Content area
With wireless carriers striking deals with application service providers, Internet portals and anyone else touting flashy data offerings, wireless data is moving from hype and speculation to reality. Testing is more prevalent now than before. Carriers have been voice providers, and now it is all new with data. Because quality of service (QOS) was not as high a priority for voice-centric carriers, the move to offer voice and data will transform the way wireless operators approach their networks today. Most everyone realizes that the data revolution will increase the need to test wireless networks. But data is not the only thing demanding attention from test companies. Roaming, for one, is still a significant test point. Two entities such as Internet technology and wireless communications could not have been expected to converge without a lot of pain. And they will not blend successfully for the consumer without innovative data applications and a network that can deliver quality.
Full text
T&M developers tend to remain behind the scenes in the wireless industry, but their solutions could become a commodity once data takes hold
The wireless industry is in overdrive. With wireless carriers striking deals with application service providers, Internet portals and anyone else touting flashy data offerings, wireless data is moving from hype and speculation to reality.
At this point, wireless network testing may not be high on carriers' to-do lists, considering that most of those carriers currently are more focused on establishing their data networks. But while network testing is not the sexiest wireless topic, it stands to become just
as important as wireless data strategies themselves, especially when it comes to ensuring quality of service (QOS) for customers.
The marriage between the Internet and wireless still may be rocky, but test and measurement companies such as Agilent Technologies agree on one thing: "Testing is more prevalent now than before. Carriers have been voice providers, and now it is all new with data," says Eric McHenry, Agilent's general manager for wireless network solutions. The evolution of wireless data networks and the maintenance they will require is just beginning.
QOS takes top priority
Because QOS was not as high a priority for voice-centric carriers, the move to offer voice and data will transform the way wireless operators approach their networks today, says Matthias Nitschke, manager of Tektronix's monitor and protocol test design center. "With [IP] data in the wireless world, carriers will have to test user services in IP, which is quite a change," Nitschke says.
To test voice and data, carriers first must address the entire lifecycle, which starts with the equipment manufacturers and test companies with which it has worked. The process then moves to system integration and how the system gels with the protocols. The system's components then can be tested in a lab to simulate how they will connect with carriers' networks.
"People didn't really monitor voice traffic, but with IP they will need to monitor traffic and how it is executed," Nitschke says. Conformance testing will follow to ensure that technology implementation is conforming to whichever standard the carrier uses.
"Standards are still changing, however, and this is like a game. Whoever is the first test equipment vendor wins. Everyone is pushing so hard to be the first with a 2.5G test solution," Nitschke says.
Protocol testing will be just one method used to ensure network performance. A protocol test is the core competency in wireless network testing, Nitschke says.
The fact that, until recently voice had been the only service going over wireless networks makes signaling critical for ensurfing the quality of calls. Signaling has three basic functions: monitoring the status of a line, alerting the user of an incoming call and addressing or transmitting routing and destination signals over the network. Operators can test signaling by connecting a Wireless Application Protocol (WAP) phone to the network and monitoring whether the call is set up correctly to transport IP traffic.
"The most important thing a carrier should look for is test equipment that measures QOS," says Keith Radousky, director of engineering with BellSouth Cellular. Currently, general packet radio service is a best-ef fort technology, not a guarantee, meaning more work has to be done to define QOS, he says.
Testing data via CDMA is more complex than testing services via IP, Nitschke says.
Bell Mobility of Canada has done a lot of work to understand the different data applications and the characteristics of the traffic via its CDMA network. "Testing has always been a priority because it is always a learning experience to learn about new ways to optimize a cluster of cells," says Bruce Rodin, director of technology for Bell Mobility. "It has not been fundamentally changed by data."
As the network moves toward the next generation, Bell Mobility does not foresee much change in TAM because advanced technology-1XRTT in this company's case-will allow data and voice to be treated separately, Rodin says. "Our experience shows that the network's frame error rates in voice are more than capable of sustaining the same for data."
