Studies estimate that 10-20% of all hand-entered URLs are mistyped, adding up to at least 20 million wrong numbers per day, helping to enrich the likes of porn purveyors, ISP’s, Paxfire, Microsoft and VeriSign.
而 Paxfire 我並不熟，但是我剛剛查到的內容是這樣寫的：
Paxfire Inc. has developed a proven, patent-pending technology for ISPs called “HotWords” to perform address-bar searches and mistypes at the network level. HotWords enables ISPs to capture keywords (e.g. cars, books, etc.) and typos made by subscribers without the need for any desktop plug-in or other client-side software. A user can type a keyword or any mistyped domain name directly into the browser bar and get a search result with sponsored links. When a user clicks on one of those links, the ISP then gets a share of that revenue.
看起來像是 Layer 7 filter 或是 transparent proxy 的技術過濾後 redirect 到他想要的網站。