Wireless LAN equipment maker Trapeze Networks has been busy lately, and this week the company demonstrated "seamless" mobility between a Wi-Fi network and a cellular network.Trapeze teamed with start-up DiVitas Networks to demonstrate their wireless platforms' interoperability with dual-mode voice handsets that support Windows Mobile 05. They were able to hand off voice-over-WLAN calls from the Trapeze WLAN to a cellular network.Trapeze also unveiled two WLAN Mobility Exchange switches, the MX-200 and MX-216, to support the Wi-Fi-to-cellular convergence. The MX-200 has two fiber or copper Gigabit Ethernet ports, while the MX-216 has 16 ports of 10\/100Mbps Ethernet and supports Power over Ethernet on those ports. Each box can manage up to 128 of the company's access points.Last month, Trapeze announced support for "network domains" in its Mobility System Software, which the company says can be used to ensure a consistent model for mobility, security and service delivery across thousands of branch office WLANs and manage all of that from a central location. It also allows managers to locate mobile devices anywhere within the extended wireless network. Trapeze says the management technology can scale to cover more than 32,000 of its switches.At that time, Trapeze shipped an outdoor access point called the Mobility Point 620, which supports IEEE 802.11a and 802.11b\/g WLAN technologies. The idea is to support wireless networking across a campus and between buildings. The company says users can ensure resiliency with redundant links, and can even bond the links together to reach aggregate speeds over 100Mbps.