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Featured Articles           This month (September 2011), UCF officially killed the “UCF” SSID to be replaced by “UCF_WPA” and “UCF_WPA2.” Configuring Ubuntu Linux to connect to the UCF WPA2 network is neither trivial nor documented by UCF. To aid other UCF Ubuntu users, I created a Wireless article on the unofficial UCF wiki. This includes links to the official UCF certificates and instructions on how to connect to the UCF_WPA2 network in Ubuntu. While I frustratingly waited to connect to the UCF Wifi after a recent change to their system, I typed up the following email complaint to the UCF DoIT Manager. If *you* have also had issues with unstable/dropped connections, slow bandwidth, latency, or the inability to connect to the UCF Wifi, I urge you to also contact the UCF Department of Information Technology via: cst@ucf.edu = General bob.yanckello@ucf.edu = Bob Yanckello (UCF Chief Technology Officer) lou.garcia@ucf.edu = Lou Garcia (UCF Network Manager [responsible for wireless services]) chrisv@mail.ucf.edu = Chris Vakhordjian (Information Security Office) tim.larson@ucf.edu = Tim Larson (ERP Consultant) jim.ennis@ucf.edu = Jim Ennis (Enterprise Systems & Operations) andy.hulsey@ucf.edu = Andy Hulsey (Telecommunications [includes Network Services]) aaron.streimish@ucf.edu = Aaron Streimish (Project Performance & Management Office) Email below While I understand the benefit of encrypted wireless communications, UCF’s decision to require all student wireless clients to use WPA without preparing to sufficiently upgrade the wireless infrastructure has rendered the UCF Wifi *unusable*. Allow me to provide a brief log of my Internet Experience this afternoon (2011-09-15). 12:02 – attempt to connect to WiFi – fail for 9 minutes 12:11 – connected 12:11 – google ’email ucf department of information technology’ 12:12 – disconnected For my Discrete Mathematics II course at UCF (COT4210), I had to do some implementation with Finite State Machines. My favorite of our tasks (though the most difficult) was to convert a Regular Expression (RE) to an equivalent Deterministic Finite Automata (DFA). And since our professor let us use any language, I tried to branch out from Java & C (which are annoyingly overused in Academia). I decided to teach myself Python. And it turns out, it was a good choice too–considering it’s wonderful built-in functionality for Lists, and the heart of this program is a huge 2D array defining the automata’s transition function. Also, I miss scripting languages–especially when I’m writing a program as a learning experiment as opposed to trying to make it as efficient as possible. So, without further Ado: here’s my code. It reads a RE in postfix notation from input.txt. Two cautions about postfix REs: You must explicitly state concatenation The Kleen Star is already a postfix operator in REs, so it doesn’t really work to use a mathematical infix2postfix library, as it treats the kleen star like an infix multiplicative operator. I treat it as an operand and throw it directly into the I’m going on another cross-country cycling trip this summer, and I’m in the market for a good, solid MP3 player. Disclaimer: I’m a software guy who likes my devices to be good quality and long lasting. I’m by no means an audiophile, hardware tech, or professional MP3 player reviewer. All of my research was done using Google, and the only MP3 player I’ve owned is the Sansa e260 v2. Requirements Note: These are my personal requirements. They effectively eliminated a *lot* of products in the MP3 market. 1. Rockbox Support First and foremost, I need rockbox support. Rockbox is a must-have FOSS firmware for MP3 players with a fantastic feature list. You can buy an MP3 player with terrific hardware design, but your experience can be absolutely ruined by poorly designed firmware. My old Sansa e260 was this way, but once I installed rockbox, it was like the device was freed from a software prison. And, of course–another benefit of it being open source–you can completely customize the look+feel of your MP3 player with other user’s custom rockbox themes. Here is a list of MP3 players (targets) and their support status for the Rockbox firmware. 2. Rugged Components that In a given week, I touch maybe a half dozen different Operating Systems/Distributions. Some are similar to others (centos, rhel), some–not so much (solaris). The common commands are easy enough to remember ( @ls@ vs @dir@ ), but I always forget how to search through each OS’s package manager for a software package. For my reference (and perhaps yours?) here’s a list for each of the OSs’ package managers I use frequently: yum – RHEL/CentOS yum list apt – Debian/Ubuntu apt-cache search pacman – Arch pacman –sync –search pacman -Ss portage – Gentoo emerge –search # pkg names only emerge –searchdesc # pkg names & descriptions emerge -S # alias of –searchdesc See Also: “Install ‘build-essential’ on RHEL/CentOS and OpenSolaris”:/wp/?p=231 This blog has been down for a few months while my servers were physically being moved. However, I finally purchased VPS hosting, and downtime should no longer be an issue! To celebrate, I’m going to provide my Google Alphabet as filler for this post (an interesting experiment I saw here http://www.rosshuggett.com/2010/12/my-google-alphabet.html) a is for aol b is for bank of america c is for craigslist d is for dictionary e is for ebay f is for facebook g is for gmail h is for hotmail i is for ikea j is for jetblue k is for kmart l is for lowes m is for mapquest n is for netflix o is for orlando sentinel p is for publix q is for quotes r is for rate my professor s is for southwest airlines t is for target u is for ucf v is for valencia community college w is for walmart x is for xl 106.7 y is for youtube z is for zillow The list is quite curious. I disable Web History in all my Google accounts, so these suggested words are most likely regional. It’s interesting to