NEEDS OF WIRELESS HOME NETWORKING APPLICATIONS
Today's home networking applications[7] are driving the need for a high-performance, wireless network protocol with high usable speed (high network throughput) and isochronous, multimedia-capable services. Factors driving the need for high performance are:
[7] This section has been adapted from ShareWave's white paper on wireless home networking, "Whitecap(tm) Protocol: High-Performance, Wireless Home Networking," October, 1999.
Home networks incorporate multimedia— Existing and emerging digital devices such as televisions, DVD players, digital video recorders, digital audio/MP3 players, DBS systems, flat-panel displays, digital set-top boxes, and PCs create the need to support multimedia content in the home (Figure 8.1). The home network will have to support all types of digital content, including local content (e.g., DVD, MP3) and broadcast content (e.g., video on demand, streaming media). This content is multimedia in nature, encompassing audio, voice, video, and data. Internet multimedia broadcasting is already prevalent. Other initiatives such as Internet phones, VoIP, MP3 online music, and broadcast media applications such as RealNetworks'RealGuide, Microsoft's Media Player, and Cisco's IP/TV, ensure that multimedia content will continue to grow in home networking.
The ability to support multimedia is the "killer app" that will drive the mass adoption of home networks. Therefore, a home network must support the coexistence of batch data (print jobs, file transfers) and isochronous content (video, voice, audio). The consumer needs to choose products today that will provide the foundation for multimedia network services.
Figure 8.1. Home networking scenario. (Courtesy of ShareWave)
Consumers are adding more nodes to their home networks— As mentioned earlier, the rapid growth of multi-PC homes indicates that the number of nodes in a PC network will continue to skyrocket as home networking appliances are introduced. It is estimated that by the year 2002, 33 million (or 55%) of the projected 60 million U.S. PC-owning households will have at least two PCs. Cahners In-Stat predicts that the average number of connected nodes per home network will increase from 2.9 in 1999 to 5.0 by 2003.[8] Simultaneously transmitting wireless appliances share the same bandwidth. Consequently, high network throughput and usable speed are necessary to accommodate more home network appliances. Choosing a wireless network with an access mechanism that supports multiple nodes without significantly degrading total throughput is essential to supporting a growing home wireless network.
[8] Cahners In-Stat, "Home Networking: Markets, Technologies, and Vendors," January, 1999.
The need to preserve high-speed broadband Internet access— The desire for faster Internet access is driving the mass deployment of high-speed broadband access, such as xDSL and cable. Cahners In-Stat group predicts that by 2002, 45 million homes will have installed high-speed modems.[9] Cable and xDSL broadband are targeting and delivering bandwidth speeds in excess of 6 Mbps. Consumers need a high-performance, wireless network to preserve, and not bottleneck, high-speed broadband Internet access to devices.
[9] Cahners In-Stat, "Videoconferencing and the PC Camera Market," March, 1999.
Evolving personal computer applications— File sizes of typical personal computer applications are growing rapidly with each generation of standard software applications. The file size of a word processing document with the same content has doubled over the last few years. Graphics and digital photography over e-mail are now commonplace. Files sizes greater than 20 MB are not uncommon for digital photos. A wireless network with high, usable throughput is mandatory to move files in a timely manner. For example, moving a 2 MB file over a 1 Mbps network with low effective throughput may take as long as three minutes. This need is further magnified as the network volume expands and more nodes are added.