[closed] Is it possible to find out how data are encrypted on a LAN connection?

Hello everybody,

I would like to know if it is possible to understand the data sent on a package through a LAN.

Let me explain you my problem, I have two devices connected thanks to a local network (10baseT) and using the IP/TCP protocol. As advised on the Internet, I captured package by using Wireshark and laptop that I connected to the hub located between the two devices.

Indeed, I was able to follow the TCP stream related to the LAN connection. However, the data on the stream are not understandable as they are.

So, I think that the data must be somehow compressed or encrypted before being sent. But, how figure it out?

If anyone has an idea, I'll gladly read it!

Thanks and sorry for my awkward English ;p