Quote Originally Posted by Vis3R
ok ... well i think there is a problem with IP cause there's no server ... how will you know the IP of your friend? ... asking him every time you want to connect to him what his ip is isn't very usefull ... if you set a host to your IP .. like .... myclient1.no-ip.org ... he can always connect to it whatever your IP is ...

about the data encryption ...
let's say i sniff your data like "ߣߤ¨ßŁłŁł|€|!" (the data yoru client encrypted) .... even if i have a custom made client i won't be abble to know what that means to your client ... i won't be abble to add another one .... cause i won't be able to encode it (if u do a good encryption) ...

You let people know your IP address by broadcasting it across the network, and if your friend recieves your broadcast message, retrieves the ip address and establishes a connection with you... generally from what I've learnt you can get mini-servers. For example you broadcast it a short distance, someone on the network picks up your message and forwards it onto people that they know and perhaps they broadcast it onto there network, and anyone on that network may try to reconnect back to you, but broadcasting only travels so far to prevent flooding. Have a read, http://en.wikipedia.org/wiki/P2P if your not familiar with it. I believe the Gnutella uses the mini-server style above, not sure about KaZaA.

All transmission has to be initially unencrypted so that you can establish the connection....atleast I think so... unless you encrypt the message with your hash saying that you've connected, then only those who know your hash would be able to tell who it is..perhaps.. the broadcast message would have to contain say a command identifying it as someone coming online, and then the second argument would be a hashed string that you would have to be able to decrypt, which would have the ipaddress of the sending computer (not sure if when I broadcast if the packets will contain my ip address?)