Frederick's Timelog

December 21, 2012August 2, 2013

When you run a Twitter trivia contest…

… I expect the answers to be right.

Namecheap, a domain registrar and web services provider, is currently running a Twitter contest with tech/domain/company trivia, awarding free domain registrations to participants, and top prizes of a Macbook Air and iPads to the top of the leaderboard. To be clear, I am not competing in this contest, and my first involvement with it was with this question. In other words, I’m not posting this because I want anything out of it—I’m posting it just to point out the mistakes.

[#115] What record does one need to edit on his/her DNS settings to speed up domain propagation?

— Namecheap.com (@Namecheap) December 21, 2012

Inconsistent tenses aside (one… his/her), the most important parts to emphasize are:

what record
domain propagation

The best answer, although not necessarily the 100% correct answer (see below), as I answered in my tweet, is the Start of Authority (SOA) record. About three other individuals on Twitter agreed with me, facing hundreds with a different answer.

In fact, the Refresh and Minimum TTL data entries in the SOA record are responsible for domain zone propagation, whether to a secondary nameserver or to the broader Internet.

Screenshot of Twitter users giving the "TTL" answer, which should be wrong. — Twitter users giving the “TTL” answer, which should be wrong.

Hundreds of others poured in their answers, most lending their support to the answer that Namecheap ultimately declared correct: Time to Live (TTL).

This is (mostly) wrong. For two reasons:

TTL is not a DNS record. It is a setting within the SOA record, and an attribute attached to other records such as A and AAAA host records. Given the question, this should disqualify it as a potential answer.
TTL whenever applied to non-SOA records affects particular records, not domain propagation (e.g. the lifetime of the ‘www.namecheap.com’ A record, not of all entries in ‘namecheap.com’).

Ultimately, the question posed was a bad one. The traditional understanding of the SOA minimum TTL is that it is the shortest frequency with which other nameservers will check against the authoritative/primary nameserver—at least according to this DNS service provider. While the original specification, RFC 1912, would completely agree with me here in declaring…

Minimum: The default TTL … This is by far the most important timer. Set this as large as is comfortable given how often you update your nameserver.

RFC 2308 changed things so that the minimum TTL in the SOA record affects only negative caching: e.g. you visit ‘doesntexist.namecheap.com’, it doesn’t work, the ISP’s nameserver caches it, and the minimum TTL specifies how long before your ISP’s nameserver fetches that data again. It’s not supposed to be used as a lower bound for update frequency anymore.

That having been said, given the constraints of record and domain propagation, we can be certain that TTL on individual resource records is an incorrect answer that was erroneously, but not maliciously, accepted.

</rant>

November 30, 2012January 26, 2017

Lowering the bar on education isn’t the answer

The following article was initially drafted with a guest author, Kirill Peretoltchine, at the end of July 2012.

A giant statue in the opening ceremony of the Athens Summer Olympics in 2004, onto which laser images of geometrical shapes and scientific concepts were projected, was a powerful reminder of a bygone era. Ancient Greece was a birthplace of logical thought, education, mathematics, science… and democracy.

The Renaissance was marked by an explosion in the diffusion of ideas, and the naissance of the scientific method that has allowed us to explore this world. This was the time of Copernicus, Galileo, Michelangelo, and da Vinci — the last of which, far from being just a scientist and artist, was also an engineer and writer: the stunning definition of a Renaissance man.

And one of the founding fathers of the United States of America, Benjamin Franklin — also the founder of our alma mater — was a polymath himself. Politician, scientist, writer…

There is a reason we honour and respect figures like da Vinci and Franklin, even if we, enlightened with 21st century practicality, do not expect to educate the entire populace in their image.

Both of us were shocked to read a real proposal by an educator at the City University of New York for the lowering of educational standards and the removal of mathematics from standard curricula.

We agree that there are serious deficits in the North American educational system that are in need of redress. We also concur that it is impractical to teach higher math effectively to every high school and college or university student. But we are firm in our belief that lowering the bar isn’t the answer. Andrew Hacker has a limited view of mathematics that fails to appreciate its value, and his solution of removing math from standards is flawed.

Continue reading “Lowering the bar on education isn’t the answer”

October 3, 2012August 2, 2013

Shameless plug for Penn

August 5, 2012August 2, 2013

Incoming college freshmen: Campus Backup Service is a ripoff

If you’re a freshman at Penn or many of the other universities that are raking in revenue from freshmen beyond tuition and fees, you may have received e-mails and letters offering all sorts of wonderful things. The one that caught my attention was something called “Campus Backup Service”.

It’s a cleverly marketed service that tries to leverage the anxiety of freshmen and parents to sell you something you don’t need — or rather, something you need, but not from this company.

There’s a disaster scenario — a student without backup suffers a virus infection on her laptop and… “her sleep, her composure, and her GPA all suffered… it was horrible”. There’s an alternate scenario — someone uses this company’s service, and avoids the disaster.

Yes, college students need a convenient and viable form of backup, just as all computer users do, but not from this company. This is almost a scam (but not quite). (Notice how they target “parents of incoming students”, who might be less tech-savvy than college students?)

Vinay Dinesh and I are both Information Technology Advisor Managers (ITA Managers, for short) at the University of Pennsylvania, and we are writing, as individuals, to help you find the right backup solution, whether it’s as simple as copying files to an external hard drive, or syncing files to the cloud. But Campus Backup Service isn’t right. (See our upcoming collaborative post to see how you can back up your files the right way.)

Continue reading “Incoming college freshmen: Campus Backup Service is a ripoff”

July 23, 2012August 2, 2013

Rebuttal to “Why I don’t want to go to med school”

My friend just started a blog. This is one of its inaugural posts: Why I don’t want to go to med school.

I respect the majority of this article. I agree with most of it — the North American medical education system is clunky, and a ton of hurdles are thrown in the way of students who want to become doctors.

Read my rebuttal after the jump.

July 21, 2012August 2, 2013