( 2014-11-09)


  1. “Kernel Space Definition.” The Linux Information Project 2004. Web. Link (remote) →
  2. “Kernel Definition.” The Linux Information Project 2004. Web. Link (remote) →
  3. “User Space Definition.” The Linux Information Project 2004. Web. Link (remote) →
  4. “Root Directory Definition.” The Linux Information Project 2004. Web. Link (remote) →
  5. “Home Directory Definition.” The Linux Information Project 2004. Web. Link (remote) →
  6. “Login Definition.” The Linux Information Project 2004. Web. Link (remote) →
  7. Britt, Aaron. “On Language: Avatar.” The New York Times Magazine (2008): n. pag. Web. Link (remote) →
  8. Honan, Mat. “It’s Time to Abandon Passwords.” Gizmodo Jun. 2011. Web. Link (remote) →
  9. Newman, Jared. “The Username/Password System Is Broken: Here Are Some Ideas for Fixing It.” Time (2012): n. pag. Web. Link (remote) →
  10. Norman, Donald A. “Words Matter. Talk about People: Not Customers, Not Consumers, Not Users.” interactions 13.5 (2006): 49. Web. Link (remote) →
  11. Raymond, Eric. “Userland.” The Jargon File 2014. Web. Link (remote) →
  12. Stross, Randall. “Goodbye, Passwords. You Aren’t a Good Defense.” The New York Times (2008): n. pag. Web. Link (remote) →

User login

  • A “login” is the act or procedure of “logging in” or “logging on” to a computer system
  • One “logs in” as a user
  • A user is identified and authenticated by the system using:
    1. A text user name
    2. A text password
      • There is significant pressure on the convention of text password security, today, and biometric alternatives are entering the everday consumer market (e.g., Apple’s TouchID); but in 2014 text password security remains the most common form of authentication in consumer computing
  • This information is entered by the user into a login console or window
  • The system records this information in an access log

User account

An account is a specific example of the general concept of a domain, in computing

  • Today, one “logs in” to an account assigned to oneself as a user
  • Fundamental form of your relationship with any computing device

  • Accounts in banking
    • Not a physical space set aside exclusively for your use
      • Contrast with safe deposit box
    • An abstraction or virtual space containing your assets
  • An account is defined by:
    1. A configuration of access privileges, for access to computing resources
    2. A demarcation and assignment of virtual space in memory, for the storage and manipulation of data objects: the home directory

Password security

  • Two steps:
    1. First, identify someone as a legitimate user. Identification answers the question, Who am I?
    2. Second, authenticate that user. Authentication answers the question, Are you really who you say you are?
  • Why do we need to ensure that the user is who she says she is?
    • A digital domain is a simulated, virtual environment
    • Easy to simulate or masquerade as something or someone else
  • In so far as text password authentication uses forms of written language, it comprises an important part of the linguistic history of computing
    • A use of human language for a purpose beyond the usual purpose of writing or communication
  • It’s a part of the history of computing where the linguistic and mathematical fundamentals of computing have often been pitted against each other

  • Precedents in literary history
  • From batch processing to time-sharing operating systems: one mainframe, many “dumb” terminals

  • Dictionary attacks
    • In 2012, “password” was still the most popular password!
    • Why are actual words, like “password,” bad passwords? Because you can find them in a dictionary, and you can write a program to try every word in a dictionary as a password
      • Also easy-to-remember sequences of numerals, like “12345”
  • Why care if your password is guessed and your account hacked?
    • Mischief: vandalizing of your account
    • Identity theft and other modes of fraud
  • How Secure is My Password?

  • Biometric authentication methods represent the end of an era in the linguistic history of computing, as text passwords are abandoned
  • Biometric alternatives
    • Fingerprints
    • Palm veins
    • Finger veins
    • Hand geometry
    • Eye veins
    • Iris of the eye
    • Walking gait
    • Voice print
    • Keystroke dynamics (typing patterns)

Kernel space and user space (“userland”)

  • Once you’ve been identified and authenticated, an operating system grants you access to a restricted domain defined for you
  • This user space is segregated from the operating system’s kernel space
  • The first layer of user space is the shell
    • A plain text command line interface
  • Interacting with a shell: a prompt signals readiness to accept a command

Home directory

Your home directory is user space assigned to you for file storage, but it is rarely located near or at the root of the filesystem tree

  • Filesystem root
    • “Top” (or bottom) of filesystem tree
    • In Unix, one root for the entire filesystem
    • In Windows, one root for each storage device and/or partition of a storage device
  • Filesystem tree

User profile and avatars

  • User profile: another form of user space
  • May represent you using an avatar
    • From Sanskrit avatāra
    • In Hinduism, a deity (e.g., Vishnu) incarnated on Earth
  • Second Life, 2003

The proliferation of avatar’s second meaning [in digital culture] can be traced to Second Life, a multiplayer online virtual world, where players fashion their own online personae called avatars. (Britt)

  • Other places you may find avatars
    • Blog comment threads
    • Customer service chat
    • Video games
  • 2009 film Avatar