The Last Mile: Streaming’s Bottleneck

Broad but not Ultrabroad
ADSL, or Asynchronous Digital Subscriber Line, is not a DSL replacement, as it has the same inherent range limitations that have spurred innovators to find alternatives. The farther the user is from a central hub, the slower the connection they are capable of obtaining. ADSL service has a maximum distance of about three miles. What it does offer are connections up to 8Mbps download, although the typical home user can only realize 1.5Mbps service, which is widely, although not universally, available in urban and suburban neighborhoods. ADSL utilizes the same copper phone lines as DSL and, like its slower predecessor, allows for simultaneous phone/Internet usage.

Accessing the Internet via satellite doesn’t offer nearly as much in terms of bandwidth, with connection speeds under 1Mbps. But if you’re somewhere outside the scope of other broadband solutions, satellite might be your best—and only—option.

BPL, or "broadband over power lines," enables 3Mbps over a house’s existing electrical wiring. As a part of his call for universal, affordable access to broadband by 2007, President Bush has expressed his support of BPL as a way to bring broadband into every home. In March, Cinergy Broadband, a subsidiary of Cinergy Corp. and Current Communications Group announced that it was beginning to offer BPL in the greater Cincinnati, Ohio area. BPL raises the interesting possibility of the Internet as a public utility.

The DSL-replacement technology that seems to have the most momentum among its developers is the still nascent WiMAX standard, which allows for the wireless transfer of data via radio frequencies. WiMAX was created in an attempt to unite 802.16, the direct descendant of 802.11 (aka Wi-Fi), with ETSI HiperMAN, the European equivalent of the 802.16 standard, under one umbrella brand. WiMAX hitches users onto the Internet via towers; one especially attractive future option may involve simply retrofitting cell phone towers to transmit and receive a WiMAX signal. A sign of WiMAX’s momentum can be found in Intel’s involvement with the development process, including their plan to incorporate WiMAX technology into PCs starting in 2006 or 2007.

With a range of five miles, WiMAX has been openly referred to as a DSL replacement and primarily targets "underserved markets in developed countries and emerging markets in developing countries," according to Michael Cai, a Parks Associates senior analyst who recently compiled a comprehensive report on the state of wireless broadband. Cai sees developed countries with government mandates for 100% broadband coverage, like the U.K. and Germany, as the first markets that will fully take advantage of what WiMAX has to offer.

While WiMAX provides a solution for bridging the last mile, especially in rural areas, it’s initially only going to be able to handle 75Mbps per tower, which would be shared among any number of end users. "That number is quoted quite a lot," says Cai, "but it’s only based on certain bandwidth and certain channel size and certain modulation. It’ll probably be closer to 20Mbps and could be even less." Considering its pedigree, WiMAX will most likely continue to grow into a viable broadband alternative for rural communities, but it won’t be a serious contender to bring high quality, full-screen streaming video until it can handle a lot more bandwidth per tower.Free Space Optics
Free space optics (FSO) technology works by transmitting wireless, point-to-point laser signals that can handle up to 10Gbps. Because of its cost, FSO is typically used by corporations for one of two tasks: connecting buildings with high-speed Internet access points or extending a company’s high-speed network between two buildings without the need for laying cable. "At one point, FSO was looked at as lasers going through every window," says Jeff Bean, director of marketing at LightPointe, a manufacturer of FSO technology. "But it’s not feasible from a cost standpoint." LightPointe’s packages start at $5,000 for a 10Mbps system, which provides the two lasers and installation but not fees to your ISP for the Internet access itself. "We’re not in the business of setting up Internet services," says Bean.

Cost isn’t the only thing keeping FSO from bridging the last mile into people’s homes. Another impediment is its somewhat limited three-mile range. Also, FSO is a line-of-sight technology, meaning that the two lasers need an unobstructed view of each other in order to transfer data. LightPointe’s top-shelf solution attempts to create enough redundancy to circumvent this limitation by simultaneously transmitting four lasers but only requiring that one laser beam be unobstructed for streaming without packet loss. Even still, FSO struggles with some weather conditions, especially fog. At the same time, LightPointe has seen its products succeed in slicing through everything from sandstorms in Kuwait to the recent Hurricane Charley in Florida.

For the short term, FSO will stay relegated to enterprise applications. "In the long term, if the need was there, you could conceivably set up point-to-point configurations in neighborhoods," says Bean. And an increase in demand could ultimately result in greatly reduced manufacturing costs for FSO technology. The most likely residential use of FSO will be to connect multi-tenant buildings, especially high-rises, to the Internet without the need to rip up streets and lay cable. "Eighty-five percent of the cost of getting fiber in the ground is labor," says Bean. "Going through the air is a lot easier than going through the ground." Bean also doesn’t see FSO as a competing technology to fiber optic cable or WiMAX, but rather a complementary one, especially in urban settings.