How can i tell if someone is using my wireless and if they are can they snoop on my info? How do I stop this if it’s happening?
most rosters have a MAC address table of all attached devices. you can easily see unwanted visitors. turn off broadcast SSID, disable guest account, and implement security protocols (WEP, AES, etc,) whichever your router supports
Type your IP address on your browser and you will see a list of Mac addresses with corresponding names of the gadgets connecting to your Wifi. If the number of addresses is more than the number of gadgets at home connected to Wifi at that moment and most probably it is owned by someone else.
I have caught a neighbor using this. :D
Do you know how to log into your router? It should be as simple as typing your router's IP address in the browser, though there also might be software on your computer for managing it. Anyway, when you get in you can see who is currently connected, based on Mac address.
Do a search for "who is on my wifi" and it will return several programs that will monitor your network. you are going to have to identify all the MAC addresses in your house. (phones, computers, gaming systems, TVs, boosters/routers, anything else you might have)
Here is an example I use from time to time. http://download.cnet.com/Who-Is-On-My-Wifi/3000-18508_4-75179802.html
If you want to lock your network down, you should use MAC filtering. then, only computers that you say can be on your network can get on it. Every other computer is locked out of it. Also, as Bruce E said, you should turn off your SSID broadcasting. (Its a good idea to do this anyway. Its just more secure and will stop most casual war driving.)
Wireless Network Watcher can alert you if strangers are on your network
Install go to Options then select Beep On New Device and Background Scan.
Start with these MUO articles:
You can check the logs in your wireless access point or router to see the MAC addresses of the machines that are connecting. Any MAC address that doesn't match one of your own devices is suspect.
If someone is connecting to your WiFi, they can snoop on your traffic.
To stop it, you can change your SSID and password for your WiFi (and all of your devices) and disable any guest access to your network.