Strange Router behaviour

[#1]

Not sure if this is the right forum to post this but I have a Billion 7800n router in use with my PNet account. On the router there are lights and one is specifically for showing Wireless connection. My PC is connected via ethernet and has no wireless card. My wife uses the wireless connection on her laptop upstairs. I always know if she is connected because the wireless light on the router will flicker on and off, and also if she is downloading or watching a video clip then it flickers rapidly.

My concern is that this morning the wireless light was flickering constantly indicating activity but her laptop was switched off completely except for being plugged in to the mains.

Does this indicate someone else has access to my wireless connection? I have in the past used software to see who is on my net but it never shows anyone else but only my PC and my wifes laptop.

Would appreciate some guidance on this. I am not paranoid but just want to know if i am being intruded !

[#2]

if you login to your router then status and DHCP does it show anything odd

[#3]

I have done as you suggest but have no clue as to what I am looking at ! What should I be looking for. I t shows my wife's laptop, my PC and my Kindle under Clien Host name but there is one where the name is blank but there is a MAC address. Should that one be identified with a name just like the other 3 are. ie. Kindle etc?

[#4]

I also have that but it doesn't have anything in the Mark Column indicating that it isn't wireless but I don't know what it is. I did wonder about the Samknows whitebox but that obviously isn't the case if you don't have one

If you look under ARP it will tell you what is currently connected

[#5]

OK thanks Oldjim. I will look at ARP the next time I see this type of mystery activity. I just looked now and it only shows me connected which is correct. The strange behavior stopped a an hour or so ago.