Toolkit: Tutorial: Comparing Wireless Broadband Technologies for the Enterprise Campus

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1 Gartner for IT Leaders Publication Date: 22 September 2006 ID Number: G Toolkit: Tutorial: Comparing Wireless Broadband Technologies for the Enterprise Campus Robin Simpson Since early 2005, colleges and universities worldwide have been among the first organizations to deploy large-scale based Wi-Fi mesh networks to provide Internet and intranet access for their students and staff. As in business, the laptop has become an important student tool in many educational institutions, with applications including online access to course materials and research, audio and video streaming of lectures and tutorials, distribution and submission of assignments via , and collaboration among students and staff. However, as in business, voice remains the No. 1 mobile application for personal and academic use. Because most students today arrive on campus with their own mobile phone, some institutions have also begun to provide infrastructure to improve cellular coverage in-building and across the campus. The same technologies can be applied to almost any kind of large business or government precinct with outdoor and indoor areas from head offices or factory complexes to shopping malls, city halls and airports. Key Findings Businesses face the same mobile application, work-style and infrastructure issues as colleges and universities, so they should study the campus wireless network design and deployment lessons learned by those institutions. A single network technology fixed or wireless cannot satisfy all campus mobile connectivity needs. A hybrid network will be required for the foreseeable future. Enterprises should consider partnerships with public infrastructure operators for largearea campus deployments to minimize capital and operational costs especially for voice services. Enterprises that own or control their buildings and campus surroundings have two things every wireless operator wants: real estate for antennas and base stations, and right of way for backhaul two valuable commodities when building a wireless network. Predictions WiMAX will not be a viable campus Wi-Fi backhaul technology until WiMAX will not be a viable mobile wireless broadband access technology before Reproduction and distribution of this publication in any form without prior written permission is forbidden. The information contained herein has been obtained from sources believed to be reliable. Gartner disclaims all warranties as to the accuracy, completeness or adequacy of such information. Although Gartner's research may discuss legal issues related to the information technology business, Gartner does not provide legal advice or services and its research should not be construed or used as such. Gartner shall have no liability for errors, omissions or inadequacies in the information contained herein or for interpretations thereof. The opinions expressed herein are subject to change without notice.

2 Recommendations Supplement your fixed wireless LAN with a wireless WAN and wireless mesh network strategy for campus mobile broadband. Use wireless LAN or wireless mesh for short-term or temporary campus wireless deployments, such as open days, conferences and sporting events and use the experiences gained to plan permanent installations. Publication Date: 22 September 2006/ID Number: G Page 2 of 7

3 ANALYSIS The Technologies Available for Campus Wireless Wi-Fi technology conforming to at least the b and g standards is built into almost every enterprise laptop today, and an increasing number of enterprise-class PDAs and cell phones, as a low-cost or no-cost option. Thus, from the point of view of the end user at least, it is an ideal low-cost network access technology. However, Wi-Fi is not the only choice for the campus network infrastructure itself, particularly if coverage of a large geographic area is required Wi- Fi mesh, WiMAX, proprietary wireless broadband access or even 3G cellular networks may all have a place. Comparing the Available Technologies for Access and Backhaul Table 1 shows the wireless broadband technologies that can be used for campus deployment. Table 1. Wireless Broadband Technologies for Campus Deployment Technology Strengths Weaknesses Future Fixed Wi-Fi LAN ( a,b,g) Low-cost consumer premises equipment (CPE) for b and g now included in many laptops PC Card CPE available Low-cost infrastructure Relatively easy and fast to deploy "Free" industrial, scientific and medical (ISM) band spectrum Strong standards and very competitive vendor market Ideal for access Useful for backhaul and bridging a good for capacity and channel management High, symmetrical bandwidth Data usage is free within the campus network Limited range (100 m) Not very scalable to large networks No standards-based roaming No cell-to-cell mobility Limited channels for b and g a has channel or licensing issues in some countries The 2.4GHz ISM band used by b and g is prone to interference from other Wi-Fi networks, or from consumer technologies like Zigbee or Bluetooth Battery and processor hungry at higher bandwidths Access point capacity can limit voice capacity n standard, when agreed, will support greater than 100-Mbps throughput may be overshadowed by WiMAX at least for backhaul and outdoor coverage of large areas Publication Date: 22 September 2006/ID Number: G Page 3 of 7

