Wi-Fi Meets VoIP

Posted: 1/2004

Wi-Fi Meets VoIP
Connection Creates Opportunities for Channel Partners
By Ben Guderian

Wi-Fi technology is getting a lot of
attention mostly in the consumer and public network areas. But, Wi-Fi WLAN networks also are being embraced in hospitals,
retail stores, schools, factories and even general offices as ways to improve
communication and lower costs. However, office workers who increasingly are
freed from their desks by wireless laptop computers still need to make and
receive telephone calls. Being tied to a telephone wire negates the benefit of a
wireless data device. Fortunately, the same Wi-Fi technology that allows computers
to communicate over the air can be used for voice communication as well.

Voice over Wi-Fi, or Wi-Fi telephony, bridges traditional
telecom, datacom and mobile technologies. A Wi-Fi telephone is functionally equivalent to a wired
telephone, just like a home cordless phone. It also is a wireless LAN client
device, using the same network technology as wireless laptops and PDAs. Finally,
it is a mobile communication device unencumbered by wires, just like a cellular
telephone or walkie talkie. With its split personality, Wi-Fi telephony offers new
revenue opportunities for channel partners in enterprise telecom, datacom and
mobile marketplaces.

INTERCONNECT OPPORTUNITIES

Resellers of telephone equipment and systems can
use voice-over-WLAN technology to extend their traditional wired solution
offerings into the wireless space. In the past, telephone systems providers have
had minimal success selling wireless applications to most of their customer base
due to the high cost of the available solutions.

In North America, adoption of wireless has been limited to
markets with a strong need for mobile communication in the workplace,
predominantly in health care and industrial applications. In contrast, the
adoption rate of enterprise wireless in Europe and some areas of Asia has been
much higher thanks to a standards-based wireless voice technology. The Digital
Enhanced Cordless Telephone (DECT) standard is used for both business and
residential applications, allowing broad industry support and lower equipment
costs. But DECT is not available in North America due to different frequency
band allocations, so the North American market has been constrained by more
expensive, proprietary wireless technologies until now. Wi-Fi technology is
based on the global 802.11 standard, making it even more ubiquitous than DECT
with much broader industry support. Wi-Fi component and equipment costs already have seen drastic
reductions due to widespread adoption in both enterprise and residential
markets. Voice over Wi-Fi solutions can take advantage of the lowering
costs of Wi-Fi networks, making them attractive in both vertical and general
markets. The cost of a Wi-Fi telephone still is much higher than that
of a residential cordless phone, so voice over Wi-Fi is not ready for the home
market. But in the enterprise market, where wired business telephone
sets cost hundreds of dollars, Wi-Fi telephony is becoming a viable solution.

Wi-Fi networks use IP technology, making them an ideal fit for
VoIP telephony applications. The synergy between VoIP and Wi-Fi technologies make wireless
voice applications less expensive and easier to install and maintain. Enterprise
telephone systems using VoIP are available from all the leading PBX providers as
well as new entrants in the market that are specializing in IP technology. Most
IP telephony systems use unique, proprietary protocols to communicate between
the telephony server and the IP telephones, so Wi-Fi wireless telephones need to
provide multiprotocol support. Standard VoIP protocols such as H.323, Media
Gateway Control Protocol (MGCP) and Session Initiation Protocol (SIP) also are
supported by some systems, and probably will have wider support as these
standards mature.

For traditional circuit-switched telephone systems, wireless
voice gateways are available to packetize the voice signal for delivery over the
Wi-Fi network. Although a gateway solution adds cost to the overall solution, in many cases it is less expensive than
upgrading or replacing a circuit-switched PBX to support VoIP technology.

DATA RESELLER OPPORTUNITIES

The attributes that are making Wi-Fi technology a
success standards and lower costs also are making it a commodity. Many
startups and veteran companies are developing products to add value by improving
the security, maintenance and administration of Wi-Fi networks, further lowering
the total cost of ownership. Although we are still in the early stages of the
Wi-Fi market, it is likely that it will soon become as plug and play as
todays wired Ethernet technology. Wi-Fi with telephony, however, enables data
network VARs and system integrators to offer enhanced and differentiated
networking solutions. In the proposal stage, adding a wireless voice component
can expand the scope of a project and possibly free up more budget for a
wireless program. For existing customers, adding Wi-Fi telephones to an existing
wireless network is an opportunity for network expansion and incremental
revenue.

