April Issue of the Taos Newsletter: Wireless Networking

Wireless Networks – An Emerging Technology for Enterprise Productivity

by Rita Khayat-Toubia, CIO of Proxim, as summarized by Jerry Brocklehurst

As a technology that is beginning to show up in primary networks in more and more enterprise environments, Wi-Fi* can have significant advantages for improving employee productivity and communications. At the same time, the implementation of Wi-Fi can be complex and confusing. But does it need to be?

The answer is a simple “no”. In a recent Experts in the Industry presentation hosted at Taos, Rita Khayat-Toubia, CIO of Proxim, helped cut through the questions and issues surrounding the topic of Wireless Technology to provide a simple and clear understanding.

Wireless – What is it?

For starters, “Wireless” can mean many things to many people. For example:

But rather than a collection of many things, perhaps a more helpful way to think of wireless is in categories.

In other words, there are wireless devices such as cordless phones, cell phones, remote controls, etc. Then, there are wireless applications such as wireless internet, e-mail, inventory management, and calendaring. All of these, of course, make use of wireless technologies that include IEEE 802.11, GPRS*, Bluetooth*, WiMax, RFMicrowave, and others.

Finally, when combining devices, applications, and technologies with the network, we have the beginnings of an organized picture of Wi-Fi. However, to have a complete picture of Wi-Fi, it’s important to understand more about the different types of underlying wireless networks.

A Wireless Network Primer

Seamless connectivity (see Figure) can be achieved through a combination of 4 types of wireless networks, each with ever-expanding areas of coverage:

• WPAN – Wireless Personal Area Network
• WLAN or Wi-Fi– Wireless Local Area Network
• WMAN – Wireless Metropolitan Area Network
• WWAN – Wireless Wide Area Network

WPAN typically operates within about 30 feet and utilizes bluetooth, IEEE 802.11 (U.S.), or ETSI HiperPAN* (Europe) standards. A WPAN generally is focused on interconnecting devices centered around an individual person's workspace, such as laptop, PDA, and cellphone. A key concept is that WPAN devices seamlessly connect with each other as if connected by a short cable. Again, the focus is on connecting an individual’s devices rather than multiple people’s devices.

WLAN operates within 300 yards and uses 802.11 or ETSI HiperLAN* standards. WLAN is the Wi-Fi for enterprises and is the primary focus of this article. While it has some limitations, there are many advantages that we will return to later.

WMAN is based on IEEE 802.16, or ETSI HiperMAN* and HiperACCESS standards and is one of the most interesting areas for the future. There are currently a number of companies and groups working to develop WMAN, including WiMAX (Worldwide Interoperability for Microwave Access) – a non-profit group that is backing the development of wireless MAN products based on 802.16 and working on standards certification and interoperability testing. WMAN and WiMAX are really the next step on the road to a “wireless world” with certifications to begin in 2005.

The vision for WMAN is to extend the range of Wi-Fi and to be either an alternative or a complement to WWAN 3G* technology, supporting both fixed and mobile applications as well as voice and multimedia data. Today, wireless MANs exist, but are based on proprietary technology solutions. The focus of the new work around standards is in three areas:

• IEEE 802.16a (<11 GHZ; Non-line of sight; 31 miles range; 70 Mbps; fixed),
• IEEE 802.16 (10-66 GHZ; requires line of sight; fixed), and
• IEEE 802.16e (<6GHZ, Non-line of sight, up to 15 Mbps at 5MHZ; pedestrian mobility; regional roaming)

Applications are expected to include “last mile” access, campus connectivity, and redundant links. Ultimately, WMAN may also become competition for cable TV and landline phone companies – streaming video over broadband connections to replace existing cable and DSL connections, and replacing cordless home phones by Wi-Fi cell phones.

