Kategori: Linux and UNIX

Learning Tree’s System and Network Security Introduction course begins with a description of the four fundamental concepts of cyber security: authentication, confidentiality, integrity, and availability. That leads into a discussion of authorization: “who is allowed to do what.” The conclusion is the “access equation”: Authentication + Authorization = Access (We also discuss situations where access is […]

I wrote a series of blog posts a while ago about SSH authentication using cryptographic keys rather than passwords. I discussed why SSH keys provide easier authentication, how to set up an SSH key agent, and how to maintain multiple websites. There are two areas of security to consider regarding SSH. I think of them […]

Isn’t Linux virus-free? By the classic meaning of ”virus”, yes. But there is malware for Linux. But Shouldn’t We Worry? What about the more traditional sense of ”virus” we worry about on Windows operating systems? What about the risk posed by hostile data hitting user platforms through e-mail, web, and removable media? To the extent […]

I kept noticing that I frequently make the error of doubling a word in what I write. When I write the source document in HTML or LaTeX, the line breaks are arbitrary. That means that the error may be obvious in the output, but not so obvious in the input. For example, the file I […]

Over the past two weeks, here, and here, I told you how to set up SSH so your remote access is both more secure and more convenient. Let’s put that to use! The Scenario Let’s say that you maintain a website, and you create and edit pages on both your office desktop computer and your […]