kurz.nu is a url shortening service like tinyurl.com or bit.ly. There are two different modes 'redirect' and 'preview'. The redirect mode directly redirects to the target-url. In preview mode kurz.nu shows where the shortlink points to. The preview mode is available if at /v/ or at /preview/. While the redirect mode is at /r/.
The service is designed and operated with privacy in mind. We do not log, save, collect any ip adresses on a permanent basis. Nevertheless in order to protect our service from denial of service attacks we maintain a cache with ip addresses used this service within the last 24 hours. However after 24 hours you can be sure there is no IP information kept.
kurz.nu is operated by Florian 'scusi' Walther here are the contact details:
Florian Walther Sredzkistr. 40 10435 Berlin EU, Germany Email: email@example.com
kurz.nu is running on a FreeBSD jail which is maintained using ezjail. As a webserver i use Apache. The whole logic including database connection and rate-limiting is implemented into 161 lines of perl code. The webserver uses mod_rewrite and mod_perl. BerkleyDB is used via DB_File as a database. The per IP rate limiting is implemented using Cache::CacheFile. IPs are kept in the cache for 24 hours.