see what others in your area are searching for, though. I came back from my “cross-country bicycle trip”:http://1guy2biketrips.michaelaltfield.net to discover I could no longer send signed email because my key expired! I’ve also changed colleges from “SPSU”:http://www.spsu.edu/ to “UCF”:http://www.ucf.edu, and my old college is expiring my email address, so here’s what I need to do: # Extend my key’s expiration another year # Add new email address to subkey # Save updates to key # Export a new public key Background Information GPG “GPG (GNU Privacy Guard)”:http://www.gnupg.org/ (used here) is a popular, cross-platform implementation of “OpenPGP (Pretty Good Privacy)”:http://en.wikipedia.org/wiki/Pretty_Good_Privacy defined in “RFC 4880”:http://tools.ietf.org/html/rfc4880. OpenPGP outlines a standard, open message format for maintaining the “confidentiality”:http://en.wikipedia.org/wiki/Information_security#Confidentiality and “integrity”:http://en.wikipedia.org/wiki/Information_security#Integrity of electronic messages. Why Subkeys? “Public Key Cryptography”:http://en.wikipedia.org/wiki/Public-key_cryptography is long, complicated, and well outside the scope of this post. However, one thing I never fully understood was the functional purpose of subkeys. Thankfully, “the GPG documentation”:http://www.gnupg.org/gph/en/manual.html is excellent. So, there’s 2 major things I want to accomplish by using GPG with my email # Confidentiality through encryption # Integrity through signatures The designers of PGP viewed the signature role as indefinitely important while the encryption role as dynamic overtime. Therefore, when we first generate a keypair, 2 keys are created: 1 primary key for 
Much to my surprise, I discovered that I have 25 registered users to this web blog. I’d like to take this opportunity to point out that I’ve since created another “blog specifically to document a ~3,000 mile bicycle trip that a friend and me are embarking on this summer (2010). The website is: 2guys1biketrip.com”:http://www.2guys1biketrip.com. Although this new blog is (obviously) _mostly_ cycling-oriented, there are some technological posts as well. For example, I plan on “plotting our trek in real-time on a Google Maps mashup using a GPS-enabled cell phone”:http://2guys1biketrip.com/wp/?page_id=59. For more info, see “my ‘GPS Tracking’ post on 2guys1bike trip”:http://2guys1biketrip.com/wp/?p=69. Also, one of the many obstacles I’m trying to dodge for this trip is “how to charge my batteries”:http://2guys1biketrip.com/wp/?p=51. I’ve considered “pedal-power”:http://blog.makezine.com/archive/2009/06/how-to_pedal-powered_phone_charger.html and solar power. To monitor our progress as we prepare for this epic trip, be sure to subscribe to our “2guys1biketrip RSS feed”:http://2guys1biketrip.com/wp/?feed=rss2. I’m sure there will be some solar panel hacking posts on 2guys1biketrip in the not-too-distant future. Also, if you’ve found any of these postings to be helpful or you just feel like being exceptionally nice, please consider “contributing to our trip”:http://2guys1biketrip.com/wp/?page_id=6. Donations of any amount will be _much_ appreciated (we are both college students, Plausibly deniable encryption is a fascinating concept. For example, “TrueCrypt”:http://www.truecrypt.org/ (a FOSS for hard disk encryption) has a wonderful “Hidden Volume”:http://www.truecrypt.org/docs/?s=hidden-volume feature that provides “Plausible Deniability”:http://www.truecrypt.org/docs/?s=plausible-deniability. The concept is: you install 2 OS instances on your computer–1 in a hidden volume. If, for whatever reason, you were forced to reveal your encrypted data, you could give access to decrypt your fake, but seemingly legitimate, OS instance. If done correctly, this could prevent you from forfeiting your sensitive data. What if you want to encrypt some data to a file, bury it on a thumbdrive somewhere, and make it appear to be just an obscure filetype (possibly corrupted)? I ran across “the answer”:http://old.nabble.com/Is-it-possible-to-decide-what-is-a-gpg-file–td26392408.html when studying for my Secure Computing final. I haven’t had a chance to research this potential solution, but there seems to exist a project that builds onto the Blowfish cypher to achieve this plausibly deniable encryption: “Blowfish Updated Re-entrant Project (BURP)”:http://www.geodyssey.com/. Exerpt from “burp.txt”:http://www.geodyssey.com/cryptography/burp.txt Unlike many similar programs, BURP writes to the output file only the ciphertext (i.e., it writes no “file headers”, password verification data, system, program or content identification strings, etc.). Consequently, such file can not be “provably” identified as ciphertext, as long as the key I’ve got a hellacious project due and finals all next week, but this was just too much fun to pass up. In any case, compiler optimization increases compile time, and anything that gives me more time to sword fight on $1000 office chairs is worth a little R&D. I’m working on writing this cut-down MIPS processor simulator for my Computer Organization class at UCF. I googled “word alignments” to help me better understand the most efficient calculations for converting the Byte Aligned Program Counter address to the Word Aligned Memory array when I ran across an interesting article showing that the mere *order* of variable declarations in a C program can affect the amount of memory used by that program. The article explained the situation very well, and it makes sense why this issue would happen, but I was surprised that the compiler wouldn’t try to optimize situations like this by re-ordering a set of concurrent variable declarations of alternating data types. In any case, I continued to hack away at my project when I began to think about whether or not gcc translates multiplication and division operations where one of the operands is a power of 2 into simple |
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