Heading for 4G: WiMAX and LTE

By Richard “Zippy” Grigonis

Whether you call it Personal Broadband, Mobile Broadband, or the Mobile Internet, both WiMAX (Worldwide Interoperability for Microwave Access) and LTE (Long-Term Evolution) are about providing broadband access on-the-go. WiMAX and Mobile WiMAX (802.16m) is an open specification from the IEEE, the same folks who brought you WiFi. LTE, with its somewhat higher bandwidth, is emerging from the 3GPP world of proprietary technologies (indeed, LTE can co-opt existing 2G and 3G spectrum as well as new spectrum), though there are efforts underway to make it more “open” if not more expensive to deploy than WiMAX.

WiMAX and LTE have been portrayed as competitors, with Sprint and Intel lining up on one side to champion WiMAX, and Verizon Wireless, Ericsson boosting LTE on the other (companies such as Motorola have an interest in both technologies). However, this is an overly simplistic view of the situation.

Alvarion practically invented WiMAX. It remains the world’s leading provider of innovative WiMAX and wireless broadband network solutions, with more than 3 million units deployed in 150 countries. Alvarion’s product portfolio encompasses the full range of frequency bands, with both fixed, nomadic and mobile solutions designed to enable the delivery of personal mobile broadband, business and residential primary broadband access, corporate VPNs, toll quality telephony, mobile base station feeding, hotspot coverage extension, community interconnection and public safety communications.

Alvarion’s Ashish Sharma, Vice President of Corporate Market Development, says, “We’re one of the founders of the WiMAX industry, we got going even before the WiMAX Forum came into existence, or which we are a founding member. We saw a clear need in the marketplace for WiMAX, which would do for broadband what cellular technology did for Voice – make it ubiquitous, personalized, and easily transportable. That was our vision. You couldn’t do it with legacy 2G and 3G technologies because of their bandwidth limitations. For example, 3G is based on narrow channel widths. We figured that the channel size should be expanded greatly, and on top that there should be a wireless broadband radio interface such as OFDMA [Orthogonal Frequency Division Multiple Access] which is more spectrally efficient, so it allows you to send much more data than competing technologies such as WCDMA [Wideband Code Division Multiple Access] or UMTS [Universal Mobile Telecommunications System] cellular 3G. Consumers can now have a personal wireless broadband connection that they can carry with them in the form of a laptop, small screen devices such as MIDs [Mobile Internet Devices], UMPCs [Ultra Mobile PCs] or it could be something like an iPhone.

“Our second vision was to provide plain broadband connectivity in many underserved areas such as dialup and developing markets,” says Sharma. “In Europe, for example, there are still areas that lack a broadband infrastructure. WiMAX is ideal for such situations, because it gives you a very good business case, as opposed to having to dig cables in the ground, which is what’s required by the fiber technologies. There are now more than 400 commercial WiMAX deployments, and we have been involved with more than 240 of them. We continue to see lots of demand, both in terms of the connectivity and personal broadband applications.”

And now other technologies such as LTE are slowly coming along, but LTE is very similar to WiMAX, but with a larger bandwidth,” says Sharma. “Both WiMAX and LTE will coexist because the way a lot of the mobile operators do broadband is very different. Their definition of data is different from that of DSL and cable providers. 3G broadband is essentially narrowband so users can download clips. They’re downloads – it’s not like full streaming, high-speed Internet access. That’s not their business model. But WiMAX was designed from the ground up to provide full broadband Internet access, just like you have it at home or in the office. I don’t believe that LTE is really targeting that market,” says Sharma. “LTE focuses more on downloads on-the-go. With WiMAX, we target everything from cameras to anything that today has WiFi embedded in it. Tomorrow they will have WiMAX embedded in it, thus extending the reach of access to the Internet and the many Web 2.0 applications residing there.”

Wrist-Slapping the Incumbents

Aptilo’s sophisticated wireless service management platforms are designed for service providers, enterprises and municipalities who need rapidly deployable, scalable multiservice solutions to quickly manage data and voice services over WiMAX, Metro wireless and WiFi networks.

