Comments by Member 10860651 (Top 1 by date)

I found this:
http://www.asp.net/signalr/overview/deployment/using-signalr-with-azure-web-sites#websocket
And this:
https://azure.microsoft.com/en-us/blog/introduction-to-websockets-on-windows-azure-web-sites/
Note this part:
WebSockets Connection Limits

Currently Azure Web Sites has implemented throttles on the number of concurrent WebSockets connections supported per running website instance. The number of supported WebSockets connections per website instance for each scale mode is shown below:

Free: (5) concurrent connections per website instance
Shared: (35) concurrent connections per website instance
Basic: (350) concurrent connections per website instance
Standard: no limit
If your application attempts to open more WebSocket connections than the allowable limit, Windows Azure Web Sites will return a 503 HTTP error status code.

Note: the terminology “website instance” means the following - if your website is scaled to run on (2) instances, that counts as (2) running website instances.