Lastly, WWAN continues to evolve from 1G* (9.6Kbps) through 2G* (9.6Kbps GSM and 19.2Kbps CDMA and TDMA) and 2.5G* (100 – 150Kbps Richochet and GPRS) to 3G* (144Kbps – 2Mbps CDMA2000 and WCDMA). Standards include IEEE 802.20 (proposed) in the U.S. and 3GPP and EDGE* in Europe. Applications include complete mobile computing, but the key challenges of coverage, reliability, speed, costs, and standards must first be addressed.

WLAN – An Advantage for Today’s Enterprises

With a coverage area of 300 yards, WLAN is well-suited for use within enterprises - the range is wide enough to provide reliable service to employees, yet narrow enough to reasonably limit access to outsiders.

The following IEEE standards are in use today for WLAN:

• 802.11b (2.4 GHZ - 11 Mbps)
• 802.11a (5 GHZ – 54 Mbps)
• 802.11g (2.4 GHZ – 54 Mbps)

For the most part, the same applications that use wired LAN can also leverage WLAN. These are e-mail, internet access, general network and database access, and calendaring to name a few.

The biggest advantage, then, is really mobility. More mobility means more productivity – access to information as needed, when needed. For example, with a WLAN in place, employees can easily move about their company campus with their laptop, taking it from their office to a meeting in a conference room. When information is needed for a critical decision, it can be obtained quickly and easily - no more waiting until later. And these same advantages extend to visiting suppliers, partners, and customers as well. Corporate hotspots and access points can be made available to guests for simple, easy access to the internet while maintaining security of the company network. With a higher level of mobility, productivity improves for everyone.

Outside the walls of the enterprise, employees also gain the convenience of being able to connect seamlessly to their wireless home networks or to other company networks. Again, productivity improves as they can, in effect, take “their office” with them wherever they go.

Beyond employee convenience and productivity, there are other major drivers for the enterprise. First, there is the overall lower cost of the infrastructure itself. Wired systems are expensive to install and maintain. Next is the reduced cost of moving employee offices – there is no wiring to expand or re-route. And deployment of new systems is fast and easy when new employees are hired or computer systems are upgraded or changed out. An additional benefit of WLAN is the possibility of reduced communications costs through implementation of VoIP.*.

WLAN is currently limited, but on the rise

To date, the limited extent of Wi-Fi deployment within an enterprise has been directly related to the adoption of portable devices and to mitigating both perceived and real security gaps. Most current Wi-Fi installations cover only specific areas of the enterprise such as conference rooms, office areas in a corporate facility, particular manufacturing floor areas, certain wings in hospitals, and specific buildings on a university campus. A recent survey (NOP, November 2003) of mid and large size U.S. companies with wireless LANs provides some data points:

• 27% have WLAN deployed company-wide
• 22% of employees on average have access to the Wi-Fi network
• 17% of employees in manufacturing have access to the Wi-Fi network
• Many departments have low access
• Over half of end-users that do have Wi-Fi access use it daily

While implementation of WLAN has been slow to date, other data clearly shows that its use is on the rise:

• Over half a billion of mobile devices will be sold in 2004
• 50% of new laptops in 2004 will have integrated Wi-Fi chips (Dell Oro)
• 30% of PDAs will have integrated Wi-Fi chips in 2004 (Gartner Group)
• Hot spots are growing by 40/60,000 per year worldwide
• 75 million hot spot users are expected by 2008
• Hot spots include travel locations, coffee shops, and communities including Universities
• Wireless Service Providers are seeing increased revenues from bundled services

Yes, WLANs can be secured

One of the key drivers behind the recent growth of WLANs is the acceptance that they can be secured through proper implementation of today’s powerful authentication and encryption technologies. Basically, this means the following:

• Have an infrastructure that supports Wi-Fi Protected Access (WPA) via 802.1X standards
• Implement authentication with rotating keys and TKIP*, and
• Make sure your vendor will support software upgrades to AES and 802.11i standards in the future

In addition to building a secure network through the above measures, it is also important to keep your network secure through proactive monitoring measures such as Advanced Rogue Access Point detection. Technology is available to automatically search both 2.4GHz and 5GHz bands to detect and identify rogue access points and shut them down, thereby preventing security breaches.