Torbjörn Wård, CEO of Aptilo, “Before founding Aptilo in 2001, I had worked at Ericsson for 12 years. I remember the ‘fights’ between CDMA and TDMA, and then CDMA against GSM. There’s always a fight to pick, and it looks like something like that will occur between WiMAX and LTE. But it’s good to have a external enemy – it keeps people on their toes. Thus far, GSM has been a ‘winner’ in terms of sheer numbers, though there are hundreds of millions of CDMA users. When people ask me whether WiMAX or LTE will be a ‘winner’ I generally respond that, when it comes to broadband, it’s been provided by either cable, DSL or now fiber. I in turn ask these people, ‘Which of these three do you think is the winner in broadband?’ People then look at me and frown, saying, ‘There are simply different technologies for different operators and markets.’ And my argument is that there’s a roughly equivalent situation involving WiMAX and LTE. For an operator running GSM or 3G, obviously they’re sticking with their existing roadmap and are working on the evolution of their GSM and 3G networks, even though ‘evolving’ to LTE is more like a forklift upgrade. But they’re sticking to that path because even their equipment suppliers are working on it. Moreover, they have the licenses and are thus more prone to get licenses for LTE, whereas with WiMAX operators, there could be cellular operators with WiMAX licenses, but in most cases these comprise many different kinds of operators. There are wireline operators, telcos, cable companies, greenfield operators delving into WiMAX. There’s greater diversity with WiMAX.”

“If you look at Asia, which is one important market for WiMAX,” says Wård, “several countries have said that, from a political and legislative perspective, ‘We are not satisfied with the competition in broadband and wireless broadband. It’s not good enough and it’s not expanding fast enough.’ These operators see the political, financial and general economic gain of having people connected to broadband. They have goals for broadband penetration. In some countries, such as Malaysia, they’ve said, ‘We will not give 2.5 gigahertz licenses to the existing telcos or cellcos, even though there are four of them here in Malaysia. They have their 3G platforms. Instead, we will give about five WiMAX licenses only to companies that are new. They directed the licenses away from the incumbents, because they felt there needs to be many more ways of providing broadband, and you established guys aren’t going to be fast enough in your deployments. So, it’s a way for a government to slap operators on the wrist and say ‘You haven’t really performed well and so you won’t get the chance for the new licenses’. I see this kind of thing occurring in a number of countries. Sometimes, out of five or six WiMAX licenses, only one or two will go to the incumbents.”

“Of course, in places such as India, they don’t even have 3G,” says Wård, “so cellular operators are definitely interested in WiMAX there.”

“There are really two WiMAX value propositions,” says Wård. “First is what Sprint/Nextel is doing, which puts WiMAX head-to-head with LTE or 3G turbo, or HSDPA, or EVDO. It’s about wireless broadband, the promise of mobility and functionality on many devices. The second value proposition essentially involves providing broadband – period. It just so happens that wireless is a good way of doing this when you don’t already have cables buried in the ground.”

Playing Both Sides

Cisco offers a complete end-to-end broadband wireless solution featuring the best-in-class Mobile WiMAX technologies, which are tightly integrated with Cisco’s IP NGN transport and service delivery infrastructures. Cisco’s Kittur Nagesh, Director of Marketing in the Service Provider Marketing Segment, says, “There is some confusion, some of it unwarranted, regarding the positioning of WiMAX and LTE, sometimes placing them in opposition to each other like a boxing match. The context for all of this is what’s happening with the mobile Internet. In the last 10 years, new Internet applications have driven the need for high performance data delivery. Mobile operators have gone well beyond mobile voice, offering various applications, such as SMS that have become pervasive. But as we go forward, the data and application-driven aspects of the mobile Internet will increase even more profoundly, and will enable richer applications, both for productivity and collaboration on the business side, or infotainment on the consumer side. The radio networks, which were largely handling mobile voice are now in the process of adapting to these high performance applications. There is a mutual positive feedback between the two. New bandwidth-hungry applications force the development of new RANs [Radio Access Networks] and personalization, while additional bandwidth encourages its use.”

“From a Cisco standpoint, these new radio technologies such as LTE or WiMAX, or even the existing 3G technologies as HSPA or EVDO, are all enabling a new wave of applications which will call for exploiting the virtues of IP networks from end-to-end,” says Nagesh. “That’s good for us, be it LTE or WiMAX. We have enabled new kinds of networks over the past 10 years through our product portfolio for routing, switching, gateways, service engines, application awareness, deep packet inspection, and so forth. They help bring these capabilities with the notion of personalization and billing flexibility, so that there’s a win-win ecosystem. The underpinnings of all this are IP networks. So we’re exciting that what some people call 4G networks, such as LTE or WiMAX are on the move. WiMAX is already here, while LTE trials start in 2009, with roll outs occurring perhaps in 2010, 2011 or 2012.”

