Introduction
Chorus is an modern web application that makes use of advanced features within the HTTP protocol. We have created a test page that will check if your network is capable of providing the features needed for a smooth experience using Chorus:
https://your-chorus-site-address/network/
Please leave the page running for 30 seconds to gain sufficient data about how your network performs.
Tests that do not give a result of 'OK' are indicative of a problem with your network configuration.
Speed results can be considered 'good' if the 'Average RTT' is in the hundredths of a second range e.g. 0.0235 is a good result but 0.19 is considered slow and you may experience unpredictable user interface issues on slower networks.
Background about the tests
WebSocket Test Results
This section tests whether your network allows 'websocket' connections and tests the speed of those connections.
If websockets are not permitted by your network, expect performance to be sub-optimal. Chorus will attempt to use a fall back mechanism to communicate with a user's browser but this should not be considered a long term solution and your proxy should be reconfigured to allow websocket communication.
CORS Test Results
The CloudFront delivery network may be used as a caching proxy service in front of Chorus sites. This helps improve the performance of Chorus as static content has a shorter distance to travel to the user.
Content from Chorus will therefore be sent to the user from two different locations:
1) e.g. https://yoursite.chorus.thirdlight.com
2) e.g. https://d1br04p5jdm344.cloudfront.net
There are two different origins of resources and the security restrictions in modern browsers require the application (Chorus) to acknowledge that the CloudFront domain is acceptable otherwise the browser will block resources from loading from this "foreign" origin. Chorus does this by making use of the "Origin" HTTP header as part of its CORS (Cross Origin Resource Sharing) checks.
You must make sure that any proxy server on your network does not block this header and that all the CORS checks on https://your-chorus-site-address/network/ give a status of 'OK'.
Please also be aware that the CORS tests performed by https://wtest.chorus.thirdlight.com only perform tests against corstest.chorus.thirdlight.com and do not test CORS requests to CloudFront so any changes you make to allow CORS tests to pass must be made to both sites.
Potential causes or poor performance
Upload times are typically beyond Third Light's control as they rely on the capabilities of external networks between your browser and the Third Light server. We only control the last link in the chain if your system is hosted on our platform so the problem may lie on an intermediary network that Third Light have no influence over.
If you are working from home and connect via your organisation's VPN, try disconnecting from it and performing the operation again. It maybe that the VPN is a limiting factor.
Other types of proxy server on your network may also negatively affect performance. Please work with your IT team to establish if a proxy is present, whether it has an issue or has been configured to restrict your network connections.