Because IP traffic travels on six or seven protocol layers, others maintain that protocol testing will remain necessary to ensure quality of voice and data. QOS testing becomes much more critical because of the different layers involved with IP, Radousky says.
Monitoring the competition
Carriers also should be aware of how the infrastructure works with the services going over their networks. Therefore, for some, a data collection process will help verify the overall health of the network. This is where a company such as Safco Technologies enters the picture.
"We allow the carrier on the planning side the ability to simulate the effect that a lot of services will have on the network," says Biju Nair, vice president and general manager of software products for Safco, which was recently acquired by Agilent. "Carriers do not want to deploy a data network by damaging the voice network."
The company's Recon Wireless Market Reports offer carriers a picture of their market position. In addition, carriers can get a view of competitors' networks. The company's engineers perform network performance analysis and evaluations that describe how the subscriber perceives carriers' service and that of competitors', which also is included in the reports.
Safco's Wizard networkplanning tool, a Windows-based package that includes prediction plots to aid network growth planning, interference analysis and multi-technology deployments, includes RF modeling capabilities and terrain-based propagation model analysis for wireless technologies. "[Network testing and maintenance] have become a priority over the last five years as the number of carriers has doubled and even tripled," Nair says. "It is one of the only ways to keep revenue up and increase minutes of usage."
Testing has been important from a voice perspective, but "a data network will add a bigger urgency for the carrier to make sure there are good services," Nair says.
It's not all about data...yet
Most everyone realizes that the data revolution will increase the need to test wireless networks-But data is not the only thing demanding attention from test companies.
Roaming, for one, is still a significant test point. It will continue to be a challenge as data becomes more prevalent. This is why Tekelec considers it important, says Dan Bantukul, senior product manager with the company's velOSity product group.
"Roaming can impact a carrier's revenue due to dropped calls," he says.
At this point, the company considers this more of a priority than packet traffic because packet traffic is still in its infancy. "As far as packet traffic is concerned, we are not sure where it is going," he continues.
Tekelec is not alone in this opinion. "Nobody knows what is going on with data, and though it will be here, it is not here yet," says Chuck Forrest, general manager of the wireless test group at Ameritec.
Although Ameritec's wireless group intends to provide the ability to measure QOS in data transmission by the fourth quarter, it has not determined what form this will take. "We are not sure about the look of the equipment, but it will need to have a reasonable system to measure QOS on data transmission irrespective of the technology on the wireless network," Forrest says.
To test the performance of voice traffic via wireless networks, Ameritec transports packetized information. Initially the company's PC-based system sends voice over a wireless link to assess quality. It then puts the phone in data mode to test the data sequence. The output, after going out via the wireless network to the subscriber unit and back, consists only of the voice parameters. But because the company has to look at the packets, it believes this is a small step toward establishing an effective packet-traffic testing solution for carriers.
"We internally take a hard look to analyze the packets and the information that is, at this point, reporting on voice quality" says Charles Alleyne, systems program manager with Ameritec. "We are looking at the success rates of these packets over the network."
The company currently works with carriers with its Subscriber Wireless Automated Remote Measurement system product, or SWARM, which provides a real-time, centralized collection of cellular or PCS coverage, subscriber QOS and infrastructure performance data using virtual subscribers (Figure 1).
The fact the company might have an upper hand because it monitors the transport of packet-based information has given it a confident outlook as third generation approaches. "We will have more test solutions, probably well before there is a lot of data being transferred out there," Forrest says. It is difficult heading into a technology that is like a great unknown, he says. "We do not even know how many people will buy [high-speed wireless data services] at all."
The 3G hurdles
Although 3G specifications still are evolving, equipment providers have been moving forward in terms of wireless data R&D. Wireless data brings added dimensions such as an increased need for speed and reliability, which will affect QOS assurance. Speed will be most important when it comes to wireless Internet applications because many consumers have become accustomed to receiving content via a T-1 connection at their PCs. Therefore, wireless will end up playing catch-up with wireline service, says Safco's Nair.