4 Technology Strengths Weaknesses Future Wi-Fi Mesh ( plus proprietary extensions) Low-cost CPE for b and g now included in many laptops PC Card CPE available Low-cost infrastructure that is highly scalable to large areas Easy and very fast to deploy "Free" ISM band spectrum Ideal for access and backhaul b, g can be used for access along with a for mesh backhaul High, symmetrical bandwidth Data usage free Proprietary IEEE s mesh standard still under development Single vendor lock-in for supply and support No guarantee that vendors will support eventual s standard No standards-based roaming No cell-to-cell mobility The 2.4GHz ISM band used by b and g is prone to interference from other Wi-Fi networks, or from consumer technologies like Zigbee or Bluetooth Battery and processor hungry at higher bandwidths Voice performance can be poor because multihop mesh backhaul architecture leads to congestion and latency issues WiMAX may be used for Wi-Fi Mesh backhaul, with Wi-Fi used for access may be overshadowed by WiMAX, at least for backhaul and outdoor coverage of large areas 3G Cellular (wideband code division multiple access [WCDMA] and code division multiple access [CDMA] 1xEVDO) Wide range of PC Card CPE and mobile terminals available Increasing numbers of vendors offering laptops with built-in PCI Express 3G CPE Uses operator-owned infrastructure (no capex) Excellent range (5~20 km) means coverage likely to be better than Wi-Fi Provides high-quality voice as well as data Battery efficient Full mobility, including cell-to-cell handoff at vehicular speeds Relatively expensive CPE Asymmetric, relatively low bandwidth ( Kbps) Coverage may be limited to high-population-density areas Requires operator to buy expensive licensed spectrum Expensive for data usage unless you get a "flat-rate" contract Even then, "fair-use" data limits may be an issue Premature laptop obsolescence if not firmware upgradable to High Speed Packet Downlink Access (HSDPA) and High-Speed Uplink Packet Access (HSUPA) Most PC vendors will include built-in PCI Express 3G CPE The next evolution of 3G called HSDPA will bring data rates of 300-Kbps uplink and 2- to 3-Mbps downlink by 2007 HSUPA will lift uplink speeds to 1 to 2 Mbps by G Long-Term Evolution (LTE) will bring data rates of up to 100 Mbps but may not be deployed until 2012 or later Publication Date: 22 September 2006/ID Number: G Page 4 of 7

5 Technology Strengths Weaknesses Future Mobile WiMAX ( ) Time Division, Code Division Multiple Access (TD-CDMA) and Proprietary WBA (Examples include iburst, IP Wireless, Navini, Flarion, Soma) Source: Gartner (September 2006) 2- to 10-Mbps bandwidth, symmetrical at option of operator Highly scalable Base stations much less expensive than cellular or proprietary wireless broadband access (WBA) Excellent range (5 to 20 km) Very competitive vendor market Full mobility, including cell-to-cell handoff at vehicular speeds Ideal for backhaul and for access by 2008 Typically 1-Mbps asymmetric bandwidth Scalable Excellent range (5 to 20 km) Full mobility, including cell-to-cell handoff at vehicular speeds Battery efficient Available now, wellestablished and proven in commercial deployment Ideal for access No mobile CPE and terminals available yet Mobile WiMAX certification process has not begun Requires operator to buy expensive licensed spectrum Battery efficiency not known yet Not available yet, relatively unproven in commercial deployment Relatively expensive base stations Limited choice of CPE and terminals, usually from only one vendor Will likely follow the same path to commoditization as Wi- Fi, including effectively free CPE in laptops by 2009 Likely to be a common public infrastructure by 2010, but not ubiquitous Bandwidth will steadily increase Ideal for access once CPE costs approach zero Window of opportunity until mobile WiMAX is ready for widespread commercial deployment in 2008 Future will depend on finalization of the IEEE standard for mobile wireless broadband Why Not Go All-Wireless Now, Both In-Building and Outdoors? With the current hype about Wi-Fi and WiMAX, many clients planning new purpose-built offices, office moves or refurbishments have asked us whether they should avoid installing fixed wires altogether by deploying all-wireless network access. Despite recent advances, our advice remains the same: Enterprises will need both fixed and wireless infrastructure for the foreseeable future. It is certainly true that, as work becomes more mobile, there will be more and more demand for wireless connectivity in our offices, but the fact remains that wired infrastructure will provide the best price/performance for the near future, fundamentally because wireless is a shared medium. End users who today enjoy 100-Mbps or even 1-Gbps fixed network connectivity at their desktop will be very disappointed if they become one of 10 people sharing the 54-Mbps (or even 108-Mbps) theoretical total throughput of a typical access point. Even if 90% of enterprise applications work satisfactorily with the bandwidth delivered by wireless, most organizations will have some desktop applications that demand greater bandwidth or quality of service. A few simple examples include: Publication Date: 22 September 2006/ID Number: G Page 5 of 7

