Global Roaming Initiatives make Progress

While customers have been able to roam within their home countries, and in some cases a few neighboring ones, the goal of making a wireless call from anywhere on the planet and having that call be reconciled and billed for accurately still eludes most carriers.

A number of issues—incompatibility among wireless protocols and record formats, international financial settlements, complications with wireless data—have kept global roaming from becoming a reality for many carriers. But significant developments in the past year will help bring down the technological barriers.

In October 1999 the GSM Association approved guidelines for a multilateral financial settlement program. The program takes the complexity out of dealing with foreign currency exchange and different languages and laws in other parts of the world. Cibernet, which provides financial settlement services for wireless carriers, is supporting the GSM Association’s global settlement program, says Mary Clark, vice president of operations at Cibernet.

“Roaming issues become moot, because now ANSI-based carriers [mostly based in North and South America] don’t have to worry about settlement if they want to roam with GSM carriers,” she says. “Settlement has been complex in the past, and administratively burdensome; now it’s much more of a streamlined, cost-effective process when ANSI and GSM carriers have an outsourced place to go.”

Another development occurring with many Latin American and Asian carriers involves authentication. “These carriers are starting off with the prerequisite of authentication, which is different from how it developed in North America,” Clark adds. “With this prerequisite, you’ve got a box checked that makes global roaming not that much of a concern to a desirable partner.” Clarks notes that new Latin American carriers are making sure they have SS7 support, automatic roaming, the ability to settle, fraud containment and authentication on their list of issues to resolve before going online.

Data Complications

Another key area being actively addressed is how to deal with data, as carriers begin to offer wireless Web, e-mail and other services. Currently, data transmission is being supported only within networks, Clark says. “There’s really no roaming going on with data. There are some data services that can be roamed with, such as short message service [SMS], but traditionally the data folks were treating them simply as a call,” she says.

Carriers may charge based on duration of a data event or a flat charge per event. “The key is a shift in thinking, because we’re not talking about an event that has a start and stop time,” says David Diggs, vice president of global marketing at Cibernet. “We’re talking in terms of variable bandwidth, how much network resource was consumed and priority of packets. It remains to be seen what the pricing principles will be.”

While it may not be clear how wireless data services will be billed for, record formats being developed will address this question. Cibernet is developing a wireless data record that will support packet-based data and bill by event, duration or bandwidth. The record format will also support international roaming. Cibernet’s goal is to have this record format released later this year, with carrier adoption occurring about a year after that. This will bring the CIBER record format, used by AMPS-based carriers to exchange roaming records, to version 2.5. In addition, GSM carriers should be able to implement the TAP3 billing standard, which includes provisions for data, by the second half of this year.

GTE Telecommunications Services Inc. (TSI) is also providing some data roaming services through its Global Roam service. The service allows subscribers with IS-41 service (a protocol adopted by the ANSI community) to roam into GSM, and vice versa. However, this service is for traditional data transactions, such as for laptops connected to home offices or the Internet, and is not handset-based, says Bill Gerhardt, group product manager for fraud and network at GTE TSI.

But he adds that through the wireless access protocol (WAP), data roaming will improve. Through GTE TSI’s Commercial Location Service, the company plans to roll out WAP-enabled services this year. This will enable GSM subscribers roaming in North America to receive content on their handsets. The content they receive will not be from their home carrier but through a North American provider. Gerhardt doesn’t think subscribers are too far away from being able to get local content from their own operator while roaming. He says this could be achieved through a cellular digital packet data (CDPD) network, which could query the Internet and bring back the requested information.

This would be different from WAP, which downloads data to a handset through agreements a subscriber’s provider has with content providers. In the WAP space, GTE TSI is offering a voice-activated system with services like Yellow Pages and traffic reports. The company is moving toward allowing that information to come down through a WAP-enabled phone so the information can be presented visually.

A Single Record Format?

It’s highly unlikely that CIBER and TAP will be replaced by a common standard, because both are entrenched within their respective user communities, and a significant change could cause problems for legacy systems. Also, clearinghouses that handle the mapping from one record format to another already have found convenient ways of reconciling billing records. “The move to a common record format would have to be driven by the carriers themselves and the standards bodies,” says Gerhardt.

Gerhardt adds that although there are similarities between CIBER and TAP, there are still too many differences to have a single billing format. He does point out that when TAP3 comes out, it will have more of the look and feel of CIBER. He also says that by the end of 2000 or early 2001 the GSM record format will start supporting rejects of billing records, a process that has been part of CIBER.

“This support of rejects or returns ensures payment from partners and is more involved with revenue assurance from an auditing perspective,” says Dave Estes, product manager for clearing at GTE TSI. “Today [in the GSM world], they don’t edit all the way down to an individual call record; they just edit a file that could contain thousands of call records. In the CIBER world, if there is one bad call record, you can just reject that one but process the good records in that file instead of throwing them out.”

Roaming Hurdles

Experts agree that it is crucial to have a handset that can work in different wireless environments seamlessly. “I think that there will ultimately be enough chipset advances such that a phone has all the standards built into it and can be personalized based on users’ preferences or travel patterns,” Estes says. And if vendors only had to keep one kind of phone in stock, he says, it would be much cheaper. “I think this will come about eventually, but one issue right now is that manufacturers are understandably reluctant to build a multimode, multiband phone absent a large order.”

“As handset manufacturers produce compatible handsets, it’ll help because in the back room all the signaling and billing issues are already being addressed,” Gerhardt says. “There are manufacturers that are in the process of rolling these types of handsets out, and I think it’s just a matter of time before subscribers say that this is the type of handset they need.”

Another technical hurdle being addressed involves including unique identifiers within wireless devices. The simple phone number you receive when signing up for wireless service is usually not enough, because countries assign phone numbers differently. This means that technically one phone number could unwittingly be used by multiple devices issued by different carriers in different countries.

One resolution to the problem comes in the form of the International Roaming Mobile Identification Number (IRM), which guarantees that the mobile devices can be accurately identified without confusion. However, most of the numbering in the IRM scheme has already been allotted, and not all carriers have applied for an IRM. A second possibility to resolve the issue is the International Mobile Station Identifier (IMSI), a 15-digit number that’s already being used by GSM operators. This may eventually be adopted by North American operators as well. “International carriers that want to roam in North America have to use an IRM or roaming number that’s compliant with the North American numbering plan and doesn’t conflict with current system identification [SID],” Estes says. He adds that the TAP record format has been accommodating IMSI for billing, and he says that ANSI-based carriers will eventually move toward this standard as well.

Cibernet’s Clark feels the technical issues are slowly working themselves out and that now the only significant challenge is for carriers to make pursuing business relationships with other carriers their primary objective. “With roaming revenues in North America dropping significantly, international roaming is being considered a very valuable activity to engage in, because it will increase the competitive edge and roaming revenue,” she says. “I think it is the business relationships that are probably the next frontier.”

GTE TSI has also noticed that the lack of partnerships remains one obstacle to international roaming, and in response to that has created the Universal Roaming Services Alliance to facilitate international roaming and provide roaming agreement consolidation for carriers. “The drawback we hear from international carriers is that they don’t have the contacts here in North America to obtain roaming agreements; given the fact that we have relationships with a lot of carriers, they look to us,” Estes says. GTE TSI has relationships with some 180 wireless operators in North and South America, Asia/Pacific and Europe.