LAN addresses

Question

how to get IP addresses of all users in local network or network created by Dial-up connection (remote access)? I tried IPHostEntry heserver = Dns.Resolve(Dns.GetHostName();); foreach (IPAddress curAdd in heserver.AddressList) { client.Send(Encoding.Default.GetBytes(s), s.Length, curAdd.ToString(), 30000); } but 'heserver.AddressList' contains of only my current IP...