing connections,
sending the traffic, etc. So from your computer to your router/modem/network device to your ISP, and all the hops between them and the destination affect the response you get back, which can lead to some wildly varying connection statistics.

In addition to all that, speed tests are just sending groups of arbitrary data. Nothing that needs to process, send back and forth, provide input for the game or app you're running. When you're connecting to Xbox Live, you're connecting to their service
and the traffic is handling notifications, messages, voice chat, achievement data, friend status, etc. They manage to do this with a VERY small footprint of data for what they provide, and I, for one, find that very cool.

With Xbox Live, there are also different services and connections handled in different ways. Friend status, profiles, achievements, are handled with Xbox Live network proper, while

if you're handling a game or app download, that would come from a Microsoft Content Delivery Network (CDN), and the CDNs will have different end-points and connections. Beyond that, when you connect to a multiplayer game, Xbox Live is handling the friends
list and related parts, but it only brokers the connection to the games multiplayer servers and services which are built and controlled by the developer and publisher of the game.

All this and I'm not even going into the internet backbone, and how that affects your traffic, as there is your ISP, the distant end ISP, and the backbone in between,
but is very interesting to read about. Additionally there is the download speed tier you're sold by your ISP,

which is the maximum theoretical, and what you actually get, which is pretty well outlined in the first article as well as this one.

All this to really just point out that: Networking is hard. Running a global gaming network connecting people all across the world is orders of magnitude harder. There are so many moving pieces, so just try understand them and step through them if ever
trying to troubleshoot your connection, or if you're trying to identify why your performance is not what you expect, and that speed tests can sometimes provide conflicting results from what you expect.

TL;DR. Xbox > Modem > ISP > Internet Backbone > Distant End ISP > Distant End > Multiplayer Game/Service/Content and back again. The stepping stones between you and your Fortnite dance.

:)