"I cannot imagine what it will be like when 3G comes around," he says. "it will be a monumental thing to manage because the industry has been living easy for the past 15 years with just voice services."
As 3G standards remain in flux, T&M companies and carriers play the waiting game, doing what they can to prepare for the next generation. "If the standards body cannot finalize what implementation to use, there will be problems in the operator world," says Tekelec's Bantukul. The company is aiming to have a 3G service trial by 2001 or 2002.
"With the shift to 3G, the transport will change from being circuit-switched to packet-switched, which [will require] different compression techniques because the characteristics of the transport are so different," he says. Today the company's velOSity products work together to test different parts of wireless networks (Figure 2). "Like Microsoft with its different products that all work on a common operating system, with each component sharing information with the other, the same concept applies to velOSity," Bantukul says.
For example, if the carrier initially needs a universal mobile telecommunications system (UMTS) testing solution, it first can purchase that and then add other solutions on top of it later. That's because, along with UMTS, the underlying operations system might have to have SS7 and IP telephony solutions connected to it. "Customers can have an integrated platform that shares the same testing paradigm, learning one test at a time," Bantukul says.
QOS will remain a prime goal of operators. The new 3G mobile networks will have broadband and IP and worldwide roaming on them, making QOS less of a guarantee at first. Presently, wireless data has not had a large impact on cell site equipment because they already are set for digital. Whether it is data or compressed voice traf fic, the test equipment does not care, says BellSouth's Radousky.
However, as the carrier transitions to enhanced data rates for GSM evolution technology "things will be different, and the hardware is not ready yet," he says. "We are still in the planning stages, and vendors are champing at the bit to get stuff out ahead of the curve so that we can buy it."
While there is a high level of concern over what it will mean to maintain a high level of QOS, Agilent, which prides itself on having a data-com test group, has been fielding questions from carriers about how to become more data-centric.
"To date we have focused on wireline, but now we are trying to marry what we know into wireless," says Agilent's McHenry The company, which currently is just in discussions with carriers because many are beginning trial launches, has been demonstrating what traffic models worked in wireline.
"The level of quality that will be required in a network for data will most likely depend on what applications are running over it," McHenry says. "It will be important for them to understand what types of traffic they will be doing."
For BellSouth Cellular, there are two distinct types of testing: testing the hardware and simulating the customer experience on the network, Radousky says. Although the company still is in the planning stages and has yet to deploy packetized data, it currently offers circuit-switched data up to 9.6 kb/s. To test the circuitswitched flavor of data, the carrier fires up a WAP-enabled phone and places a call via its GSM network.
"We just put the phone in test mode and get the diagnostics from the phone," he says. "The area we are trying to optimize is speed of connection to the Internet, and the phone is a critical tool for testing data."
In terms of 3G, BellSouth Cellular waits with the rest of the industry "Equipment vendors are trying to make test equipment, and they need test protocols from test companies," Radousky says. "Our goal is not to buy elaborate test gear and hire more people to maintain it. We believe vendors should give us equipment that is easy to maintain, with internal diagnostics taking care of the rest."
The carrier intends to deploy its data network in six to nine months.
The great wide open
The lack of a definite standard, no doubt, has created frustration during the industry's high-speed data transition.
Perhaps progressing in stages-first generation, 2.5G and finally 3G-will enable the finished technology to be introduced with a bang and not a bust. Whatever the reason, carriers and T&M companies continue to explore how wireless networks must evolve for packet data and how together they can ensure QOS.
Two entities such as Internet technology and wireless communications could not have been expected to converge without a lot of pain. And they will not blend successfully for the consumer without innovative data applications and a network that can deliver quality.
"If we just addressed the data portion, it would not be complex. The complexity is in the combination of the Internet and the wireless world," says Tektronix's Nitschke. "Operators have to look at the network from a different point of view and consider if it can handle it all."
Copyright PRIMEDIA Intertec May 29, 2000