Other people's URL shorteners are the absolute evil. Your own is better.

[Man]

What is a URL shortener? It is essentially a link encoder that hides the true address of a resource from the recipient. Who needs to mask their links and hide the true address? It is clear to whom: scammers, attackers and companies whose URL does not fit on a business card.

Recently, many cloud services have directly integrated link shorteners: for example, Google Maps, Microsoft OneDrive give links to 1drv.msand goo.glwith a short token. Previously, some shorteners issued a token of 5-6 characters, but then they realized their mistake. The problem is that the space of such tokens is so small that it can be scanned by brute force (see the work of Martin Georgiev and Vitaly Shmatikov from Cornell University of Technology, arXiv:1604.02734v1). But five characters are only 62 5 options, and six characters are 62 6, which is also not very many (56.8 billion). That secret link is no longer a secret.

That's not the only reason why you should avoid other people's abbreviations.
First, a few words about the myths that people believe in. This false information encourages some users to use abbreviations.

Myths about shorteners​

The myth of saving characters in tweets​

One of the oldest myths. In fact, by using an external shortener, you are doing completely unnecessary and unneeded work. Nowadays, all platforms automatically shorten all links, see Twitter and LinkedIn help.

Thus, the platforms threaten their security and users, but that is another matter. In any case, it is better not to publish anything in the public domain. But if you are still forced to perform some actions on social networks, then an external link shortener is definitely not necessary.

The Myth of Analytics​

Some link shorteners offer users rich analytics on the number of clicks and other statistics. But there is nothing there that you could not get yourself using free open source analytics services on your hosting, as well as social network data. The social network itself will tell you how many times the link was clicked and what its CTR is.

If you are running a business on a social network and really want to get more advanced analytics, then it is better to use UTM (Urchin Tracking Modules) tracking modules, and not link shorteners:

Problems of shorteners​

Zero privacy​

You have no way to control someone else's shortener. Some of them behave in a not entirely correct way. For example, they install a tracking cookie on your device to track your actions on the Internet. This is normal practice, so do Google, Facebook and other sites that earn money on personalized ad targeting. To effectively target ads, they need to collect a detailed dossier on each person.

Zero sense​

A shortened URL is a meaningless string of characters that is almost impossible to remember. It says nothing about the real address, the name of the site, or the page it links to. And it is unlikely to be entered manually, from memory, or dictated over the phone.

Broken links​

If a shortener fails, your links become unavailable. If you only used one shortener for all your links, they all fail at once!

Think this will never happen? Take a look at the list of dead shorteners!

Your own shortener​

So it is better to avoid third-party services, and if necessary, write your own shortener and run it on your server. For example, it took the famous programmer and evangelist Grigory Bakunov 40 minutes. Grigory later gave the project to Yandex.

Running a shortener is really easy. It can be configured even in the cloud. For example, an instance in S3 can work as a redirect engine. Or any other hosting. Just create an object with a redirect to the target URL for each short URL, that's all. If you need analytics, you will have to try, but there is nothing complicated in the basic functionality.

All your long links can be processed with your own shortener. Although this does not eliminate some problems with the loss of meaning, but there are much fewer security threats than with an external shortener. That is, your own shortener is simply the lesser evil.

One way or another, but link shorteners in general are an extra level of abstraction, an increase in the attack surface: interception and substitution of links, phishing, tracking cookies, unpredictable URL.

Although any disadvantages can be turned into advantages. For example, a shortener allows you to change the URL for NSFW links to pass them on to a friend in a chat. There is a shortener for rebranding. Someone likes jokes and gags. There are not shorteners, but link extenders. And if you launch your own service, the space of possible jokes expands by an order of magnitude. Some people are ready to do a lot for the sake of "lulz" - that's "the whole point".

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