In answer to both questions, the answers are to be found in the following abbreviations: A.R.P. and R.A.R.P. This is to say, that routers and such use Address Resolution Protocol and Reverse Address Resolution Protocol to query a given I.P. Address or MAC address if given the other one. Because you are frequently dealing with situations like D.H.C.P. ( Dynamic Host ) where the IP address changes according to what address just happens to be unused in a pool, you could obtain a list of possible MACs given a ‘nearby’ connection was made. With multiple machines and added Authentication, you have pretty slim chances with a mobile client. This can theoretically happen, yet I would not want to wait for a result or trust it through a WiFi system. Nearby means on the same physical Ethernet segment, etc. If you knew enough about the machine, you might start be reading the following forum post: Windows CPU Temp where bvaldinos asked about remotely reading temperature from a connected machine. Mr. Zx… knew of a Vision ( not Perspective ) way to query the hardware, and the similar post ( battery percentage ) has a link to a website with more information about hardware queries.