e networks, mobility networks, control networks, and wired networks, each of which is best served by one or another alternative. The success of HANs depends on standard products that are operable with a variety of physical infra- structures, SO we'll see the use of voice-grade telephony wiring, coax, electric pow- erlines, wireless, and fiber. The wireless approach has by far the greatest penetration today, using the popular Wi-Fi standard for wireless LANs. HANs over Phone Lines One approach to HANs is the use of existing phone lines (see Figure 12.11). The Home Phone Networking Alliance (HomePNA; www.homepna.org) is a major interest group in this space. HomePNA, which is composed of more than 150 com- panies, is an incorporated nonprofit association, and more than 25% of it member companies are outside the United States. HomePNA's main objective is to work toward establishing and ensuring compatibility with standards among telecom, computer, and network products. Although HomePNA does not enforce standards, it does advise the ITU-T. And although it does not actually manufacture any prod- ucts, it does endorse products as being HomePNA certified. HomePNA develops triple-play HAN solutions, supporting multimedia home networking services, such as VoIP, data, and SDTV/HDTV, over existing phone or coax lines. The technology provides data rates up to 240Mbps, with guaranteed QoS, enabling service providers to support multimedia services in the home, including in-home distribution of broadcast IPTV and networked PVRs. The HomePNA specification has been through several versions. The most cur- rent is HomePNA 3.0. (The 2.0 version was approved by the ITU-T as a global standard and is formally known as Recommendation G.989.1, with subsequent upgrades to G.989.2 and G.989.3.) HomePNA 3.0, announced in 2003, allows the RJ-45 Ethernet Cable Server RJ-11 Multipair Cat 5 Cabling Connecting Block/Hub Network RJ-11 Interface Device Figure 12.11 A HAN over phone lines Chapter 12 Broadband Access Alternatives networking of home c