It's time to question some security assumptions. Regular users' systems are always on an internal network with a firewall between them and the Internet. The only hosts reachable from the outside are a few bastion hosts. Bastion hosts run a strictly limited set of software, and only sysadmins have accounts on them. Computer security depends on physical security, because anyone who breaks into the server room can boot the server from a rescue disk and have his or her way with the files.

Meanwhile, in the real world, you have a copy of the project you're working on and a bunch of confidential e-mail on your laptop, and you're drinking La Minita at Dana Street Roasting Company while you peruse your project's Request Tracker and hold a Jabber meeting with people in three countries.

Public wireless cafés are a lot of great things, but secure corporate networks they're not. Because more and more companies would rather pay for laptops and drop-in office space than cubicles and desktops for all, you can wave bye-bye to the neat security chart with a bunch of stuff between the user and the menacing Internet Cloud.

Linux distributions are starting to offer good support for some encrypted partitions, which do the attacker no good without the key. Mike Petullo takes the process to its logical extreme and encrypts the root filesystem, which means you can encrypt everything (page 62).

The less we trust the network, the more we need encrypted e-mail. At Linux Journal, we rolled out GNU Privacy Guard (GPG) for everyone. Encrypted mail isn't the tweaky mess it used to be, now that the common mailers are integrating GPG support. Find out how to make secure mail a part of your work life in Roy Hoobler's article on page 52.

Now that everyone is outside all the time, the problem of removing unneeded software and keeping packages up to date is even more critical. Fortunately, many of the Linux distributions offer easy tools for installing new versions. Jeremy Turner shows off some screenshots on page 46. Meanwhile, we're still experimenting with SELinux, which could lock down even insecure versions of software to contain attacks. James Morris gives us a peek at the SELinux future on page 56.

The new mobile way of working isn't only a burden for sysadmins. Users often prefer to escape from cubicle-land. Why not make your company's Linux migration a productivity and multimedia treat, not a retraining chore? Just as Lincoln Durey's “Dear Laptop Vendor” was going to press in the fall of 2004, HP made the bold move of offering Linux preinstalled on a full-featured notebook computer. We had one at Linux Journal to try out, and yes, we're impressed. Get the details, including the results of a support call, on page 74.

Have fun keeping your systems secure for the real world, and if you see me editing the next issue at a coffeehouse, come over and say hi.