Application software is plentiful for IrDA-enabled devices, and many cellular phone, computer peripheral, and laptop companies have a built-in IrDA solution. My impression, though, is that manufacturers are just biding their time until Bluetooth takes hold. At that point, expect a mass migration, especially as the range of operation increases from 10 m (Class 1 and 2) to 100 m (Class 3)—the required distance for effective operation within a corporate office building.
On the home front, Bluetooth was originally thought to be competing with wireless standards such as the 10-Mbit/s HomeRF with its direct-sequence, spread-spectrum modulation scheme, and SWAP, the shared wireless access protocol (Fig. 1). But Bluetooth's 1-Mbit/s data rate makes this unlikely. Instead, the two will complement each other. HomeRF devices have a solid backing and a critical mass of enabled product lines about to hit the market. So if they don't maximize upon the head start they have over Bluetooth, they might lose their window of opportunity in the coming year. Bluetooth isn't standing still, with work already in progress for a 10-Mbit/s version by 2002.
Together, these two wireless interfaces have the upper hand over wire-based standards, which depend on a home being either wired with phone lines in every room (HomePNA) or other complete rewiring. In the past, those standards remained feasible due to the extremely wide price disparity that existed, say, between wired Ethernet setups and wireless implementations. But that contrast has weakened enough to make the argument against wireless utterly insignificant.
The next stage of connectivity deals with how the information will be shoveled from the home or office to the outside world, onto the backbone, and vice versa. Here's where much of the activity, with respect to mergers and affiliations, has taken place over the last few months. Take, for example, Sprint and MCIWorldcom's $115 billion announcement back in September.
Until the start of this past November, there were two realistic broadband options: cable and DSL. A recent FCC ruling, which allows satellite-transmission stations to carry network channels, might help that medium in rural Indiana. There, they don't care if the local news happens to come from Chicago; they're just happy to get coverage at all.
While satellite transmissions boast a great picture, they do suffer from a slow download rate for Internet access (in the range of 300 kbits/s) and nonexistent upload (a phone line must be used). These factors make it highly unlikely that satellite will be the medium of choice in more populated areas. Cable and one or other various DSL versions will dominate. Integrated-services digital networks (ISDNs) will go away, while T1/E1 lines will remain popular for the installed base, comprising mainly offices.
While a head-to-head technology comparison of DSL versus cable might explain why one is better than the other, their relative potential for success in this new era has more to do with business and coverage issues than anything else. Yes, DSL is easy to install. The splitterless G.lite version even obviates the need for a service technician to come to your door. On the other hand, cable is already installed in a vast number of households.
The Next Decade's Workhorses
That's actually part of cable's problem, however. The cable companies didn't tell us that our service degrades as our neighbors come online because they also see the advantage of an already-installed medium. And both technologies are plagued by coverage and quality-of-service issues. They may soon be surpassed by a rising level of support for alternative media, such as fixed wireless and fiber-optic lines—the workhorses of the next decade.
Thankfully, there's been substantial research into a technology called vectored orthogonal frequency-division-multiplexing (VOFDM). A fixed, wireless local-loop connection might soon be realized in a multichannel, multipoint distribution service (MMDS) scheme. This holds the promise of local, high-speed, indoor wireless connections in non-line-of-sight environments.
VOFDM is key because it allows multiple channels to lie side by side, with minimum bandwidth requirements and up to two usable antennas. These antennas can detect and, hence, decode the transmitted signal accurately, despite multipath interferers. The wireless connection may enable a typical data rate of 20 Mbits/s in both directions in a 6-MHz channel. Doubling the channel to 12 MHz could give a throughput of up to 40 Mbits/s.
Fiber-optic connections to the home remain the ideal, but they're still a long way off. Going wireless, as with VOFDM, has the advantage of wide coverage (up to 10 miles) and a minimum of hardware investment in terms of laying down lines or purchasing dark fiber. But like most technologies, its success depends heavily on how quickly it can be disseminated.
Beyond the realm of the house or office, things get a little trickier. Mobile reception and transmission have been available to the masses for a number of years. For the most part, they're even quite adequate. But that's all changed with the desire for broadband access. The 14 kbits/s available on the typical wireless phone is laughable in the face of a burgeoning need for the 150-kbit/s, 384-kbit/s, or even 2-Mbit/s data rates being planned for third-generation (3G) wireless phones.
It's a straightforward matter to design a wireless, Internet-enabled telephone capable of 114-kbit/s reception. In practice, though, you'll need a lot of luck finding support for that rate. The norm is 14 kbits/s. This problem has to do with coverage and infrastructure. Billions of dollars are invested in the current network of cellular base stations. To upgrade would incur losses on the carrier's part.
They can, however, configure the base stations for upgraded service at 150 to 384 kbits/s. That's most likely to happen over the next year or two, at the expense of user density.
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