IP addresses & home networking advice

[latrosicarius]

funny thing is that both laptops appeared and it was the xbox the wasnt there....

The DHCP list in routers are notorious for not being up to date. I pretty much ignore it. They will show computers connected which haven't been connected in days -- they will also *not* show computers which you know *are* connected. They will also only ever show computers that obtain their IP addresses "automatically" from the router's DHCP; not the ones where you manually enter what IP to use in TCP/IP properties.

do you know how i obtain the mac address of each device??

Two ways: first, look in your router's DHCP page and it will show the MAC address next to each IP it has served. The MAC address is HOW it assigns IPs. But again, I mentioned above that this page is usually unreliable to give you up-to-date info.

Second, you can go to each PC, and do the following: START > RUN > "cmd"

Then type: ipconfig /all and look for the string of letters and numbers called "Physical Address"

[peterb]

When I say 5 minutes, I'm talking from personal experience of breaking a WEP key on a WEP protected O2 (Thompson) ADSL router. All you need is a Laptop with a Wireless card, a certain Linux Live CD and Google. Granted under 5 mins is someone that has done it before. But 5 mins none the less. Certainly long enough to log is as the Admin user with detail obtained again from google, and change all the settings on the router in question to disrupt someones internet connection.

WPA can be cracked as well, but it takes significantly longer and requires that the key used is a word in a dictionary file. If the Key is a random assortment of upper and lowercase letters numbers and symbols this can be extended to a lifetime.

Both technology's also appear to be quite vulnerable to DOS attacks where you spam disconnect packets at a target device cloning the MAC address of the Wireless access point.

IMO the question of WEP is not whether you fell you may be targeted, but using WEP makes you a target. While it stops your non-technical neighbours stealing your broadband, its an invitation for any beadroom bound teenage geeks to mess with your network.

You may be able to do that, but our argument is similar to one that says, my car has poor locks, anyone can break into it in 30 seconds - in fact only an experienced car theif can do that, and unless is it is 'nick to order' (ie targeted) the casual thief will look elsewhere - the car that is unlocked. So if you have some protection, a casual hacker will look for an
unprotected network. However I wouldn't suggest using WEP on its own in a University Hall filled with Computer Science students - but that is part of the risk assessment.

You should remember that WEP is oly a confidentiality mechanism - dodes not explicitly provide authentication so hat should be added as an extra to prevent someone who does break the encryption from getting into an internal network and also using a WAN connection - although the ease of providing the protection to the WAN (internet) depends on the configuration of the router. Some routers can also be configured so that only specific computers can access he internal LAN.

If someone does crack he WEP encryption, they wll be able to eavedrop - but sensitie traffic, such as online banking is further protected by SSL. E mail may be vul1nerable if it is not encrypted by some other mechanism, but if ou are sending anything sensitive by emal, you shouldn't be using WEP, or possibly even wireless, at all.

That is not to be complacent - if WPA is available, use it, if it isn't WEP is better than nothing, bt ou should be aware f the risks and take additional steps to mitigate them if you feel it is necessary. Such steps might include frequent key changes, setting up a VPN and applying some of the other techniques such as tying MAC addresses to specific fxed IP addresses, disabling or liming DHCP scopes (so f smeone does get in, they can't get an IP address) or some other form of end to end encryption applied outside the WEP mechanism.