Why are URL shorteners blocked by some content filters, websites, and wifi providers?

Today I was interested to learn Flickr prohibits the use of some URL shortened links, including tinyurl and bit.ly.

This was surprising as well as annoying, since some complicated web links do not display properly in Flickr's description area when they are inserted with basic HTML link code. That makes a URL shortening service quite handy. Generally I use either bit.ly or tinyurl, and I didn't spend more time this morning looking for a URL shortening service which DOES work with Flickr currently. If you know of one, please let me know via a comment here.

I learned over a year ago that the content filters employed by many school districts block URL shorteners. This is a real pain if you're accessing Twitter, since TONS of links there are shared via shortened URLs. It's also a pain if you use URL shorteners in email messages sent to educators on school networks. Long URLs are sometimes truncated by certain email clients, or cut off / broken by email programs which insert line breaks. This frequently happens when email messages are forwarded on repeatedly. One way to workaround this problem is to use a shorter web address created with a URL shortener. If that web shortener service is blocked in the school, however, that link is also rendered useless unless the recipient knows to use a free service like untiny or unshorten.

Are URL shortening websites evil? Do they deserve the bad rap they apparently have, and are school content filtering czars justified in including these websites on blacklists, to protect thousands of educators from the distracting horrors of Twitter reading? (sarcasm here)

In his April 2009 post, "Why URL shorteners suck," Cory Doctorow identifies several common criticisms of these sites: They are sometimes used by spammers to redirect people to harmful websites distributing malware, and they cause additional web server demands via additional DNS lookups. The sites themselves may also go away in time, rending the originally shared links broken.

The current English WikiPedia article for URL shortening also includes some insights about why some folks regard the sites as bannable under its "Criticism" category. In addition to the problems Doctorow highlights (including linkrot and rickrolling, terms I had not encountered previously) it also cites privacy concerns:

[when using URL shorteners] Users may be exposed to privacy issues in that the link shortening service is in a position to track a user's behaviour across many domains

Personally, I think URL shorteners are GREAT and provide a vital communications service in a world filled with 140 character messages. I never save a shortened URL on my Diigo or Delicious accounts, I save the full URLs. I use shortened URLs every day to share links on Twitter, Facebook, Plurk and Loopt, however, and would be severely limited in my ability to share hyperlinks during the day if URL shortener services were unavailable.

Are URL shortened websites blocked by the content filter at your school? Please take a moment to respond to the PollEverywhere web survey below and indicate your response.

(Poll results are available here.)

Personally I agree with one of the commenters to Doctorow's post, who observed, "Saying tinyurl.com is 'bad' for you is like saying chocolate is bad for you." While some people may abuse URL shorteners may be abused by some individuals and groups, there are also lots of legitimate and constructive uses for these sites. The fact that some people use these sites for malicious purposes should not mean the sites get blocked for EVERYONE by a locally designated digital censor.

Open access should be provided to URL shortened websites in our schools. If clicking on a shortened URL leads you to a bad place, then the source where you clicked that link shouldn't be visited/trusted in the future. That's a choice best left up to individuals, however, and not made by a school content filtering czar.

Technorati Tags:
content, education, filter, network, protect, school, shortener, spam, url, tinyurl, bitly, malware, justify

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