Indoor Bike Improvement #6 - Better Internet Connections

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6 of 10 - Better Internet Connections

Zwift leverages wireless connections that include a mix of Bluetooth, Ant+ and WiFi. They tend to be concentrated in the busy 2.4 GHz wireless frequency band. As we will see below, it's a good idea to move these connections to the less crowded 5 GHz band.


Overcrowding in the 2.4 GHz band causes data dropouts, decreased performance and failed connections. Bluetooth and Ant+ use the 2.4 GHz band. WiFi (to and from the Internet) can use 2.4 GHz or 5 GHz depending on the device.

The SB20 bike and HRMs use multiple Bluetooth and Ant+ connections. Zwift Play controllers use one Bluetooth connection per controller. All in the 2.4 GHz band. This is not a big concern since the volume of data transferred by these devices is minimal. All these devices combined transmit only a few thousand bytes per second. 



In contrast, the Zwift App and the Zwift Companion app can transfer millions of bytes per second. Performance gains can generally be found around these apps.

Contrary to what you might expect: Wireless connections to a indoor bike are simply not a bottleneck. Some smart bikes have added wired Ethernet connections. This will not yield much of a benefit. The data bandwidth between the bike and an app like Zwift is simply too low. 

I made changes to my iPad configuration to improve performance.  I've included notes on PC/Computer and Apple TV configurations too.

For deeper dive, see my post Wireless is Good - and Complicated.

iPad

iPad configurations, like the one I use, are generally straightforward.


1. All data to and from the SB20 and HRM is transferred with primarily with Bluetooth (Ant+ is used by SB20 internally). As mentioned previously, these are low volume data channels, so no worries.
 
2. WiFi is used for the higher data volumes required by the Zwift app (iPad) and Zwift Companion app (iPhone). Note: Wired connections are generally not used on iPads or iPhones. 

Suggested Optimization: 

5 GHz WiFi offers significant performance increases - especially with the Zwift app on the iPad. Keep in mind: a 5 GHz access point typically needs to be in the same room to deliver maximum benefits.

PC/Computer

PC or computer configurations are the most flexible.


1. Like the iPad configuration, data to and from the SB20 and HRM is transferred with Bluetooth and Ant+ in the 2.4 GHz band. Many computers can support Ant+ (with a dongle) for more flexibility.

2. The Zwift Companion app (iPhone) can use a 5 GHz WiFi connection.

3. Wired Ethernet can be used for the data hungry Zwift app (Computer)

Suggested Optimizations: 

Wired Ethernet with gigabit and higher throughout is a true performance enhancer. 5 GHz WiFi can also help but is not essential in this configuration.

Apple TV

Apple TV configurations are simple - until you run out of Bluetooth connections.


1. Like the previous configurations, data to and from the SB20 and HRM is transferred primarily with Bluetooth. Inconvenient truth: The Apple TV is limited to just 3 Bluetooth connections. In this example, there are not enough connections available to use the pair of Zwift Play controllers. 

2. The Zwift Companion app (iPhone) does not have the same Bluetooth connection limits. It can be used as a proxy to forward data to and from the Zwift Play controllers. It can also use 5 GHz WiFi. For more information, see Connecting Your Zwift Play to Apple TV.

3.Wired Ethernet can be used for the Zwift app running on the Apple TV.

Suggested Optimizations: 

Wired Ethernet is highly recommended for any Apple TV - particularly one that runs Zwift. 5 GHz WiFi will also help the Companion app but is not essential in this configuration.

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