URL Rewrite - ISAPI Filter for MS IIS


URL Rewrite is an ISAPI Filter for Microsoft IIS (ASP, ASPX, CFM, PHP, JSP, etc.) that allows a webmaster to use static URLs on the fly in IIS. The product is basically designed for search engine optimization, search engine ranking, search engine exposure and promotion without effort because it overcomes the problems associated with dynamic pages and allows dynamic sites to be indexed by search engines as if they were static HTML files.

Speaking of Filters

I want to alert those of you about a FDA Warning regarding the IVC Filter, a medical device recommended for people who are at risk for (deep vein thrombosis) DVT and can not be treated with blood thinning medications. A friend of mine, Z, had what we all thought might have turned into a life threatening scare with the IVC filter that his surgeon had implanted when Z didn't respond to the blood thinning meds he was on. There are numerous lawsuits are being filed by IVC lawyers claiming that certain IVC filters have design defects, manufacturing defects, resulting in breach of implied warranty, and negligence. Most of te lawsuits are against two manufacturers, the main culprait being Bard. The FDA recently issued a warning letter (July 2015) to C.R. Bard, Inc. and Bard Peripheral Vascular, Inc. (collectively referred to as "Bard") for eight violations of federal law relating to the safety of its Inferior Vena Cava (IVC) filter product line. Z had read about the FDA warning online and freaked out, as I would or for that matter any of us might have. Turns out that his filter was not a Bard and that his docter plans on removing it once the threat of his DVT is past.

If you know of anyone who has had an IVC filter implanted, give them the heads up regarding the FDA warning.

Fortunately the URL Rewrite filters we are discussing here do not and never will cause a threat to your well being or health.

URL Rewrite is available as a high performance IIS C++ filter primarily intended for database driven catalog type web sites seeking to increase exposure by allowing spidering search engines such as AllTheWeb, AltaVista, AOL Search, Ask Jeeves, Google, Hotbot, Inktomi, Lycos, MSN Search, Netscape Search, Overture, Yahoo, Teoma and many others to index the values behind a querystring. e.g. products.asp?type=computer&product=123

URL Rewrite is compatible with Microsoft's ISAPI specification, and has been tested on Windows 2000 Server running IIS 5 and Windows 2003 Server with IIS 6.

Product Description

A database driven website pulls data from a database, and basic query string usually looks like: http://www.domain.com/products.asp?type=computer&item=123. When a search engine spiders and indexes this page it will only index http://www.domain.com/products.asp and automatically chops off everything after the "?". This is where URL Rewrite filter helps you. With this filter you may create a gateway, or doorway pages, or replace all dynamic URLs on your site by "static" URLs and let search engine to spider all of your dynamic pages.

With URL Rewrite for dynamic link [url1]:


you may use following "static" format [url2]:

http://www.domain.com/web/type/computer/item/123/products.asp, or

and still use dynamic link [url1]!

All parameters (in this example - type, item) and their values ("computer", "123") are transformed to "directories" and separated with a directory slash "/". Notice, the link url2 does not exist, but url1 does! When this "static" url2 is requested by the browser, IIS and the URL Rewrite filter internally converts url2 into url1 but maintains the original "static" URL, which is a valid to the search engine. A /web/ folder does not exist and it is not parameter from url1, this is how URL Rewrite knows to convert the URL to a readable server page. A /web/ suffix is configured in INI file and instead of /web/ you can use more relevant string (e.g. if your website sell cars, then it is better to use another suffix like /cars/, /auto/, or /buyacar/, because search engines also attaches value to URLs).

Frequently Asked Questions


1. What is the main difference between URL Rewrite and other similar products on the market?

    URL Rewrite uses a straight forward algorithm optimized for the performance so that we do not use regular expressions and other surplus configuration. Because of that URL Rewrite is the fastest (and cheapest) rewriting ISAPI Filter for the moment.

2. Can I use dynamic links if URL Rewrite is installed?


3. Does URL Rewrite change dynamic links on my web pages to static links?

    No, it doesn't change your pages. It gives possibility to use second URL address only and if you want to use dynamic URLs you have to change links on pages yourself.

4.  Can I have relative links on my web pages with URL Rewrite?

There are following possible solutions. Because of the suffix ("web") your old relative links will not work and you have to change them, e.g. to "/web/image1.gif" instead of "image1.gif", < !-- include virtual="/..." instead of < !-- include file="..." Other way is to use

tag in section, e.g. then you could use usual relative links, like "image1.gif".

5. Do I need change all dynamic links on my website?

It's up to you to find out the right solution. It is recommended to change pages which you want to optimize for search engines, for example, product catalog, sitemaps, and so on. But some pages, like Privacy, Help, etc. could be still used with dynamic URLs.

6. What do I do if I have subfolders?

Put the suffix after subfolder(s). E.g. in case of following dynamic URL:


the static link has to be following

http://www.domain.com/scripts/web/type/computer/item/123/products.asp, or

For all further questions about URL Rewrite please contact us.

What Our Customers Say

With a several tens of the customers we can promise you 100% satisfaction of our product. See what our customers say about URL Rewrite. Kevin Adler, www.adleraudio.com: "I think people will be impressed by URL Rewrite once they use it, its simple, straight forward, and CHEAP! One company quoted me $510.00 for the same type of filter! Then they wanted to limit my usage to 10 domains! I installed URL Rewrite Filter on my server." (since May, 2003 about 7500 pages in Google). Tim Cormier, www.machinebox.com: "We are running our ecommerce site using this ISAPI filter. We love the product." (since August, 2003 about 300 pages in Google). Other good examples of using URL Rewrite could be found at www.customize-my-phone.co.uk, since August 2003 about 13500 pages in Google, www.tarkett-commercial.com, since September 2003 about 2500 pages in Google.


URL Rewrite is available with server license (cost per server is EUR 23.00, for unlimited web sites per server) and sold as ESD, which means you get the URL to download the full version and installation instruction immediately after purchase.