Search Engine Optimisation UK Get Free DHTML scripts provided by   Dynamic Drive

Search Engine Optimisation, Internet Advertising & Search Engine Marketing Info

SPONSORED LINKS

Home   Resources      Site map

APRIL 2004

Google's Search Engine, Google's Change, Google's Data Center, Google Facts

Google uses something called distributed architecture (distributed computing). Google links over 15,000 normal pc's together across the globe via approx. 12 data centers. Our theory is that the network is broken down into 3 main areas, the core layer, distribution layer and the access layer.

At the core layer is the network back bone, this links up data centers via the distribution layer. The access layer is offered to the search engine interface (what you see when you visit google) for traffic direction and searching traffic. The core layer will probably connect to the global Internet via high speed connections.

The importance of such a design can add extra layers for redundancy, overflow routing for high traffic peaks, and the 15,000+ pcs spread out over the 12 or so data centers can be synchronised across this design on a regular basis.

The Google Dance

In the past each data center would go through a massive update each month. When the update was in a 'during' phase people could see major shifts in the SERPS (Search engine rankings). This was called the Google dance.

Further Explanation

When you type in Google into your browser, your pc sends a DNS (i.e. www.google.com) request to a DNS server (configured within your IP stack). Most ISP's offer something called DHCP (Dynamic Host Configuration Protocol) - this will set up your default gateway route and will tell your pc what server to send the DNS request to.

The DNS server resolves the domain name (translates the URL to an IP address). IP or IP addressing is more than just a number, at the hart of the Internet is something called an IP stack. IP protocols (most networks use version 4) will encapsulate your data into layers of organised information cells or packets for streaming. For instance destination address, source address, and other identification information (bit settings) such as TTL. (Time to Live)

When you do a trace route on the network the application sets the TTL to 1 and this counts down on each hop. When it gets to the first hop the TTL expires and ICMP sends back the response to your host. The application then sets the TTL bit to 2, then 3 and so on. Eventually you see a map of the network. If you go to to DOS and type in tracert www.google.com you will see each hop that connects you to the access layer device on Google. When your browser sends a request to www.google.com the TTL field (within the IP header) is set to 5 minutes, and the request is handled by the closest geographically placed server. If the server is down (i.e. hard down - has a network complete failure or just down - has too many requests) google redirects your request to another data center.

WHY NOT WORK WITH US TO BUILD A BETTER INTERNET - OUTSOURCE YOUR SEO WORK TO US

When each data center is at a different phase of the synchronisation process it is possible to see changes within the search results i.e. you search for cars on google and see a site at number 3, you then click refresh and the same site is at number 6 etc. Some of these ranking shifts could be quite dramatic, as a result Google now make smaller adjustments more frequently to control this problem.

The dramtic changes before were nicknamed the Google dance, as positions would dance around the rankings table.

When Google visits your web site, it makes an impression of each web site it stores in a data center, this impression is known as a cache. When you switch between data centers on Google you access information from different caches. The Google Dance is no longer alive in the sense that Google do not do a major update of cache synchronisation every month, they simply do smaller updates more frequently to keep the information up to date and accurate.

This process in real-terms is a Google convergence process.

Current List Of Data Centers

Current List Of Test Centers

If you want to get an idea of where you site is going to be placed a good trick is to visit www2.google.com or www3.google.com

They will show you a more accurate picture of what you can expect so see in the real SERPS.

Google Tool Bar

Google offer something called a browser tool bar that is a great utility to see what google think of your site, this can be downloaded here: http://toolbar.google.com/

Your tool bar connects to a data center, if you want to redirect this to a particular data center simply add a comment to your host file (or lmhost file) as follows:

216.239.59.100 toolbarqueries.google.com

Obviously you put the IP address of the data center you want to connect to.

Google Changes

Google's Technology Playground

Google's Page Ranking Explained

Website Business Reports Here!

Web Site Ranking Explained, Web Site Submission, Search Engine Optimisation Basics,

Internet Advertising, Google Search Engine Optimisation Guidelines,

Flash Intros, Web site Templates, Search Engine Relationship Chart

Search engine marketing is needed to successfully place your site on sites such as Google, Yahoo etc. unless you use PPC. If you are a long term PPC client the SEO will be better for your business long term.