6 Media-rich interactions, such as videoconferencing or virtual collaboration. The limited latency and aggregate throughput of wireless even today means you can only get six to 10 simultaneous voice sessions into an access point. It is unlikely that a wireless access point could support more than one or two simultaneous videoconferences. File transfer tasks, such as backing up the 60GB disk on a desktop or laptop. Such intense traffic generated by a single user badly degrades the performance of a shared network designed to cope with shorts bursts of traffic from multiple users. Applications using large datasets, such as computer-aided design, geographic information systems, video editing, high-resolution digital photography and digital publishing. Thus, most office environments will need wires and fiber as well as wireless for the foreseeable future. RECOMMENDED READING "Toolkit: Checklist: Choosing Wireless Broadband Technologies for the Enterprise Campus" "Cell-Fi Handsets Not Yet Ready for Mainstream Business Use" "3G Wireless Notebooks Will Be a Futile Gold Rush" "Distributed Antenna Systems Support Enterprise In-Building Wireless Strategy" "When Wireless Broadband Makes Sense for Enterprise Use and the Available Technologies" Acronym Key and Glossary Terms 3G CPE Cell-Fi WBA Wi-Fi WiMAX Wireless Mesh WLAN The third-generation cellular wireless networks, which support increased voice capacity and peak data speeds up to 2 Mbps in fixed locations and up to 384 Kbps at pedestrian speeds. Consumer premises equipment the hardware interface to the network; for wireless networks, typically a built-in wireless modem or PC Card wireless modem. A dual-mode mobile terminal that includes two radios: one for connection to cellular voice networks and one for connection to Wi-Fi networks. Wireless broadband access a generic term for broadband access using any wireless technology. Wireless Fidelity certification by the Wi-Fi Alliance of a, b or g standards compliance and interoperability. Worldwide Interoperability for Microwave Access broadband wireless technology based on the IEEE standards. A mesh topology network based on Wi-Fi standards but typically linked together by proprietary extensions today. The Wi-Fi Alliance Task Group s is developing a proposal for consideration as an IEEE standard. A network that connects devices or LAN segments using radio (the unlicensed 2.4GHz and 5GHz bands), instead of physical cables. Publication Date: 22 September 2006/ID Number: G Page 6 of 7

7 REGIONAL HEADQUARTERS Corporate Headquarters 56 Top Gallant Road Stamford, CT U.S.A European Headquarters Tamesis The Glanty Egham Surrey, TW20 9AW UNITED KINGDOM Asia/Pacific Headquarters Gartner Australasia Pty. Ltd. Level 9, 141 Walker Street North Sydney New South Wales 2060 AUSTRALIA Japan Headquarters Gartner Japan Ltd. Aobadai Hills, 6F 7-7, Aobadai, 4-chome Meguro-ku, Tokyo JAPAN Latin America Headquarters Gartner do Brazil Av. das Nações Unidas, andar World Trade Center São Paulo SP BRAZIL Publication Date: 22 September 2006/ID Number: G Page 7 of 7