How Send Data Between Two Devices Using Sockets In Python?

I'm using this code for the client: import socket HOST = 'Server IP' PORT = 5555 s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) s.connect((HOST, PORT)) s.sendall(b'Hello,

Solution 1:

The short answer is that you can't -- most routers connected to the Internet these days include a firewall and/or NAT, both of which are explicitly designed to prevent Internet packets from the outside world from getting to devices on the local LAN, for security reasons. In particular, the private addresses assigned to devices on the LAN (192.168.1.5, 10.0.0.10, and so on) are non-routable, so they are not meaningful outside the context of the local network and cannot be used to route traffic across the Internet.

Obviously that's not the full answer, though, since various peer-to-peer programs in use today (e.g. Skype) do manage to communicate in the way you want to do; however, they all have to work around the above problem one way or another. Some ways they do it include:

1. Have the user of the LAN that is to receive the incoming TCP connection configure port forwarding on his router. This tells the router that any TCP connections received on a particular port should be automatically forwarded to the specified private IP address on the LAN. Downsides of this approach are that it opens a hole in the user's firewall that might be later exploited by bad actors, and that many users aren't willing (or even able) to reconfigure their routers in this way.

2. Run a server with an Internet-facing IP address, and have your program always connect to it. This server can then work as a proxy, forwarding TCP data from one connection to the other as necessary. This avoids the problem, at the cost of having to maintain your own 24/7 public-facing server and route all your traffic through it.

3. Use TCP hole punching to convince the router(s) to allow your incoming TCP connections by exploiting the rules/logic they (sometimes) use to decide when to allow incoming traffic. This gets you the direct connections you want, but it's fairly complicated to set up, doesn't work on all routers, and generally requires the implementation of step (2) (above) as a prerequisite, since the connection-bootstrapping process itself requires some communication that must be facilitated by a third-party.

Solution 2:

to work, change s.listen() to s.listen(5)

I was able to connect from my network 192.168.1.x to other 192.168.2.x

Now, depending of your requirements you will need some configuration to work in the Internet.

the clients should have the IP depending the localization of your server, if server application is:

• Connected direct to the Internet, client should have gateway IP address
• Connected to a router, you can configure a DMZ (not recommended, not secure, just for tests) or configure ports (secure and recommended), the clients should have the gateway IP address of the router