Jitender, I believe its because of the proprietary protocol in action as you know WS EMS works with AlwaysOn, whereas a VNC client employs Remote Frame Buffer protocol (RFB).
AlwaysOn is designed for securing the communication while still keeping the low latency bi-directional communication yet reducing power consumption and bandwidth. Yet you have the RESTful HTTP interface, allowing other applications to communicate to it. Thus extending the reach to the edge devices which provide minimalistic platform for a software to execute
RFB is a simple protocol mainly designed for GUI later evolved to include features like file transfer and compression. That's why you need VNCServer or SSH or MicrosoftRDP for doing remote desktop to the Edge device running WS EMS.
Hope this helps.
Hi jitender hooda ,
I am trying to give in brief uses/advantages of Tunneling. Considering Thingworx as an IOT application providing connectivity to huge number of devices and sensors.
Few important advantages are :
- A tunneling protocol allows a network user to access or provide a network service that the underlying network does not support or provide directly.
- One important use of a tunneling protocol is to allow a foreign protocol to run over a network that does not support that particular protocol; for example, running IPv6 over IPv4.
- Another important use is to provide services that are impractical or unsafe to be offered using only the underlying network services; for example, providing a corporate network address to a remote user whose physical network address is not part of the corporate network.
- Because tunneling involves repackaging the traffic data into a different form, perhaps with encryption as standard, a third use is to hide the nature of the traffic that is run through the tunnels.
So for your question above , if we consider 3rd point , we are somewhat able to correlate why tunnel session is created for EMS server.
Let me know if you find this helpful.