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Hi,<br />
But i guess its main use there also will be to find out the public ip address of the host.<br />
So my question basically is how does the public ip of the host reaches the STUN.<br />
Where is this public ip stored in the packet transfer ? <br />
<br />
Even if it was not &nbsp;STUN server &nbsp;but some other public server say X. Will then also X will know the public ip of host ?
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@Rohit Bajaj - A STUN server is not used everywhere and has application where I suggested. Do you need more information to close this question
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HI,<br />
Here is my understanding of STUN.<br />
Device A which is behind NAT wants to discover its public ip address so sends a request to STUN server.<br />
<br />
A-&gt;B-&gt;C-&gt;D (public ip) -&gt; E-&gt;F-&gt;G-&gt;STUN server<br />
So the request flows till D which is last router having private ip address with a WAN facing public ip address.<br />
When one says about discovering its public ip address i think this ip of Device D is what we are talking about.<br />
Now the request flow through several machines on internet E , F and G and finally lands on the public STUN server.<br />
<br />
what i understand is the Packet that stun server recieves will only have info that it came from G ??<br />
So as per that how does STUN server knows that it has to send the public ip (of D) in the response ?<br />
<br />
Please clarify. I know my understanding has gaps somewhere....<br />
<br />
Thanks
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HI,
Here is my understanding of STUN.
Device A which is behind NAT wants to discover its public ip address so sends a request to STUN server.

A->B->C->D (public ip) -> E->F->G->STUN server
So the request flows till D which is last router having private ip address with a WAN facing public ip address.
When one says about discovering its public ip address i think this ip of Device D is what we are talking about.
Now the request flow through several machines on internet E , F and G and finally lands on the public STUN server.

what i understand is the Packet that stun server recieves will only have info that it came from G ??
So as per that how does STUN server knows that it has to send the public ip (of D) in the response ?

Please clarify. I know my understanding has gaps somewhere....

Thanks

How does the STUN server helps discover the device public ip address

Transmission Control Protocol/Internet Protocol (TCP/IP) is the set of networking protocols that define end-to-end connectivity specifying how data should be packeted, addressed, transmitted, routed and received at the destination. This functionality is organized into four abstraction layers which are used to sort all related protocols according to the scope of networking involved.

TCP/IP

Networking is the process of connecting computing devices, peripherals and terminals together through a system that uses wiring, cabling or radio waves that enable their users to communicate, share information and interact over distances. Often associated are issues regarding operating systems, hardware and equipment, cloud and virtual networking, protocols, architecture, storage and management.

Networking

The variety of Linux distributions creates myriad issues relating to configuration and operations when computers are networked, not the least of which is the use of various network management applications, some of which are included with specific distributions, while others are standalone applications.

Linux Networking

Networking software modules are interfaced with a framework implemented on the machine's operating system that implements the networking functionality of the operating system. The best known frameworks are the TCP/IP model and the OSI model. Systems typically do not use a single protocol to handle a transmission. Instead they use a set of cooperating protocols, sometimes called a protocol family or protocol suite.[9] Some of the best known protocol suites include: IPX/SPX, X.25, AX.25, AppleTalk and TCP/IP. Other protocols indirectly related to networking include the hypertext transfer protocol (HTTP) and its related technologies, Dynamic Host Configuration Protocol (DHCP), Domain Name Server (DNS) and other Internet protocols.