Dynamic Links" (although existing goo.gl links will continue to function). Advantages The main advantage of a short link is its brevity. Depending on the transcription used, it might be more easily communicated and entered without error. To some extent it can obscure the destination of the URL; this may be advantageous, disadvantageous, or irrelevant. Shortcomings Short URLs often circumvent the intended use of top-level domains for indicating the country of origin; domain registration in many countries requires proof of physical presence within that country, although a redirected URL has no such guarantee. Abuse URL shortening may be utilized by spammers or for illicit internet activities. As a result, many have been removed from online registries or shut down by web hosts or internet service providers. According to Tonic Corporation, the registry for .to domains, it is "very serious about keeping domains spam free" and may remove URL shortening services from their registry if the service is abused. In addition, "u.nu" made the following announcement upon closing operations: The last straw came on September 3, 2010, when the server was disconnected without notice by our hosting provider in response to reports of a number of links to child pornography sites. The disconnection of the server caused us serious problems, and to be honest, the level and nature of the abuse has become quite demoralizing. Given the choice between spending time and money to find a different home, or just giving up, the latter won out. Google's url-shortener discussion group has frequently included messages from frustrated users reporting that specific shortened URLs have been disabled after they were reported as spam. A study in May 2012 showed that 61% of URL shorteners had shut down (614 of 1002). The most common cause cited was abuse by spammers. Linkrot The convenience offered by URL shortening also introduces potential problems, which have led to criticism of the use of these services. Short URLs, for example, will be subject to linkrot if the shortening service stops working; all URLs related to the service will become broken. It is a legitimate concern that many existing URL shortening services may not have a sustainable business model in the long term. In late 2009, the Internet Archive started the "301 Works" projects, together with twenty collaborating companies (initially), whose short URLs will be preserved by the project. Transnational law Shortened internet links typically use ccTLD domains, and are