The Case for Broadband
Wireless Connectivity
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Contents
Executive Summary 1
The Business need for high-speed connectivity 1
Typical Broadband Wireless Use 3
Wired connection options: their benefits and tradeoffs 4
Executive Summary
This white paper explores the options open to executives and networking professionals in public and private enterprises who seek high-speed building-to-building connectivity solutions for their campuses and remote locations, but who are also constrained by real-world budgets. It reviews the most popular leased line options including DSL, T1/E1 and fiber optic cable, as well as wireless LANs. And it delineates the advantages of broadband wireless connectivity, a solution that is finding greater acceptance due to its high capacity, ease of installation, and low cost.
The business need for high-speed connectivity
Businesses and other large organizations require continuous high-speed data connections in order to function effectively in today’s fast-paced environment. This need for high-capacity communication will continue to grow for several reasons. First, applications that had been considered high-end or esoteric are finding increased use in businesses to the point that they will soon become “must haves.” The most important of these are applications using multimedia including video and/or audio. Presentation software is incorporating sophisticated graphics and multimedia for their impact and ability to quickly communicate complex information.
Second, while most businesses have networked the computers within any given facility there is a clear need for enterprise-wide networks that connect buildings and campuses within a city or region. It makes no sense to have instant access to information within a building but to end that free flow of information at the building walls. High-speed data connections allow all departments and groups, regardless of physical location, to share information in real time.
Third, video conferencing is gaining support. “Virtual meetings” allow more team members to interact while minimizing time away from the office. Efficiency is maximized. The connection option that makes this possible and affordable across campuses and metro areas is often a point-to-point broadband wireless link.
Fourth, Internet traffic has increased exponentially. Customers routinely use web browsers and web-based communication, creating considerable traffic. Email with large presentations and files clogs small pipe
connections. Files of all types are increasing in size to the point that sending and receiving data over a modem connection is simply too time consuming. Business decisions can’t be put on hold while data is being transferred over 56Kbps dialup lines.
Fifth, emerging IT practices such as network storage and networked backups require large data pipes. Networked storage involves Network Attached Storage (NAS) as well as Storage over IP (SoIP) where storage resides on the network. Network backups provide cost savings by allowing one large tape device located in one building to back up the servers found in multiple buildings. Finally, providing a redundant connection to protect the network against disasters is another important application that requires high-speed connectivity to function reliably and efficiently.
Broadband’s Last Mile Dilemma
The move to “big pipe” connectivity is inevitable, but the promise of broadband has foundered on the obstacles encountered in connecting individual desktops and LANs to one another and to the Internet. This is often called the “last mile” problem, i.e., it is relatively easy to send information across country via high-speed fiber optic networks, but difficult to extend that speed from the network hub to the user.
Business managers and executives are frustrated by the situation because high-speed connection has progressed from being a luxury to being a business necessity. Files sent between business units are increasing in size due to richer content such as high resolution graphics, sound—including telephony and video. Instantaneous high-speed data communication is vital to many business functions from Customer Relationship Management (CRM) to Supply Chain Management (SCM) to Enterprise Resource Planning (ERP) to data warehousing.
Wired solutions—slow to deploy, expensive to maintain
Businesses have several connection options available. Unfortunately, most wired solutions take weeks, and sometimes months, before service is available to users at the desktop. About 90% of US businesses do not have access to fiber optic lines, so that means trenching, tedious permitting, and resolving right of way issues— resulting in long delays and great expense—if fiber is selected as the connection medium. Leased line solutions utilizing T1/E1 lines or DSL connections run into other installation delays and leased-line providers often impose excessively high monthly fees for the connection.
Broadband wireless—high capacity, low cost
For many companies,governmental/educational institutions, and ISPs the answer to the broadband dilemma is to install high-capacity broadband wireless bridges from point to point, and from a single point to multiple sites. Typical
installations connect buildings and/or campuses to each other, LANs to WANs, and points of data aggregation to the Internet backbone. Wireless connections offer significant
cost savings because there are no monthly fees to pay. Once you purchase and install the equipment, you are freed from the monthly expense of renting your connectivity. And because the installation is simple the system can be up and running within days.
