Top players in both the vendor and carrier space are pitching in to advance GAIT-GSM ANSI Interoperability Team-a new network standard that fuses TDMA and GSM technologies to enhance roaming, preserve TDMA and serve as an interim solution in the sojourn to the third-generation of technologies.
The technology, which is a software upgrade providing seamless interworking of both networks, anticipates a single dual-band mobile phone to bring the dream of the players to fruition.
While demonstrating active zeal, no company is ready to reveal details of its inroads into GAIT.
The manufacturers involved in this project include Nokia Corp., Alcatel, Panasonic Inc., Lucent Technologies Inc., L.M. Ericsson, Sony Corp., Texas Instruments, Philips Corp., Compaq Inc., Mitsubishi Corp., Motorola Inc., NEC, Gemplus, Nortel Networks, Siemens AG and Intel Corp.
The operators investing in GAIT are Cingular Wireless-which is growing into the bellwether of the standard-AT&T Wireless Services Inc., VoiceStream Corp. and Cable & Wireless plc. The GSM Association is the umbrella organization advocating the GAIT standard.
“GAIT is not an infrastructure,” explained Bryan Prohm, senior analyst with Dataquest. “It is a network.”
Prohm said it is a lifeboat for TDMA and for carriers to retain their valuable subscribers. “It’s a strategy to maintain the integrity of their user base and maintain brand loyalty,” he commented.
Prohm said from the viewpoint of new handsets, TDMA phones “will be a relic of the past within 18 months.”
As to whether the technology would pre-empt third-generation services or have too short a life span to justify the investment, Jack Kozik, Lucent’s director of enhanced services infrastructure, said, “We are happy to support our customers.”
Cingular said it is working with several vendors to build its network, which will be ready either in the fourth quarter of 2001, or in the first quarter of 2002. The company, however, would not disclose the manufacturers.
Neither would Lucent or Nokia, although Nokia spokeswoman Virve Virtinen noted the Finnish company has been involved with the project from its inception.
Ericsson said it is helping to build AT&T Wireless GAIT networks, but would not reveal any further information.
Lars Nilsson, Ericsson’s manager for strategic marketing, said Ericsson builds the network by installing a backbone protocol called Roaming Free GAIT-Way, which enables interoperability with both TDMA and GSM networks by using a Mobile Application Part to connect the two networks. The Roaming Free GAIT-Way connects both technologies the same way ANSI 41 facilitates TDMA-to-TDMA roaming.
“You don’t need a new base station or MSCs (mobile switching center) for GAIT,” said Nilsson.
Explaining its dynamics further, Kozik said GAIT enables a dual-mode handset to speak to both radio technologies so that the subscriber can access data in both networks through the interworking and interoperability function (IIF), which translates data from each network’s home location register (HLR).
“The IIF reformats and migrates the data sitting in the HLR,” said Kozik.
Citing Cingular as an example of a carrier that needs GAIT because of its variety of networks spread across the country, Kozik said GAIT “combines heterogeneous mobile networks and wants to offer services worldwide and helps homogeneous networks that are about to become heterogeneous.”
Siemens is the only name that has been identified with a GAIT mobile phone, but the German phone maker denies making any such handset, although it said it is looking into it.
However, Siemens rolled out its S46 phone during the Cellular Telecommunication & Internet Association trade show in March, which has been misunderstood as a GAIT phone because it is both GSM and TDMA compliant.
“It is not a GAIT phone in the true sense of the word,” clarified Martin Fichter, Siemens’ director of product management. “It is a phone that works in GSM and TDMA networks and can roam in both networks’ coverage areas.”
He explained that Siemens’ S46 phones can perform 95 percent of the functions of a GAIT phone, but that does not make it a GAIT phone because the remaining “5 percent is the fine-tuning of the interworking between TDMA and GSM.”
He said GAIT is one standard, but his company’s S46 phone only connects two distinct standards in one phone in such functions as transmission of SMS and over-the-air provisioning of data. But a GAIT phone will work as if from one database. The S46 phone cannot work on GAIT networks.
“From the user experience, you can’t see the difference between the S46 phone and GAIT, but it’s a standards issue,” he said.
He said the S46 is also GPRS-enabled and targets users who live, travel and work in metropolitan areas.
Nilsson said the recent merger of the handset divisions of Ericsson and Sony to form Sony Ericsson “puts a lot of questions into” whether his company would roll out a GAIT handset.
“When the time is due,” he noted, “we will look into it and have been looking into it for quite some time.”
Kameron Coursey, Cingular’s director of technology and product realization, said his company decided to build the network because some of its subscribers have had to use GSM networks like Voice-Stream when they roam outside Cingular’s TDMA coverage areas. VoiceStream is also involved in GAIT.
But Coursey would not disclose if that is how his company is tackling the issue of a possible GSM overlay on its TDMA networks, an issue that has foddered speculation since AT&T Wireless announced its intention to adopt the hybrid network.
“GAIT is an example of a trade-off between building a brand new 3G network and evolving a mobile network already in place,” remarked Kozik. “It is a matter of economics.”
The GSA began working on GAIT in 1999 when it created the GSM Global Roaming Forum to enable collaboration between GSM operators and providers of “other digital technology standards, including TDMA, CDMA and iDEN.”
