Can my neighbors use my DSL Wi Fi ?? Do they need a code to sign in ??
How do I make sure its secure ??
The general answer is that your neighbors can indeed use your WiFi if you don't have any security turned on.
There are a couple of relatively easy ways to secure your Wi-Fi network. The first is to enable WEP encryption.
This requires users of your Wi-Fi network to know the password. While you can select 128 bit encryption, the reality is that 64 bit is just as likely to keep out the neighbors. Anyone who has the ability to easy 'break' the 64 bit encryption probably can also break 128 bit encryption. Since the encryption is software, the longer encryption also tends to degrade performance.
In its simplest form, you just pick a 5 character password, and turn on WEP in the router. (http://192.168.1.1 and login as the administrator). Your instruction manual should tell you what the default administrator name and password are, or how to figure them out.
The other relatively easy way to secure your network is to use MAC authentication. Each wireless (and wired adapter) has a unique Media Access Controller or MAC address. I believe the MAC address is 48 bits, so there is no realistic possibility of guessing what it is. With MAC authentication, only the MAC addresses on the list can use the network. There is no password. If your MAC address isn't on the list, the WiFi network simply won't talk to you, period, end,stop.
That's the good news. The bad news is anytime you want to add a new computer, or remove one, you have to go into the router and add or delete the MAC address.
While WPA encryption is more secure than WEP, the reality is any of these steps will keep your neighbors from using your Wi-Fi network.
I believe the MAC address is 48 bits, so there is no realistic possibility of guessing what it is.
No guessing what the valid MAC Address is (or) MAC Addresses are.
Oh please, get real. You have no idea of what you are talking about.
MAC Address(es) regardless of the type encryption is always sent in the clear!
So what this means is, with TKIP on a network, that after 12 minutes it is possible to take a small packet - and the reason it has to be small is they have to know everything about the packet. That is, the MAC addresses are not encrypted. They exist at the front of the packet before the encryption begins because you have to have the MAC address in order for it to come or go.
TKIP is the older and less secure of the two security protocols offered within the WPA and WPA2 WiFi Alliance certification standards.
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