Typical broadband wireless use
Businesses, governmental/educational institutions, healthcare organizations and ISPs are all heavy users of broadband wireless data connections.
Broadband wireless is rapidly gaining market share because it brings the high-speed connectivity to users quicker, easier, and less expensively than other solutions. It makes “backbone everywhere” service a reality. High-speed connections need not be limited to a small group of organizations that can afford the high cost and are located in an area served by fiber cable or one of the leased line alternatives. Wireless leapfrogs those obstacles.
In short, any organization that relies on IP/Ethernet data communications can immediately benefit from
broadband wireless. And because of the rapid adoption of bandwidth-hungry applications, “immediately” is none too soon. IT managers are reporting increased demand from their internal customers for applications using video, voice and large file transfers. Those customers expect to be able to use such applications right away. In addition, competitive factors are forcing the adoption of these applications now rather than putting them on hold. All of these user and business demands are easily accommodated by broadband wireless.
Tsunami MP.11
Inexpensive redundancy
Any one connection is vulnerable to interruption. Most business managers recognize the need for 100% network up time for their mission-critical applications. Broadband wireless provides an inexpensive means to achieve redundancy that preserves network connections. The cost of a broadband wireless connection is cheap insurance to protect the investment of time, man-hours, and capital made in networking. Even if fiber lines are severed due to utility work, street construction, natural disasters, or other factors, wireless can maintain the lifeline between departments, buildings, and offices. A dramatic, albeit tragic, example is that of organizations in Manhattan, New York that were able to maintain communications following the September 11, 2001 terrorist attacks in the United States because of wireless redundancy and quick redeployment.
Wired connection options: their benefits and tradeoffs
Businesses and institutions have several connection options. The choice of connection will depend on factors that include cost, time to deploy, and capacity.
Modem connections
A WAN composed of modems connected via PSTN (Public Standard Telephone Network) is the least desirable data networking option for business use. Limited to a 56 Kbps transfer rate, the connection is too slow for broadband use. The best that can be said for modems/PSTN is that the technology is universally available.
Cable modem connections
Cable modems provide relatively high-speed access at affordable rates. They are not, however, suitable for business use for at least two reasons. First, in most cities, cable service is not available in downtown business areas. Second, as more users log on cable service slows, i.e., bandwidth is limited and must be shared by all users online at any one time. The verdict—cable is a home connectivity solution.
Leased high-speed lines
Many businesses with high-speed connections currently use a line leased from the local telephone company. That line can be ISDN, T1 (E1 lines outside of the US & Canada) or DS-3. Leased lines can go virtually unlimited distances and are fast compared to modems but have some drawbacks. One of the most significant of those is the monthly fee to lease the line. Those fees are, in effect, a permanent business cost. In addition, leased-line suppliers tend to be slow to introduce new technology. The solutions they offer may not be the newest or best— imposing an additional competitive “cost” on the consumer. Finally, the speed of these technologies is often insufficient for today’s networking needs.
Another issue with respect to leased T1/E1 lines is delays in installation and implementation. Customer demand is high for these lines and delays of weeks or even months in installation are common. The current infrastructure virtually guarantees a lengthy delay in the installation of broadband connections.
Many analysts thought that DSL would solve the broadband connectivity problems of most businesses. However, DSL too suffers from delays in installation and is limited by proximity to the Telco central office. If your site is more than five kilometers from the central office DSL does not provide a satisfactory connection.
Fiber—speed at what price?
Fiber optic connections are widely acknowledged to provide the highest speed data connections. They are the “gold standard” of the industry. However, fiber comes with its own limitations.
The greatest negative factor to fiber is cost—both of installation and recurring monthly fees. On average the cost to lay fiber ranges from $50,000 per mile on the low end, soaring up to a staggering $500,000 per mile in some cases.
