Dear Valentina,

Thank you for reviewing.

> > For this, export function, connection is established from 
device-side
> machine to application-side machine.
> >
> > Following use cases are supposed for the export function.
> > 1) Server application or cloud service serves distributed ubiquitous
> devices.
> > 2) Dedicate devices to server application or cloud service.
> >
> > To connect to cloud service, it needs to connect from inside of 
firewall.
> >
> 
> Could you please provide some more detailed examples of use cases for 
this
> feature?

OK. In figure below,

   Home/SOHO/Intranet                Internet
                         +--------+            +--------+
 +------+   +------+     |Router, |            |Internet|
+|device|---|Linux |-----|proxy,  |------------|service |
|+------+   +------+     |firewall|            |on Linux|
+------+   controller    +--------+            +--------+
ex)
Device                                      Service
 sensors ................................... environment analysis
 cameras ................................... monitoring, recording
 ID/biometric readers ...................... authentication

Connection from outside firewall is usually blocked.
So existing import request sent with attach command doesn't work.

                         (blocked)|| <--------- # usbip attach

Firewall opens some ports, usually HTTP(80) and HTTPS(443), from inside.
Then export request sent with new connect command works. 

# usbip connect  ------------------------------>
                         (passed)

Also, router doesn't route raw IP packets to outside. Some application 
protocols are needed. DNS client is needed and proxy may be used. 
Firewall or proxy may check application protocol. HTTP is the most 
usual accepted application protocols.
Succeeding patches allow to wrap raw TCP packets with WebSocket which 
are commonly used to encapsulate packets in HTTP connection. The last 
patch introduces WebSocket including DNS client and proxy.

NOTE: I posted v2 of this series of patches on 14 Apr 2015.

Thanks,

n.iwata
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