Month: March 2011

Awake at 4:30am PST

Can’t sleep! My sleep schedule is off and there’s been alot on my mind lately. Hopefully doing a mind-dump on this blog will help me sleep!

On My Mind:

  • Still working on: Ruby on Rails, Python, Javascript/JQuery/AJAX, Android and iPhone development,
  • Graduate school + jobs
  • Extensor muscles
  • Should i join a gym to busy myself more? How about P90x???
  • Summer internship at Cisco in San Jose!
  • Playing around on StackOverflow and Quora
  • Where i’ll be in the year 2016

Also, to further my writing, interview, and algorithm skills, i will be writing entries as i discover and rediscover them. Some of these entries may be password protected so you’ll need to find my email at my other site if you want access to them!

Explaining Asymmetric Cryptography via Scissors, Wrapping Paper, and Presents

Asymmetric Cryptography and its variants have always been difficult for an average user to understand. This barrier has led to security mistakes on the user’s behalf, resulting in compromised data, etc.

In this entry, I’m going to take a stab to simplify asymmetric cryptography, aka public-key cryptography, using a simple metaphor:


In a magical town where it’s Christmas all year long, the citizens of this town all have their unique scissors, wrapping paper, and ribbons for tying bows. What makes this world unique is that only a citizen’s scissors can cut his own wrapping paper, not others!

In the central part of this world, there’s a universal store where everyone’s individual wrapping papers are available for others in case they want to deliver a present.

Specifically, Bob has a present for Sally. Bob enters the universal store to find Sally’s wrapping paper; once he returns home, he wraps his present for her using her wrapping paper. Once done, Bob ties his ribbon into a unique bow on the present and delivers the present to Sally!

However, nosy Dan is curious to see what’s inside the package, so he tries to use his scissors to cut through the wrapping paper! Yet he fails…

Eventually, Sally receives the present, recognizes Bob’s ribbon style, and cuts off the wrapping paper with her pair of scissors to find a shiny, gold trumpet!

Now that the story is out of the way, let me explain the story and each item:

  1. In the story, every individual has their own wrapping paper, scissor, and ribbon for a bow; moreover, only their scissor can cut their own wrapping paper! They can’t go around cutting other people’s wrapping paper. The wrapping paper represents the public key, the scissor represents the private key, and the ribbon for the bow represents the individual’s digital signature.
  2. Bob enters the universal store, essentially a server that contains people’s wrapping paper–the public keys– and wraps the present in it (encryption)! After Bob wraps the present using Sally’s public key, he ties a bow to indicate that the present came from him. Otherwise, nosy Dan could have wrapped a present using Sally’s wrapping paper himself and pretend it was from Bob.
  3. When Sally receives the present from Bob, only her scissor (the private key) can decrypt the contents of the message! Plus, the bow on the present confirms that it was from Bob!
  4. As mentioned, the purpose of the bow is to act as a digital signature. If nosy Dan did manage to unwrap Bob’s present for Sally, he would not be able to tie the bow the same way Bob did! If nosy Dan just tied the bow however and sent it to Sally, she would know her present was tampered with!

The end. Asymmetric cryptography simplified.

Technology in Disaster Zones

Eleven years into the 21st Century, we have seen some of the most horrific natural disasters strike, from the Indian Ocean Tsunami to Hurrican Katrina to other disasters in Haiti, China, Pakistan and the recent incident in Japan. Over the course of these eleven years, warning systems have been implemented, such as the recent earthquake near Japan (however, the warning system gave Japanese residents in the northern region only 15 minutes to move to higher ground). Analyzing these events and the technologies deployed can help other cities prepare, especially in the West Coast where San Francisco, Los Angeles, or Seattle built on fault lines.

Giants

Once a disaster strikes, the goal is to brace for impact, begin search and rescue, and eventually rebuild. The first thing that the international community does is raise money for donation. Others take an extra step to contribute more. In particular, I’m thinking about technology giants such as Google, Microsoft, Twitter and the likes–they contribute skills and resources.

Specifically, the first thing these titans do is bring awareness to the situation, such as having donation links or highlights on their home page. Microsoft set up a page on its Bing search engine, Google inserted a Spotlight on YouTube’s homepage, and many, many more.




One of the most impressive feats is Google working with GeoEye to make satellite-imagery available to Google Earth; these titans have also created a Crisis Response Team to coordinate other logistics. For Japan’s disaster, Google put together an online person-finder data base in several languages for people seeking or providing information for those in need. Microsoft is currently assisting by offering free technical support and temporary software licenses. Apple stores in Japan remained open to let everyone keep in touch with the news on tv or use the Macs to update family members and friend.

 

Twitter is also pitching in by organizing the flood of information to update people around the world and those affected. This is by-far an easy way to centralize the flow of updates and information. From a personal experience, I was snowed in during one of the largest snow storms in Europe in Dec 2010. There were thousands upon thousands of stranded customers trying to talk to airline representatives for help, etc. but the Twitter feed they set up provided invaluable information and updates that couldn’t be reached elsewhere.

Technology for Developing Regions
From my experience and exposure in Information, Communication, and Technology for Development (aka ICT4D or ICTD), I see a parallel where technology for developing regions can translate over to disaster zones. Education and the like might not matter too much, but healthcare, energy, and communication will become critical.

CommCare, by Tapan Parikh (a professor at UC Berkeley’s School of Information), is about mobile information tools for Community Health Workers. Using cell phones would be a great way to utilize the flow of communication; however, i would try to limit this to internet access, text messaging, or using geo-location if available. Full-fledge phone calls have higher overhead and we don’t even know whether the infrastructure is still standing. For Haiti, T-Mobile USA waived charges for international calls to Haiti and T-Mobile customers within Haiti were allowed to roam on T-Mobile’s partner networks.