As previously stated, over 90% of businesses in the United States do not have a fiber optic connection. So those who insist upon installing fiber are forced into laying cable. That brings into play considerations such as right of way and permits, as well as the high costs of trenching and laying cable, even if the connection in question is just a few meters from building to building. Plus, like leased T1/E1 lines, leased fiber service, such as OC-3 and OC-12, often require monthly service fees that never go away.
For businesses and institutions located in the suburbs, or smaller population centers, connecting via fiber is even more problematic since the fiber “loop” or backbone is usually confined to downtown business areas. For them, fiber service is simply not available at any price.
Because of the obstacles (both physical and financial) to connecting via fiber cable, expensive leased T1/E1 lines are the default fallback for many businesses. As we have seen, that option is not 100% satisfactory.
Availability for WANs
Throughput
Cost (monthly)
Right of way required?
Distance from POP
Voice Video Data Time to Market PSTN High Very Low Very Low $30 Yes N/A Yes No Yes N/A ISDN Very Limited Low Medium $125 Yes 5 Miles Yes Maybe Yes Very Slow TI Mostly Urban Medium Medium $400-600 Yes 5-20 Miles Yes Maybe Yes Slow DSL Growing (mostly homes) Medium-High Medium $60 Yes 3 Miles Yes Maybe Yes Slow Cable Poor Medium Low $40 Yes 5-10 Miles Maybe Yes Yes Slow Fiber Poor (3%) Very High Very High $3K-15K Yes >100 Miles Yes Yes Yes Very Slow Wireless High High Capital only No up to 40 Miles LOS Yes Yes Yes Fast
Wireless connections—many choices to fit many applications
Wireless connectivity varies in many ways that can affect its use. The principal variations are: • Optical laser connections (Free Space Optics)
• Wireless LANs • Broadband wireless
• License-exempt and licensed (regulated) frequencies
Let’s take a look at the differences between these forms of wireless connectivity.
Optical lasers—a cloudy future
Optical lasers once promised to be an effective alternative to wired connections. They would seem to be the logical “wireless” extension of fiber optic communications; i.e., they use light to connect devices without employing cables to carry the signal. The issue with the technology lies in connection availability over distance. Weather (fog, rain, and snow,) dust, humidity and other environmental conditions far too easily degrade the signal. Because of these limitations, the technology is relegated to less than 500 meter distances. While optical laser technology provides good bandwidth, it is challenged in providing that bandwidth with high availability over distance.
Wireless Local Area Networks—from laptop to LAN
Mobile wireless connections most often involve the IEEE 802.11b, 802.11a and 802.11g standards. In general, the technology is intended to connect individual local devices (such as laptops or PCs) to a LAN. Some have called it the “last hundred feet solution” as compared to the “last mile solution.” 802.11-based networks are the right choice for mobile LAN connectivity, and may be appropriate for building-to-building connectivity where distances are very short and capacity requirements are low. An example where a low-capacity building-to-building
connectivity solution is appropriate is connecting classrooms in an elementary school where computers require under 1 Mbps of data and the buildings are close together. However, for high-bandwidth outdoor connectivity, 802.11-based networks are inadequate. Broadband wireless networks provide the capacity and long-distance connectivity enterprises need.
Broadband Wireless—high speed, low cost, installs immediately
Broadband wireless is a technology that usesmicrowave broadcasting to provide data connections from point to point, or from one point to multiple outlying stations. Among its benefits:
• Very high throughput • No trenching to lay wires • Installation can be accomplished
within 24 to 48 hours
• The cost of equipment and installation can be recouped in as little as 12 months • Unregulated frequency option—no
governmental red tape to slow installation
• Provides inexpensive network redundancy to existing leased lines
• Carrier-class reliability—99.999% availability, or about 6 minutes of network downtime annually
The capacity of broadband wireless systems ranges from 11 Mbps to 860 Mbps aggregate throughput. Such transfer rates are equaled only by fiber connections.
