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[KB870]LIMITED WEBVUE PERFORMANCES WHEN HOSTING THE WEB SERVER ON WINDOWS 7 OR WINDOWS SERVER 2008 R2

Tags: IIS, Webvue

WebVue
7 years ago
By BL
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Applies to:

PcVue 12 onwards
Summary:

Degraded performances of WebVue, in particular, limited responsiveness when the Web Server is hosted on a Windows 7 or a Windows Server 2008 R2 computer. The IIS version coming with Windows 7 and Windows Server 2008 R2 does not support the WebSockets protocol. Hosting the WebVue server on a not-WebSockets-enabled Windows system is only recommendable for projects with a small to medium level of dynamization within the HMI.
Details:

WebSockets is a full-duplex, bi-directional communication protocol, which allows both communication partners to exchange messages asynchronously in both directions (client to server and server to client).

By default, the WebVue client takes advantage of WebSockets to deliver an optimal user experience.

If the web server does not support WebSockets, the WebVue client falls back to a communication pattern called long-polling.
In practice, the client polls the server and waits for feedback from it. The server does answer the request unless there is new data available that it may send to the client. As opposed to WebSockets this is traditional client-server operating mode and the way of exchanging messages is sequential. Comparing the two communication modes, obviously, long-polling cannot be as powerful as WebSockets.

Created on: 15 Jan 2018 Last update: 30 May 2024