Walker Wireless plans to integrate Wi-Fi and under-trial mobile phone technology in its wireless “hotspots” programme.
Last year Walker began trialling the hotspots — access points to wireless networks — using Wi-Fi (also known as 802.11b) wireless technology at Auckland airport and several hotels, restaurant chains and some service stations.
However, the planned full rollout of the programme is on hold as UMTS TD-CDMA, to which Walker switched late last year after initially deciding to deploy non-line-of-sight technology MMDS, is being trialled.
“UMTS TD-CDMA is a fantastic technology, but we have to review the synergies between it and 802.11,” says sales and marketing manager Alan Lee. UMTS TD-CDMA and Wi-Fi are, however, “very complementary”, he says. Wi-Fi is a short-range wireless technology whereas UMTS TD-CDMA is a broadbrand technology designed for mobile phone coverage. Telecom uses a version of CDMA for its new cellular network.
Walker’s networks general manager, Andrew McPherson, says the postponement of the hotspot rollout while the wideband CDMA technology is being tested is necessary because Walker wants to ensure there will be interoperability for its customers between UMTS TD-CDMA, 802.11b and GPRS — an update on GSM cellular technology being used by Vodafone — under a recently approved roaming protocol, MobileIP.
Under MobileIP, says McPherson, “you may have 802.11b plugged in and a UMTS TD-CDMA or GPRS modem and if it loses a connection on one it will attempt to make it on another, keeping the same session open”.
It does so by working with two IP addresses; first the user’s home address and then — when the move to a different network is made — a randomly assigned one on the remote network to which traffic is forwarded to from the home address.