On reducing troubles in your Web site
 
 
When a visitor browse a webpage, their browsing experience depends on many factors such as connection speed, computer hardware and software, internet provider etc. But a good web design also plays an important role in browsing speed. Pictures and graphics are powerful ‘hooks' for customers, and can easily help a browsing session. When they are used incorrectly, they can create bottlenecks that block the message from your site.
 Remember few important facts if you make an image mosaic: 
First: The page load time increases according to the number of page elements, even if their total size remains the same. 
Second: However, page elements merging will lead to a longer duration until your visitor sees the first portion of your webpage.
You have to set certain priorities in designing a webpage:
i. A fast browsing experience or maximum visual impact.
ii. Making you're your visitors to stick on your site.
The web designers who use graphical navigation have many choices:
•i.                     To include graphics and text,
•ii.                   To just work from one large image with several navigation elements, 
•iii.                  Or to load many small ones. 
 The latter is a popular method today, but takes slow access. This slowdown is particularly noticeable on dialup connections. If you have a bottleneck in this area it can affect all of your users but server requests are less affected by download speed.
The server request process: 
First Step:  The User clicks a link, and the browser sends an HTTP request to the server. 
Second Step: The request goes through Internet hosts and routers, and then reaches the server. 
Third Step: The server processes the request and sends the HTTP response and data back; 
Fourth Step: The response goes through the Internet, usually on a different route, and then reaches the browser and the element rendered by your browser, and displayed on your screen. 
 There are two main factors to calculate the effect of this complex process on the customer experience: I. the "Internet latency time." and II. The "HTTP request". 
The typical minimum size of an HTTP request is 256 bytes. This means that when browsers request an image of one byte in size, the browser needs to send a 256 byte HTTP request on both of its server connections, and the server has to send back an HTTP response of the same size, along with the one byte of content. 
You can use the following formula when calculating the contribution of HTTP request delays: HTTP Time Loss = (4 kilobits) * Elements / Bandwidth in kilobits per second.
The number of page elements is between 10 and 30 on a regular website. And so here, the HTTP overheads will add significantly to your load time. For example, in a page with 50 elements and a 56kbps connection speed, 3.57 seconds of page load time is wasted. When the page size is 100KB, the ‘expected load time' is 14.28 seconds but actual time is 25% greater. 
Internet latency time involves how the packet (request) gets to the server and back (steps 2 and 4). The amount of time this journey takes is known as "ping time". The shortest possible ping time to the other side of the world is 85 milliseconds. That is because 85ms is the time the electrical signal needs to travel to the other side and back in a straight line through the Earth. Of course, the shortest possible ping across the world is 133ms, as we cannot cut through the Earth. In practice on overseas websites, the actual ping is often higher, over 300ms not being unusual. To local sites inside the USA and Europe, typical ping time can be 100ms or lower (Source: http://www.internettrafficreport.com)./ 
Internet latency time loss = Elements * (PING in milliseconds / 1000) / 2.
In the above formula, "2" is the necessary correction factor that browsers usually make more than one connection to the server. 
It is possible to incorporate ping delay time and HTTP header request delays, described above, into a final formula: 
Total loss of time = Elements * (4 kilobits / Bandwidth + PING / 2000) 
Despite the growing penetration of broadband in the world many users still suffer from slow page load time. This can drive users away and does not encourage return visits. According to Nielsen Net Ratings, over 60% of US households and 85% of US work users are now broadband equipped.
Just decreasing the size of the smaller images on your site doesn't help significantly if they are already less than 500 bytes. Try to decrease the number of images by combining them into one or more large images. You can use image maps for this purpose, which work from the position of the mouse on the image and are a good way of cutting down on the problems caused by fragmented images. 
The quickest way in grasping the "Mosaic Layouts" concept is that when you add ten elements to your site,(no matter what their size)you will commonly add an extra second to your load time.