Latency and Expected Speeds: WiFi vs. Wired Connections Explained

What is Latency? 

Latency is the delay or lag between actions on the computer and the response you see on the secondary device when using Luna Display. Essentially, it is the amount of time it takes for movements on the computer, such as moving the cursor or clicking on a file, to be reflected on the secondary device's screen. 

Lower latency means less delay, resulting in a more immediate and responsive experience. High latency can make the interaction feel sluggish or out of sync. Luna Display aims to minimize latency so that the actions you take on the computer are quickly relayed to your secondary device, providing a smoother and more real-time experience.

What are the different ways I can connect my devices with Luna Display? 

You'll have the option to connect your primary and secondary devices using the following methods: 

WiFi Connections

• Connect both of your devices to the same WiFi Network
• Connect an Ethernet cable from one of your computers directly to your router - this will qualify as a WiFi connection

Wired Connections

How do I use a USB, Ethernet, or Thunderbolt connection?

When using Computer-to-Mac mode: 

• Connect an Ethernet cable directly between your two computers
• Connect an Ethernet cable from both computers directly to your router - this will qualify as a wired connection

When using Mac-to-Mac mode:

• Connect a Thunderbolt cable directly between your two computers
• Connect a USB cable directly between your two computers (both computers must meet the requirements: USB Support for Mac-to-Mac Mode)

When using Computer-to-iPad mode: 

• Connect a USB cable that is capable of data transfer directly between your computer and iPad

Peer-to-Peer Connections

When using Mac-to-Mac or Mac-to-iPad mode: 

• Connect your devices using Peer-to-Peer mode (both devices must meet the requirements: Using Peer-to-Peer with Luna Display)

How much latency can I expect when using a wireless or wired connection with Luna Display? 

WiFi Connections

How can I improve my wireless connectivity?

WiFi connections should yield latency measurements of around 7-25ms, with an average of about 11.5ms. While these latency speeds are not as fast as when using a wired connection, you should still see improved performance as compared to other programs, such as Duet Display (95ms) or AirDisplay (53ms). 

If you notice lag or latency issues when connected via WiFi, we would recommend connecting your devices using a cable for better performance. Every person's network environment is unique, so there may be outside factors causing latency issues with your connection. These typically include the age of your router, the number of walls in between devices, how many devices you have connected within your network, etc. 

Wired Connections

Wired (Thunderbolt, Ethernet, and USB) connections should yield latency measurements of around 1-4ms. This is extremely fast and you should see minimal lag when properly connected using these methods. 

Please be aware, latency will never be 0ms. Given this, it is still possible to see moments of lag when using Luna Display. This is especially true if your computer's system is taxed by using multiple graphic-intensive programs at the same time (ex: YouTube, Photoshop, Illustrator, CAD programs, etc.) or your computer is older and running out of memory. 

How do I check latency in the Luna Display application? 

To check the latency of your connection in Luna Display, open the Luna Primary and Secondary applications. While the applications are open and active, on your primary device, copy and paste the follow link into a browser or simply click on this link: http://localhost:44557/vitals

The Vitals window will pop up on your screen; you will see two graphs stacked on top of each other (one with latency and the other with throughput). Latency will be displayed on the top of the screen in a cyan-blue color. You should also see the connection type listed on the top right-hand side of the screen. 

What can increase latency in wireless and wired connections? 

WiFi Connections

• Distance from the router: The farther your devices are from the WiFi router, the longer it takes for the data to travel
• WiFi signal strength: If the WiFi signal is weak or experiencing interference due to obstacles like walls or other electronic devices, it can lead to higher latency
• Network congestion: When multiple devices are connected to the same WiFi network and consume bandwidth simultaneously, it can cause congestion on the network and cause delays
• Bandwidth limitations: If the WiFi network has limited bandwidth capacity, it may struggle to handle high data volumes, resulting in less data being transferred 
• WiFi channel interference: If neighboring WiFi networks or devices are using the same WiFi channels, it can introduce interference and impact latency 
• WiFi protocol and technology: Older WiFi protocols like 802.11n may have higher latency compared to newer protocols like 802.11ac or 802.11ax (Wi-Fi 6) due to advancements in technology and improved efficiency. We recommend using a modern wireless router that supports 802.11ac and connecting to the 5GHz frequency band when possible

Wired Connections

• Integrity of the cable being used: Using a faulty or damaged cable can cause interference between devices, causing higher latency
• System performance: The processing power and performance of the connected devices themselves can impact latency. If the devices are underpowered or overloaded, it can result in slower data processing and higher latency between devices
  
• Distance and cable length: Longer cable lengths can introduce signal degradation and latency. It's important to ensure the cables are of appropriate length and properly inserted into the ports of your devices
• Cross-talk: Cross-talk occurs when signals from one cable interfere with signals on adjacent cables