Although GPRS and CDMA2000 can reach speeds faster than a regular dial-up Internet connection, they can't compete with a good solid Wi-Fi connection. But, they can get slightly closer by putting a little intelligence between your notebook and the Internet. Verizon and AT&T Wireless support a compressing proxy server . This involves two pieces of middleware that sit between your web browser and the Internet, which are described next.
The upshot of this arrangement is that you can expect load times to be significantly reduced in many circumstances. For example, under poor network connections (with the signal meter reading one out of five bars), Verizon's compressing proxy was able to transfer an 814-kilobyte text file in 98 seconds a speed of 8.3K per second. Compare this to a transfer under the same network conditions but without the compressing proxy, which took 15 minutes and 5 seconds! The compressing proxies can also compress images. Figure 8-29, Figure 8-30, and Figure 8-31 show detail from an image that was compressed using three different compression settings (lowest quality, highest compression, 6155 bytes; medium quality, medium compression, 10419 bytes; and no compression at all, 16918 bytes). Figure 8-29. Photograph showing maximum compressionFigure 8-30. Photograph showing a medium level compressionFigure 8-31. Photograph showing no compressionIn Figure 8-30, artifacts are barely visible; even though the file size is roughly 60 percent of the uncompressed version, it is hard to tell the difference between the two. You should ask your wireless carrier about this capability because they may not call attention to it when you subscribe for service. At the time of this writing, the following offerings are available from major providers in the United States:
|