Adding voice devices to an enterprise Wi-Fi network is
relatively simple, but there are a few considerations to take into account.
First, the wireless LAN coverage area may need to be expanded to cover areas
where mobile voice devices will be used. Wireless data usage usually is limited to offices, conference
rooms and lobby areas, while wireless voice devices also will be used in halls,
stairways, smoking areas and even lavatories. Second, the additional network
traffic generated by wireless telephones may diminish throughput for data
devices. Wireless voice traffic can be predicted using traditional telephone
usage algorithms, and various mechanisms are available to set a limit on voice
calls to guarantee a minimum amount of bandwidth for data applications. Lastly, wireless LAN security methods that work for data
applications might not work for voice applications. Voice, a real-time
application, cannot tolerate the delays caused by some VPN implementations. Also, some authentication protocols cause a significant
interruption in the data stream when a device is roaming between access points. Fortunately there are various middleware solutions to address
these issues, and the industry is developing standards for prioritizing voice
packets and providing network security.

WIRELESS AGENT OPPORTUNITIES

Wireless resellers traditionally offer licensed
radio and cellular solutions to enterprise customers. Private radio systems primarily are targeted at wide area
applications such as dispatch, fleet management and public safety. But many
enterprise customers use private radio systems or cellular phones wholly within
their facilities because of the low startup costs and the large coverage area.
But even with a free cellular telephone, typical monthly airtime charges average
more than $50, adding up to at least $600 annually. In contrast, wireless
telephones utilizing an enterprise Wi-Fi network sell for $400 to $700 with no
airtime or usage charges.

An even greater advantage of Wi-Fi telephones over cellular
phones in an enterprise environment is the functionality they provide. Wi-Fi telephones integrate with the facilitys internal
telephone system and work like wired desktop phones. This allows the wireless
telephone user to transfer calls, set up three-way conference calls, answer
alternate extensions and utilize the companys voice mail system. For
applications that need the group calling capability of mobile radio systems,
some Wi-Fi telephones also provide push-to-talk functionality while still
delivering all the telephone system features that are not available with a
traditional push-to-talk radio.

NEW ECONOMICS AID THE SALE

In some industries such as health care, retail and
manufacturing, the need for mobile communication is sufficient to justify
installing a Wi-Fi network just for voice applications. For other enterprise
applications the opportunities for Wi-Fi telephony are driven by both mobile
voice and data applications. But there is another factor that can lead to wider
deployment of Wi-Fi in the enterprise environment the cost of installing and
managing wiring for voice and data. As Wi-Fi infrastructure equipment continues
to decline in price and total cost of ownership, new opportunities will arise to
use wireless as a cost-effective alternative to phone and data cables.

With wiring costs starting around $150 for each connection (or
about $300 per employee that has both a phone and a computer), it doesnt take
much for wireless to be a lower cost alternative. A single Wi-Fi access point
can serve the voice and data needs for a dozen or so users, depending on their
data bandwidth needs. With the average installed cost of an access point now
well under $1,000, it is easy to justify a wireless network on wiring cost
savings alone.

These economics open up new opportunities for all types of
resellers. Those that offer wiring and installation services for telephone
and/or data networks need to be able to propose wireless alternatives to remain
competitive. Mobile radio and cellular providers also will want to offer Wi-Fi
solutions as lower cost alternatives that in many cases offer higher
functionality.

Wi-Fi technology is bringing new opportunities to provide
enterprise customers with standardsbased networks that can support both voice
and data applications on a single infrastructure. The rapid pace of technology
is making Wi-Fi a costeffective technology for all kinds of applications and
bringing the simple experience of the home cordless phone into the enterprise
environment.