The Next-Generation Networks (NGN) conference in Boston early this month was filled with education about wireless networks. I mentioned a couple areas of focus last time, 802.16 standards and public hot spots. Here are a couple of others:* Mesh network architecturesIn addition to the usual banter of thin-vs.-thick Wi-Fi access points and security discussions, the topic of self-organizing wireless meshes was more prevalent than at industry shows of yore. In such networks, access points relay information from one to another, hop by hop; much in the way routers work, only they communicate over the air. As you add users and access points, you add capacity.\u201c[Mesh networking] could eventually be a threat to the carriers in a \u2018power to the people, bottoms up\u2019 fashion,\u201d said NGN conference co-chair Dave Passmore, who is also research director at The Burton Group. In other words, as users adopt little islands of wireless connectivity of their own, in effect, they each build out a piece of the world\u2019s wireless infrastructure.* Health effects of\u00a0radio frequency\u00a0Many of you have written to me about this issue: Should we worry about so much\u00a0radio frequency\u00a0bouncing around all day long in our homes and offices? It seems that the jury is still out.Michael Gallagher, acting assistant for communications and information and administrator at the National Telecommunications and Information Administration (NTIA), the federal agency that serves as the president\u2019s principal adviser on telecom issues and authorizes spectrum use by federal agencies, said he is \u201cnot aware of any federal study of the effects of RF. No one has brought that concern up.\u201dSean Maloney, executive\u00a0vice president\u00a0and general manager in Intel\u2019s Communications Group, said there is \u201cno evidence of health issues with Wi-Fi and WiMAX networks, but the industry needs to do long-term research.\u201dTo find some information on some of the research that is underway in this area, visithttps:\/\/www.wirc.org\/research\/current\/index_cur.shtml* Voice over IP over Wi-FiLowenstein and Passmore agreed that combination Wi-Fi\/mobile WAN phones should be available sometime next year. (Motorola has already announced one.) But several representatives on a voice-over-WLAN panel agreed that there are still several outstanding VoIP infrastructure issues - in terms of internetwork roaming, end-to-end service quality and security - to be solved. We\u2019ll take a closer look at those in a future newsletter.