“Regardless of when large-scale LTE adoption occurs,” says Nagesh. “It’s fair to say that end-to-end high performance IP architectures and solutions will drive the next wave of the Mobile Internet, which in itself is good for the ecosystem and for Cisco, since we can build on our strengths and can extend our portfolio of gateways, content service engines, and so forth to adapt to and serve the needs of these high performance networks.”

“Also, if you believe that the Mobile Internet data explosion will continue, then there are obvious radio aggregation ‘choke points’ that will be alleviated by Carrier Ethernet type services and high performance cell site routers that will become the norm. The many handsets and other devices are now pumping so much data into the network that the scalability and performance aspects of the technology has become extremely important, because we do believe that in the mobile Internet world, some providers and operators will exploit it successfully and make money, and others might actually ‘bite the dust’. So in some sense we’re talking about a market inflexion for how operators and service providers capitalize on this phenomena, adapt, and build the appropriate infrastructure, intelligence and personalization. The segmentation will be so microsegmented that it will all become a matter of the network doing things for particular individuals, rather than similar groups. So there is the possibility of capturing ‘long-tail’ markets in a nicely-architected end-to-end IP system if there is sufficient intelligence operating in the network.”

Different Strokes for Different Folks

Juniper Networks, Inc. a major player in high-performance network infrastructure equipment, Mallik Tatipamula, Head of Wireless/Convergence says, “Everyone debates whether WiMAX and LTE are competing or complementary technologies. In the 2.5G and 3G world, GSM took one path and CDMA another. They have fundamentally different modulation schemes. When it comes to WiMAX and LTE, however, the good thing is that both of them harmonize on a single OFDMA modulation scheme, although there are some minor differences in terms of which MIMO [Multiple-Input and Multiple-Output] scheme each technology uses in the physical layer. But fundamentally, the bottom line is that OFDMA is used, so there is some commonality. And when it comes to IP, both WiMAX and LTE are all IP-based technologies. They are both distributed and ‘flat’ architectures. Again, this is unlike either the GSM or the CDMA approach – GSM/UMTS employing the ATM architecture and CDMA2000 being IP-centric.”

“WiMAX is a standard coming from the IEEE, which happens to be a more open architecture than LTE, which comes from the 3GPP world which is more of a controlled, walled garden approach that’s trying to evolve toward more openness. It’s the classic clash of the data and telecom worlds.”

“In terms of penetration and/or adoption, there are three major camps,” says Tatipamula. “The first is an ‘LTE-only’ camp. The second is a ‘WiMAX-only’ camp. We’re now starting to see a third camp, where operators are adopting both technologies. Take for example, the operators in Asia PAC. We’ve heard that many of them are not only going to adopt LTE as their next-gen 4G technology, but at the same time they are deploying WiMAX too. Europe is very much LTE-centric. However, we are seeing demand for WiMAX in Taiwan and in many emerging countries, especially the Middle East, Africa, and India. We see more demand in WiMAX in developing/emerging countries where they have very little or no wireline infrastructure. Fixed WiMAX allows a quick way to provide residential broadband services.”

“That in turn brings up the related question of Mobile WiMAX versus LTE,” ays Tatipamula. “There are multiple camps. ‘The one should be looking at is where operators are adopting both WiMAX and LTE together. That’s very interesting, because we should examine how they expect each technology to be used by segments of their customer base. LTE with its higher bandwidth is seen as suitable more for mobile TV and music downloads, along with any laptop connectivity on-the-go via an external card. At the same time, however, the operators want to expand the mobility market with some innovative customers solutions by having WiMAX enable visual-centric portable data devices, relying on embedded or external cards. They’re also looking at having WiMAX embedded and external cards used in visual-centric handsets, or in SOHO broadband tenant applications. There’s also the possibility of using WiMAX in some consumer electronics, such as cameras, camcorders and so forth. So there are slight variations in terms of applications when comparing WiMAX and LTE. Operators are positioning these technologies for different application needs.”

“So we believe that both WiMAX and LTE will co-exist in certain regions, and that operators will use WiMAX for one set of applications, and LTE for another.”

Companies mentioned in this article:

Alvarion
www.alvarion.com

Aptilo Networks
www.aptilo.com

Cisco (News - Alert) Systems
www.cisco.com

Juniper Networks
www.juniper.net

Richard Grigonis is Executive Editor of TMC’s IP Communications Group.

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