Because no physical connections are required, no cable is laid. This, of course, also means no rights-of-way need to be secured and no permits need to be acquired. That is one reason that installation can be accomplished in just one or two business days.
Although most installations operate over a range of about five to ten miles, point-to-point broadband wireless connections have an effective line-of-sight range of up to 40 miles (depending on factors that include equipment and configuration), so most buildings and/or campuses can be easily linked. In addition, broadband wireless is the most cost effective means to extend existing fiber reach. For example a business with downtown facilities that are linked by fiber may want to connect that network to its suburban campus. A broadband wireless system can link the two networks with a high-speed, no-bottleneck connection at a substantial discount to leased lines.
0 10 20 30 40 50 430 Mbps 100 Mbps 45 Mbps DS-3 10 Mbps 16xT1 8xT1/E1 2xT1/E1 1xT1/E1 4xT1/E1
Wireless Full-Duplex Throughput (license-exempt)
Distance (typical maximum) in miles
Unregulated opportunity (license-exempt vs. licensed frequencies)
Broadband wireless has a significant advantage over other technologies in that some solutions are able to legally operate over unregulated frequencies. In the past, microwave communications have been hampered by the fact that they required US Federal Communications Commission (FCC), or equivalent national regulatory body, licensing. However current solutions use frequencies that the US government has decided to leave unregulated. This underused band offers a large frequency range which, because of the lack of governmental red tape, can be installed and used immediately. These unregulated frequencies are also resistant to interference. That is partially because of the relative lack of traffic in the band, but also because these point-to-point microwave signals are transmitted using a highly directional antenna, with an extremely narrow beam, it is unlikely that two signals would come close to interfering with each other.
The dollars and sense of broadband wireless
As we have seen, broadband wireless provides high-capacity, high-quality data and voice connections, but then so do other “big pipe” connections. So why choose broadband wireless over leased lines or fiber? The answer for many managers is found on their financial statements. When one compares the cost of equipment and installation of a broadband wireless system with monthly access fees charged by a leased-lines service provider, the wireless advantage is obvious. Compare a wireless WAN to leased lines and you’ll see the break-even point can be in as little as 12 months compared to the equivalent leased lines. Higher capacity networks pay for themselves even faster. And, of course, each additional month provides greater savings over leasing fees. When equal service levels are compared side-by-side, wireless service is clearly the cost-effective choice.
Total Capacity Acquisition Cost Monthly Cost Three Year Cost
(includes three year schedule for depreciation if applicable)
12.35 Mbps 12.35 Mbps 45 Mbps 45 Mbps Installation = $4,000 $32,000
(includes Lynx.GX 8T, 2 antennas cables, installation)
Installation = $5,000 2 DS3 Router Cards = $16,000
(new routers/switches may be required)
$25,000
(includes Tsunami.GX 90 link, 2 antennas,
$94,000 $44,100 $201,000 $34,560 $2,500 $1,225
(depreciation, ServPak support, and extended warranty)
$5,000 (lease) $960 (depreciation, ServPak 8 Leased T1 Lines Wireless Lynx.GX 8T DS-3 Leased Line Tsunami.GX 90
Proxim—20 years of wireless leadership
With over 20 years experience in providing reliable, high-speed wireless connections, Proxim is a leader in Wi-Fi and broadband wireless networking equipment. Proxim is the source more IT professionals turn to for the most advanced wireless networking solutions. Among Proxim’s achievements is the world’s first license-exempt spread spectrum T1/E1 capacity link. It makes wireless competitive with hard-wired systems in terms of speed and capacity, while providing a robust link at lower cost than the alternatives.
