After starting my Windows 8.1 laptop, if I go to the Control Panel\Network and Internet\View Network Computers and Devices, a device is listed that is not on my network. It is listed as either a Ralink wireless client Model # RT286U, a full_ariel Model KFARWI, or a Linksys Wireless Router Model WRT110 and if I right click on the device and select the properties the Model #, Name, and MAC Address are shown. I checked the Device Manager and it was not listed in the Device Manager. Also, my router did not show it as an attached device. I have Win 8.1 laptop, a Win 7 laptop, an iphone, android phone, ipad, WD NAS, and HP wireless printer connected to a Netgear AC wireless router with MAC address filtering enabled. None of the devices I have on my network have the MAC address listed for any of the devices. After a short period of time the device disappears. I have set up my network as a private network. I have my router & computer in my basement.
What is puzzling is the devices don't show up as attached to my router and also do not show an internet or workgroup connection. I have run several tests from GRC and also from the Technicians Toolbox and everything shows my computer and network to be secure.
I am somewhat disturbed by the fact my computer picks up the devices' MAC. Does that indicate that there is some communication (request - answer) between my computer and the unknown device? I am trying to figure out if the device is making it through my Win 8.1 Firewall or my wireless adapter is just picking up its' transmission (my computer is acting like a radio receiver). If the latter is the case then why do numerous networks (routers) in my area that show up when I click on the networks icon not show up as connected to my network also. The fact that the MAC information (which I believe is OSI layer 2 information) is being received makes me wonder if the device could be using one of the tunnelling protocols to get through the firewall? I am running my Firewall with the default settings.
My concerns are: Are the devices a security issue and can they access my network? How come my computer detects them? Since the devices do not list either a work group or a network location so am I correct in assuming the devices are not connecting through my router? Is there anything I can do to prevent them from being detected?