问题
I have a wpf app that needs to communicate(exchange data) with a custom designed device (we can modify the code for the device). Do I have any options to connect to the device if it is behind a firewall via http? I was hoping there would be a method where the admin would not have to forward any specific ports or do anything on his end. I assume the issue is how would I address the device from my app. I know SOAP over SMTP is one option. Is another option where the device could chatter out to my application via http?
回答1:
UPNP is supported by some firewalls to simplify this. Otherwise you are usually stuck opening ports on the firewall manually or using some 3rd party proxy server for a rendezvous server.
回答2:
This problem is solved by relay services like Yaler or My-devices (I did not test this last one).
回答3:
A lot of firewalls are setup to allow access on port 80 (HTTP) otherwise the users wouldn't be able to browse web sites on the internet. You can try and see if port 80 is open to traffic. If you can modify the code for both the device and the client you can use port 80 to communicate with your own protocol - you don't necessarily need to use HTTP.
回答4:
Any kind of RESTful architecture over http will do it. If this is the best option for you depends on what APIs / libraries are available on your custom device.
来源：https://stackoverflow.com/questions/2529941/connecting-to-device-behind-firewall