This also reminds me of PCS’s $40 cell phones and whether inexpensive cell phones could be deployed to people affected by a disaster. This also extends my thoughts to deploying One Laptop Per Child (OLPC) minus the educational aspect. OLPC was designed to be rugged and reliable, recharge using solar energy, and can be tweaked for communication purposes at established sites.

We Care Solar produces Solar Suitcase which provides energy. This neat equipment is essentially a solar electric system which powers overhead LED lighting, charges cell phones or two-way radios, and includes LED headlamps that come with rechargeable batteries. This was actually deployed to Haiti.

Military Assistance
By far, the military is practically a backbone in any disaster relief mission. They have the equipment, heavy duty transportation planes, the man power, and even a Carrier to deploy tons of aid. When China had their 7.1 earthquake in 2008, the People’s Liberation Army (PLA) and Armed Police Force (APF) deployed roughly 6,400 troops to the region. For Haiti, the US Southern Command sent the USS Kearsarge to Haiti. The USS Keasarge is an amphibious ship that carries helicopters, Sikorsky-built CH-53s, and MH-60 helicopters to provide logistical and humanitarian support. Overall, the pilots delivered 1,500 gallons of water and 350 metric tons of prepackaged food, hygeine kits, etc.

Recently, the dual-use of military technologies and equipment is catching attention. Northrop Grumman, a defense contractor, has a multifunction radio for opertions requiring high security and high performance military tactical networks to connect air, land, and sea forces. It can even be used to communicate with civilian first-responders and establish relief centers. The Defense Advanced Research Projects Agency (DARPA) has a project that connects electrodes to detect brain activity; this could be used to find survivors under rubbles.

Work Cited

  • http://executiveeducation.wharton.upenn.edu/wharton-aerospace-defense-report/upload/Military-Hardware-in-Disaster-Relief.pdf
  • http://www.eweek.com/c/a/Search-Engines/Google-Microsoft-Other-Tech-Companies-Pledge-Support-For-Haiti-531991/
  • http://www.eweek.com/c/a/IT-Infrastructure/Intel-HP-AMD-Other-IT-Vendors-Continue-to-Give-Haiti-Aid-391402/
  • http://wecaresolar.com/index.html
  • http://www.peopleforum.cn/viewthread.php?tid=14709
  • http://kevinrose.com/blogg/2011/3/14/apples-role-in-japan-during-the-tohoku-earthquake.html

Comments: Cool for Some, Not for Others

I made some observations about why commenting is cool for some and not others:

Observations

  1. Commenting is great when there’s a specific question to give the crowd a push, such as Quora and StackOverflow (SO); Those two are driven mostly by specific questions, while news outlets will post a 5 to 10 paragraph article of informative news and that’s it. Comments in the news sites are all blurbs and rants and the quality feels low or at least uncertain; for Quora and SO, there’s a sense of legitimacy, ie. the top comment in the page is from a guy with 20 yrs experience. While going over comments in the news sites, i sometimes wonder if i’m dealing with a misinformed housemom in the mid-West and don’t even bother rebuking her.
  2. In Quora and StackOverflow, we see the comments immediately to hook in users.
  3. All sites practically use some sort of ranking system to boost some comments up.
  4. In my opinion, commenting is cool on sites like Facebook, Quora, and StackOverflow because there’s a sense of comradery. Also, you know your comment will be seen or make an impact bc of the small community, or even a “community within a community.” What i mean by this is, for example, something like my fraternity. I’m in a house with about 35 other guys, but i’m close to about 5 guys. The point is that current news sites sometimes make u feel like your 2 cents won’t matter or be seen at all, whereas Quora and SO does. Think of Facebook’s model when friends comment on a picture or status: it’s just a handful of ppl who all know each other and they can all talk to each other. I don’t know if this is something worth more consideration later btw.
Screenshot of Quora

For Quora, it builds that model too when you and your friends with same interests scan the same topics, but i feel this isn’t as big (maybe i’m not an active, long-term user); i felt more of the comradery in Quora and StackOverflow–ppl with the same interest that you can EASILY trust.

The other thing i noticed is that on Quora, i navigated to questions i knew i could answer or questions that peaked my curiosity. The sense of being able to gain by CONTRIBUTING or LEARNING was what kept me poking around.

Focusing on StackOverflow, there’s an abundance of analysis, the most recent from Professor Bjoern Hartmann’s research Design Lessons from the Fastest Q&A Site in the West

Excerpt:

Q&A On Other Sites Is Often Not About Factual Knowledge
Several distinct types of questions on Q&A sites can be distinguished:  factual (seeking objective data);  advice, (seeking recommendations);  opinion, (seeking others’ viewpoints), and  non-questions  (spam) [11,15,21]. Significant parts of general Q&A sites are  conversational; the sites perform poorly on focused technical questions [21]. Algorithms to distinguish between informational and conversational threads have been proposed [11,25]. We do not investigate such distinctions as SO explicitly (and successfully) discourages conversational contributions.
Sites Leverage Both Intrinsic and Extrinsic Motivations
Motivations of individuals who contribute answers to Q&A sites can be categorized as either intrinsic (altruism, the desire to learn) or extrinsic (gaining status, monetary rewards) [14,21,23]. Point systems and other game mechanics are frequently used extrinsic motivators. Adding monetary rewards can transform the user’s sense of the system from a social interaction space to a more formal transaction space [14]. Stack  Overflow has several highly