Trends and Conlusions

As we look at both the drivers of wireless technology and then at the technology itself, some exciting trends are evident.

First, workers are becoming more mobile – traveling more, telecommuting more, attending more offsite meetings, and generally spending less time in fixed offices. Today, usage is mainly stationary, but tomorrow it will be highly mobile.

Second, data and voice are becoming integrated everywhere. Cellular carriers already support IP packets, allowing data to pass over existing voice networks. At the same time, we see voice passing over data networks through VoIP. A convergence is on its way.

As usage continues on the path toward higher and higher mobility, it will continue to drive a technological evolution of the Device, the Network, and the Application. We will see fully integrated voice and data networks, a complete convergence of Wi-Fi and cellular networks, and enterprise-wide adoption and coverage that will ultimately extend, through WPAN, WLAN, WMAN, and WWAN worldwide with seamless connectivity.

Rita Khayat-Toubia is CIO of Proxim. For more information on wireless technology, please visit www.proxim.com.

*Glossary

• 1G, 2G, 2.5G, & 3G : Specifications for the various generations of mobile communications technology. Analog cellular is the first generation and digital PCS is the second. 3G promises increased bandwidth and will work over wireless air interfaces such as GSM, TDMA, and CDMA.
  
• Authentication : Security mechanisms such as user ID, passwords, and unique device keys that are used to identify a wireless client to an access point and vice-versa.
  
• Bluetooth : Bluetooth is a telecommunications industry specification that describes how mobile phones, computers, and personal digital assistants (PDAs) can be easily interconnected using a short-range wireless connection through a low-cost transceiver chip in each device. The tranceiver transmits and receives in a previously unused frequency band of 2.45 GHz that is available globally (with some variation of bandwidth in different countries).
  
• CDMA : Short for Code-Division Multiple Access, a digital cellular technology that uses spread-spectrum techniques. CDMA does not assign a specific frequency to each user. Instead, every channel uses the full available spectrum with individual conversations encoded through a pseudo-random digital sequence.
  
• EDGE : Acronym for Enhanced Data GSM Environment. EDGE is a faster version of GSM wireless service.
  
• Encryption : The translation of data into a secret code, typically through use of a secret software “key”. Encrypted data can only be decrypted by someone through use of the secret key. Encryption protects data from being intercepted and understood by an unauthorized person.
  
• GPRS : Short for General Packet Radio Service. GPRS is a standard for nonvoice wireless communications that allows information to be sent and received across a mobile telephone network at speeds up to 115 kilobits per second, compared with the 9.6Kbps of GSM (Global System for Mobile Communications) systems. It is particularly suited for sending and receiving small bursts of data, such as e-mail and Web browsing, as well as large volumes of data.
  
• GSM : Acronym for Global System for Mobile Communications. GSM has become the de facto standard in Europe and Asia for digital cellular systems.
  
• HiperLAN, HiperPAN, & HiperMAN : Short for high performance radio local (or personal, or metropolitan) area network. HiperLAN, HiperPAN, & HiperMAN are a set of communication standards developed by the European Telecommunications Standards Institute (ETSI) and used chiefly in European countries - similar to the IEEE standards in the U.S.
  
• TDMA : Short for Time Division Multiple Access, a technology for delivering digital wireless service using time-division multiplexing (TDM). TDMA works by dividing a radio frequency into time slots and then allocating slots to multiple calls. In this way, a single frequency can support multiple, simultaneous data channels.
  
• TKIP : Short for temporal key integrity protocol. TKIP is a security mechanism that 1) scrambles software security keys using a hashing algorithm, and 2) adds an integrity-checking feature to ensure the keys haven’t been tampered with.

• VoIP : Short for Voice over Internet Protocol. VoIP technology sends voice through IP packets across the internet, allowing two-way voice communications similar to phone lines.
  
• Wi-Fi : Short for wireless fidelity - a generic term when referring to wireless devices, applications, technologies, and networks.