Posts Tagged ‘security’

SSH Without a Password

You can ssh from one box to another without typing in your password. This is done using a key pair. One key sits on the computer A, the other on computer B. Starting logged into computer A, here’s how you do it:

ssh-keygen -t dsa
ssh B mkdir ~/.ssh/
cat .ssh/id_dsa.pub | ssh B 'cat >> .ssh/authorized_keys'

When you run ssh-keygen, do not use a passphrase, just press enter. Also, change the bold B to the name or IP of computer B. If you were successful, you should be able to `ssh B` without a password.

To repeat for another computer, do not repeat ssh-keygen, just repeat line 2 & 3. If you run ssh-keygen again, your key will be overwritten and you’ll need to copy it again via line 3.

Using keys is an excellent security measure. You can even setup sshd to only allow keyed logins. No passwords allowed. If you do set this up, make sure you have physical access or a rescue/remote console or you’ll be locked out if you lose your key.

WiFi Security

A lot of people have WiFi, or a wireless network. Sadly, many of the WiFi networks are completely open and anyone can log onto the internet and a home network without a password. This is a big security risk. There are plenty of options available, and you won’t have to buy anything extra.

The most common security for wireless routers is WEP security. This requires a 6 or 13 character password to access the wireless network. Without the password, you won’t be able to access it at all.

Almost every router has a web page built in that you can use to change the settings. To get to it, first you have to know the network address of the router; this is always the gateway address of any computer connected to the router. You can find it by click on Start->Run, then type ‘cmd’ and click OK. This should bring up what looks like a DOS box or command prompt. Type ‘ipconfig’ and press enter. Just type the ‘Default Gateway’ address into your web browser.

You should have a login page, if not, please leave a comment with the make & model of router and I’ll see what I can dig up about your router. If you’ve never ever seen this page before, then the factory password is probably still in place. Most of the time the username is ‘admin’ and the password is either ‘default’, ‘admin’, or should be left blank. Again, if none of these work, leave me a comment and I’ll look it up for you.

Once you are logged into the router, there should be a link labeled wireless, security, or setup; Click it. You should see a drop down box with WEP in it. Select WEP. You may have to save settings before you can enter a password, and if this is the case, make sure you are on a hard wired computer, not a wireless one. Make sure you choose 128-bit, not 64-bit which is inferior. Setup your password and save the changes.

You should be all set up. If none of these directions work, please leave a comment or google your make & model router for information on how to set it up. Most sites list step-by-step instructions.

Once you are secured, you won’t have people hoping on your network. Please note that this doesn’t mean that you wireless network is completely secure because everytime there’s new security, hundreds of people try to break it and many succeed.

If you live out in the country with no one around for 200 yards, you are safe enough to run the wireless without any security, but I advise you to set it up anyways, because you never know.