One of the major decisions to be made when creating a website or web application is the structure for the website's URLs. Once a URL is established, it becomes associated with links on external websites, bookmarks, and search engine indexes. Pages should not be moved or deleted because they would otherwise become 404 pages to anyone following one of those links or bookmarks. Thus, when I chose the URL structure for this website and designed the backend, I had to try to do so with foresight: no matter what I decide to add or change about the website after two, five, or eight years, I'll have to accomodate the original URL structure in order to avoid breaking links.

Ideally, links would never be broken, and as soon as a page is added to a website, its URL would be permanent. Anyone who bookmarks or links to the page elsewhere relies on the idea that the page will always be available. Unfortunately, this can never be guaranteed. Several months ago, Jeremy Keith wrote about the problem of "linkrot"—no matter where online data is hosted (and even though the Internet Archive provides some protection), the data will eventually disappear, and if it doesn't disappear, the domain name it relies on will expire. Until I somehow lose the ability to preserve this website, though, I'll combat linkrot with my Ten-Year Promise: until the year 2020, all URLs on this website will be permanent.

Although I can't foresee what will happen to the site between now and 2020, I'll do my best to make sure pages are preserved. If something has to be moved, I will set up automatic HTTP redirects so that old URLs still work. If for some reason I have to remove a certain page (such as for legal or personal reasons), I'll leave a note at the original URL.

I don't know what I'll do once we get to 2020. But, even though the web is (in the most general sense possible) about the same as it was twenty years ago, I have a feeling that by 2020 it's going to be something completely different than the web we know today, and this whole idea will need to be rethought altogether. Nevertheless, I'll preserve URLs as long as I can after that, and if I can't, I'll try to set up some sort of archive that links old URLs to saved pages.

Another issue is created by the shortened links used in Twitter and social media. I doubt that, in a few years, people will regularly be looking through social media archives more than one to two years old, so broken links in ancient Twitter archives won't be much of a problem. Still, people do sometimes use shortened links in other places as they would use normal links. I don't want to rely on services like bit.ly (not all of which are quite as reliable as bit.ly) to maintain links indefinitely. Hence I've joined the "personal URL shortener" bandwagon. All links to blog entries—and, in the future, other pages on this site—have their own short URLs based at the domain iotb.in. As long as I have the ability to own a foreign domain, I'll maintain links there, too. In the future, this will also provide interesting opportunities to experiment with other linking strategies, set up archives, and even deal with re-used URLs on the main site.