Proxim’s products offer all the equipment and associated software necessary for high-speed wireless connections. The principal outdoor networking products are:
Tsunami
A family of wireless Ethernet, Fast Ethernet and Gigabit bridges which are ideal for connecting enterprises and ISPs. Uses include point-to-point and point-to-multipoint connections between LANs in buildings, providing true “last mile” ISP connectivity, and linking facilities to an IP backbone. Customers can choose from a variety of point-to-point connection speeds and capacities from 11 Mbps to 860 Mbps aggregate throughput to match the application. Point-to-multipoint speeds range from 11 to 60 Mbps with 360 Mbps total capacity per hubsite.
Product Line Tsunami 480 Tsunami 100 Tsunami 45 Tsunami.GX 90 Tsunami 10
Tsunami Point-to-Point Wireless Ethernet Bridges
Aggregate Capacity Full Duplex Data Capacity Additional T1/E1 Frequency Band Range (miles/km) > 870 Mbps 206 Mbps 206 Mbps 93 Mbps 93 Mbps 93 Mbps 96 Mbps 24 Mbps 24 Mbps > 430 Mbps 100 Mbps 100 Mbps 45 Mbps 45 Mbps 45 Mbps 48/46.5/45 Mbps 10 Mbps 10 Mbps 4xT1 2xT1 2xT1 T1 E1 T1 0/T1/2xT1 T1/E1 T1/E1 5.3/5.8 GHz 5.8 GHz 5.3/5.8 GHz 5.3 GHz 5.8 GHz 23 GHz, 5.8 GHz 5.8 GHz 2.4 GHz Low or High Power
> 6.4/10.3 > 15.8/25.5 > 5.0/8.1 > 7.0/11.3 > 15.5/25.0 > 4.0/6.5 or > 31.4/50.7 > 15.5/25.0 > 26.9/46.8 > 7.0/11.3
Product Line Position Within
Tsunami Family AggCapacity regate
Additional T1/E1 (Wayside) Maximum Distance Frequency Type
Frequencies Configuration Ethernet
Interface
NetworkManagement
Support
Tsunami Multipoint 5.8 GHz
Point-to-Multipoint 20 or 60 Mbps – 6 miles License-exempt 5.8 GHz Indoor + Outdoor 10/100BaseT SNMP, HTTP
LYNX
A product line of T1/E1 spread-spectrum license-exempt wireless interconnection solutions with speeds up to DS-3, these connections are both robust and secure due to their advanced technology. Lynx products find wide acceptance in providing backhaul connections.
Conclusion
Broadband wireless is a viable alternative to expensive leased lines
Broadband wireless has made significant advances vis-à-vis physical cable connections where connection speed, capacity, physical access and cost are considerations. It offers close to the speed and capacity of fiber optic networks but has significant advantages in being able to span distances of up to 40 miles without laying cable which results in major cost savings as well as almost negligible time of deployment. Capacity of broadband wireless ranges from 10BaseT to Gigabit Ethernet, or from T1 to DS-3 levels. With broadband wireless,
enterprises, healthcare organizations, educational and governmental institutions and ISPs can economically offer their users the bandwidth that those users demand—bandwidth that is rapidly becoming the standard for connection rather than a luxury. Broadband wireless solutions can be implemented quickly, often in days, and do not suffer from the fees and delays that are endemic to Telco-installed solutions. When one considers all of the factors from capacity to price to ease-of-installation, wireless has emerged as the best choice for networking between LANs and other critical connection applications.
Contact Proxim for additional information
Additional technical information as well as use analysis and cost estimates are available from Proxim. Call 800-229-1630 toll-free or visit www.proxim.com on the Web. Proxim can customize a broadband wireless solution to meet your needs.
Appendix: Case Studies
Wireless makes the grade for college system
Allegany College of Maryland operates five instructional sites in three counties and two states. To connect the sites Allegany created its own communications network, custom designed for its needs. The new fully integrated communications network combines voice, video, data and Internet using broadband wireless technology to link the various sites and buildings located in the area’s mountainous terrain.
Previous to the broadband wireless system, Allegany had leased T1 lines. Administrators were unhappy with the performance and cost of that solution. “Every time a circuit went down (which happened once or twice a month) we had to deal with five phone companies,” recalls Jon Moore, IT manager for the college system. “It was a disaster trying to get it all back up and running again.”
