This page deals with typical dynamic sites or content such as asp pages which, although they may use a dynamic url, contain indexable content. There are other types of dynamic sites, such as those designed in Intershop or similar systems, that are completely un-indexable. If your site has been developed using such a system you will need to either design a second html based site or use the XML feeds that AltaVista and Inktomi offer on a PPC basis.

As optimising dynamic sites can be difficult I would recommend that you outsource the search engine promotion to a professional, ensuring that the SEO consultant you choose has a history of successfully promoting these types of sites.

A dynamic page contains content that is generated on the fly by taking results from a lookup table or database in order to satisfy a specified query. Dynamic sites are convenient for running shopping carts and quickly updating and customizing content, and while some sites make use of dynamic content for certain sections other sites are entirely designed within dynamic URLs.

You can usually tell if a page is dynamic by the "?" or other special characters located in the page's URL. Although all of the major engines can read pages using URLs that have non-alphanumeric characters in them (such as &, +, %, $, ?) they may not actively spider such sites, choosing rather to only spider the dynamic page that is directly submitted to them or directly linked to from a static page.

The reason the engines shy away from actively spidering dynamic sites is because they do not want to be caught in what is known as a "spider trap". Depending on how the site is coded, a single dynamic page can be generated hundreds of times - each with its own unique session id based url.

So If you want the search engines to spider your dynamic site you will need to either pay for inclusion (Inktomi, Lycos/Alltheweb and AltaVista offer this) and/or ensure that workarounds are put in place.

The best workaround for most dynamic sites is to get rid of any characters that are incompatible with search engine indexing. Most notably these include, ?, =, &. This can be done by creating scripts on the server that modify how it "serves up" dynamic pages. Even though the content is dynamic, the "normal" urls allow the site to be properly spidered.

If you have already built the site and you cannot change the url's using the present programming you will either have to pay to have the site redeveloped using technology that allows search engine friendly url's or you can opt to use other workarounds.

• Site Map - A good way to get the engines to index your dynamic pages is to create a search engine friendly site map. Use text links with descriptive (keyword rich) text and link to each of the important dynamic pages as well as any static pages that are on the site. Bear in mind that your human visitors will also be interested in this site map so make it user friendly. The site map should be visibly linked to from the homepage using an html link (not javascript or flash). Submit the site map directly to the engines.
• Static Site - If you cannot make your dynamic site search engine friendly then create a scaled down static version of it that links through to the dynamic site. Bear in mind that we are talking about a properly designed, full site, not a collection of doorway pages. Ideally this site should be purpose built to be search engine friendly and contain as much information as possible about the products/services being offered on the dynamic site. The links should ideally be to the relevant sections of the dynamic site so that the user lands exactly where they expect to without having to start their search all over again.
• Mini Sites - If the above is too costly another idea is to create 3 or 4 page mini sites targeting specific products or services offered on the dynamic site. The above criteria applies; search engine friendly, loads of information, relevant links to the dynamic content.
• Information Pages - Sometimes static information pages can be incorporated into a dynamic site such as About Us, Product Information or FAQ pages. Although on the dynamic site, these are static pages and as such are indexable.
• Doorway Pages - If you cannot create a full or even a mini static site another option is doorway pages. Please read the section on doorway pages very carefully in order to understand what I am talking about as there is a lot of misconception and dubious information and advice floating around regarding this type of workaround.
• Static Mirror Pages - One workaround that some use is to set up the server to generate one static page for every dynamic product page. The mistake I often see with this is the misconception that all that is necessary is a blank page with a title and meta tags. So the site ends up with dozens or even hundreds of what are effectively blank doorway pages with no body text and identical titles and meta tags. This is not a good idea and could harm a site's listings. If you are going to use static mirror pages make sure they are generated to include a product/service relevant title, meta tags and at least one paragraph of keyword rich content. Note that this is nowhere near as effective as a static site but if done correctly it can have a positive effect on the site's search engine listings.

Dynamic sites and search engines
Spider Food - Dynamic Page Optimization
ClickZ Solutions for Dynamic Page Registration
Search Engine Forums - Dynamic Pages
Webmaster Base - Search Engine Friendly URL's
Webmaster World Forum
ASP 101 - Extending Your Page Names
A List Apart: URLS! URLS! URLS!

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