Advertising is a multi-billion dollar industry on the Web. The Internet Advertising Bureau reported that web advertising grew by nearly 34 percent in 2006 over 2005, totaling about $16.8 billion (IAB 2007). The yearly growth rate of Internet ads is increasing at 28.6% per year, while the overall ad industry drags along with an increase of only 7.7% a year (Baker 2004).
Website Optimization
Optimize Parallel Downloads to Minimize Object Overhead
With the average web page made up of more than 50 objects (Krishnamurthy and Wills 2006), object overhead now dominates the latency of most web pages (Yuan 2005). Following the recommendation of the HTTP 1.1 specification, browsers typically default to two simultaneous threads per hostname. As the number of HTTP requests required by a web page increase from 3 to 23, the actual download time of objects as a percentage of total page download time drops from 50% to only 14% (see Figure 1).
Use Delta Encoding to Compress RSS newsfeeds – delta compression saves bandwidth
Delta encoding (also called delta compression) is a way to update web pages by sending the “diffs” or deltas between versions of a web page. The server (proxy or origin) sends only what has changed in the page since the last access. This technique greatly reduces the amount of data that is sent from server to browser. In some cases with pages that change slightly, the deltas are on the order of a few TCP/IP packets. As about 32% of page accesses are first-time visits, about 68% of page visits are eligible for delta compression.
Suture CSS or JavaScript Files to Reduce HTTP Requests
A server-side variation of merging CSS and JavaScript files before uploading to the server is to do this digital suturing at the server. You can “suture” CSS or JavaScript files together before delivery from the server to save HTTP requests. Often developers create separate style sheets and scripts for organizational purposes, and import them into their pages as needed. There are two problems with this approach:
CSS Sprites: How Yahoo.com and AOL.com Improve Web Performance
CSS sprites group multiple images into one composite image and display them using CSS background positioning. You can save a significant amount of HTTP requests by consolidating your images into one or more composite sprites and using CSS to selectively display parts of the sprite within your web page. Now that the major browsers have evolved enough to support CSS backgrounds and positioning, more sites are adopting this performance technique. In fact, some of the busiest sites on the Web use CSS sprites to save HTTP requests. In this article we’ll expand on our mini-CSS sprite example (mono-image CSS rollovers) to show how Yahoo! and AOL use sprites to improve performance.
Mono-Image CSS Rollovers
CSS is traditionally used to create rollover effects with two or more images for menus and other elements. Menus can use on, off, or visited images to signify the state of the menu. Typically menus are created using multiple background images, however. The problem with this method is that it doubles the necessary HTTP requests and can cause flickering problems when the “off” image is not preloaded. A better way is to combine the on and off state images into one mini-sprite and switch the background position on rollover (see Figure 1).
Minimize Noise to Maximize Graphic and Video Compression – tips to optimize web videos and images
Multimedia compression can be thought of as a war against unnecessary noise. Noise is the unwanted random dot pattern overlaid on videos and graphics when electronic noise is present, due in part to the random motion of electrons. Noise creeps into images, both still and motion, with the more lossy steps you take when manipulating images. These random dot patterns, or “snow,” prevent compression algorithms from working optimally, increasing file sizes. By minimizing the noise in your original images and videos, you can gain the maximum amount of compression when optimizing images and videos destined for the Web.
Web Video Optimization Tips – optimize streaming media for website videos
While streaming-media files make up only a small portion of the total web objects on the average web page, less than 1.3% according to Levering & Cutler (2006), a small fraction of streaming media is responsible for nearly half of the streaming media traffic (Chesire et a. 2001). In fact, YouTube is responsible for about 10% of all traffic on the Internet (Nowak 2007) and is growing at over 162% a year (see Table 1). Consequently the optimization of streaming media, movies in particular, is important to minimize load times, reduce bandwidth bills, and maximize web page speed.
Home Page Usability and Credibility Survey – Fortune 30 versus Inc. fastest growing companies
The key to fast growth online is rapid customer responsiveness (Weill and Ross 2004). How a company executes its own web site is one indicator of how a company executes IT projects and values customer responsiveness. In order to determine the usability and credibility of top websites, researches from Minnesota State University compared the home pages of the fastest growing companies against the Fortune 30 (Brown, Rahman, & Hacker 2006). The researchers found that the largest companies in the US used designs that were more consistent than the fastest growing companies, as defined by Nielsen and Tahir’s best practices (2001). The fastest growing company home pages fared significantly worse in performance metrics.
Update: Pro Ball Head Review – compares ball heads to give sharper photos & solid video support
Ball heads provide stability and mobility for photographers on the go. Combined with a stable tripod a solid ball head can help dampen out vibration for sharper photographs, especially for larger enlargements. Sharper photographs and videos make for smaller, higher quality multimedia for the Web. This article reviews some professional ball head options and looks at vibration testing with a laser vibrometer.