Cost was also a concern. “Every few months, the bill would go up,” says Moore. Over a period of just a few years monthly Telco fees had inflated by over 30%.
Allegany’s administrators decided to install broadband wireless connections in place of the leased-line system. The results were improved reliability (not one break in communications has been attributed to the new network), increased signal quality (including video) and increased capacity. Where the leased lines provided a three quarter T1, the new wireless system provides a full T1 connection carrying 1.5 megabits of information. Wireless also makes better business sense for Allegany. The system will be entirely paid for and owned by the college within six years—with lower monthly expenditures during the payback period.
Wireless provides a better connection for ISP
Zoolink Communications Ltd. is an Internet Service Provider in Vancouver, British Columbia, Canada. They needed to create a high capacity connection from a Point of Presence (PoP) to a business customer. The principal
consideration in selecting a connection medium, in addition to capacity, was reliability.
After considering leased lines, Zoolink decided on broadband wireless. A 100BaseT 45 Mbps 5.8 GHz bridge was installed to connect the customer to Zoolink and to the Internet backbone. The result is extremely reliable
performance. There has been no interruption since deployment. It should be pointed out that unlike some wireless communications, broadband wireless operates at frequencies that are not disrupted by weather. Performance is on par with fiber optic.
Broadband wireless is often the better choice for ISPs. It eliminates the need to pay access dollars to the local Telco. It is reliable. The quality and capacity of the connection are excellent. With broadband wireless, ISPs can affordably offer T1/E1 data and voice service to small businesses. And they can provide DS-3 service with wayside T1/E1 for data, video, Internet/IP and PBX traffic to larger businesses. And 10BaseT service can be delivered to cost-conscious subscribers.
The bottom line for ISPs is that broadband wireless allows them to provide better, higher-capacity service to more customers while retaining more revenue. Payback for the average installation is measured in just months.
Johns Hopkins finds cure for slow connectivity
The Johns Hopkins University Applied Physics laboratory supports a variety of governmental agencies by providing innovative applied research, technical development and problem solving. But even so advanced an institution still had connectivity issues to resolve when a new campus facility was constructed less than a mile from the main campus data center. Johns Hopkins decided that the best, least expensive way to link the two facilities was via broadband wireless.
Two 100BaseT 100 Mbps full duplex bridges were installed providing outstanding throughput between the LANs of the two facilities. In addition, the wireless link supported existing Cisco AVVID VoIP telephony.
One further advantage of the broadband wireless bridge to the University is that it provides redundancy to existing fiber infrastructure.
The speed of connection is 100 Mbps, but how fast was the installation? The system was installed and ready to use within three weeks of issuing the purchase order.
Wireless connects Southern California Tribes
Under a grant from the National Science Foundation to the University of California at San Diego, Native American tribes in Southern California now have high-speed wireless connectivity for education and other tribal needs.
Three reservations are now connected along with the University in the High Performance Wireless Research and Education Network (HPWREN), a collaboration between UCSD and the Southern California Tribal Chairman Association. Wireless was chosen because of its cost-effectiveness and ease of installation. Connections span many miles of rugged land where trenched or aerial wire would be very difficult and costly to install. The network uses 45 Mbps point-to-point links with high-speed wireless access to individual users provided by low-cost Wi-Fi radios.
The outcome is that all three reservations now offer educational programming for K-12 students as well as adult education utilizing the high-speed network. This has led to a very successful UCSD distance-tutoring program for local youth as well as adult introductory classes to computers, the Internet, HTML, and graphics design. The Pala Learning Center has been compared to the best community technology centers in urban America. Future plans for the network include a new Headstart center that will be fully wired to utilize the HPWREN connectivity for pre-schoolers as well as an expanded adult curriculum.
Installation of the network was accomplished in months instead of years and cost a few hundred thousand dollars instead of a few million dollars compared to the time and cost of hard-wire connections.
