WiMax Operator's Manual

64 CHAPTER 4 ■ SETTING UP PHYSICAL INFRASTRUCTURE
stressed because such attributes were not necessary to succeed in a public utility business,
such as telephony throughout most of its history.
Enterprise grade, as telecommunications professionals see the issue, is a relaxed standard
applying to equipment serving large private networks within corporations and government
agencies. Such equipment is built to a price and sacrifices some reliability to meet a given price
point. Because it is sold not to a few quasi-monopolies but to a myriad of different types of
organizations, it is subject to considerable variation in design and has attracted numerous
manufacturers both large and small.
Enterprise-grade equipment has been characterized by falling prices, a rapid succession
of generations and standards amendments, ever-expanding feature sets and capabilities, and
the use of open standards, interfaces, operating systems, and programming languages. Such
equipment is increasingly self-configuring and self-provisioning.
To date, the majority of broadband wireless metropolitan public networks set up have
used enterprise-grade rather than carrier-grade equipment; that is, they have tended to rely on
wireless local area network (WLAN) equipment. Prior to the confirmation of the 802.16 standards,
relatively little equipment that could remotely qualify for the carrier-grade designation
existed, and what little existed was costly in comparison to enterprise-grade equipment, most
of which was based on the older 802.11 standard for wireless Ethernet.
I have already touched upon the limitations of the 802.11 standard in respect to public
services in the discussion of wireless broadband standards in Chapter 1. Inherent in the
standard itself are capacity, range, and quality of service limitations that discourage using
such equipment in public service networks. That such equipment is relatively less robust,
redundant, and reliable than equipment designed for the carrier market also gives one pause
regarding pervasive public access deployments. Finally, the fact that almost all public networks
of any size attempting to operate with private LAN equipment have failed suggests that
the strategy of employing it is fundamentally wrong. Perhaps the latest generation of modified
802.11 equipment might fare somewhat better in the marketplace, but this has yet to be
demonstrated.
This should, it seems, put the matter to rest. But, as it happens, the issue is not so simple.
Clearly the intent of this book is to promote the new 802.16 standards and to warn against
attempts to substitute wireless LAN equipment in an application for which it was never
designed. At the same time, I should state that WLAN equipment can have a place in a network
that is 802.16 based.
Already, 802.11 equipment is finding a prominent place in a certain rather specialized type
of public network familiarly known as a hotspot. Hotspots may be considered to be the Internet
equivalent of a pay phone—a short-range access point situated in a public space that would
enable an individual with an 802.11-capable phone or computing device to access the Internet
after an online credit transaction. Some tens of thousands of these hotspots are already scattered
across the globe, and their number is increasing daily. Within the overall category of
broadband public networks, they represent the greatest success story thus far.
The installation of hotspots represents a legitimate strategy for the broadband wireless
metro operator, though it should be considered as merely one service offering. Network operators
may also choose to provide backhaul services to other hotspot operators, and in this
market they may be able to compete effectively with the digital subscriber line (DSL) and T1
services favored by most hotspot operators today.