Swimming Upstream with Uploads
From P2P to VoIP, demand for upload capacity is surgingbut broadband providers have skimped on bandwidth. Will they finally get the message?
To paraphrase George Costanza, the message boards were angry today, my friend. True, theyre almost always angry when the topic turns to consumer broadband. But lately, the usual complaints about bad tech support and service outages are being edged out by rants of a different sort: people want faster upload speed, and they want it now.
Cable companies have been aggressively upgrading their cable modem services to provide 2- and 3-megabit-per-second downloads, and some DSL providers have doubled their standard rates to 1.5 megabits per second, but upstream increases have been incremental. Meanwhile, demand for upload bandwidth is growing as more and more people telecommute, file-share, play online games, run personal Web servers, and send media-rich e-mail attachments. The recent surge of interest in voice-over IP (VoIP) telephony will only add to the load. More and more people who work from home are running up against the upload limits, says Lisa Pierce, an analyst at Forrester Research.
Although no one is refusing the 3-megabit-per-second downloads, the advantage isn’t as dramatic as might be expected. Due to piracy concerns, theres just not that much high-bandwidth content available on the Web, and high-quality video may be a long-time coming from a cable industry that wants to protect its core video business. Whats more, the maximum rates are often reduced by peak-hour congestion, and Internet service providers have become more and more vigilant in enforcing bandwidth-consumption caps. In other words, youre likely to run into the 3-megabit-per-second cap about as often as hitting 120 miles per hour on the freeway.
Users bump up against upload limits far more frequently. Some providers, such as Verizon DSL and Time Warner Cable, have recently upgraded their customers to 384-kilobit-per-second uplinks. But most broadband users are limited to 256 kilobits per second, and millions still chug along at 90 to 128 kilobits per second.
Then start piling on the applications: Voice over IP, for example, requires 40 to 90 kilobits per second per call. For a VoIP conversation in which both parties are simultaneously accessing the Internet over a shared, home-networked connection, even a typical 200 kilobits per second back channel may not suffice. If you cant perform data access at the same time [as using VoIP] then theres no real advantage to using it, says Pierce.
VoIP calls won’t be able to fully exploit greater bandwidth, however, unless the codecs are redesigned to do so. If voice quality is seen as an obstacle to customer adoption of VoIP, cable providers deploying VoIP may need to boost their uplink speeds accordingly. The technology is ready when they are: last month, ShoreTel introduced the first IP phone to include a 16-bit codec that can exploit up to 256 kilobits per second per channel for better voice quality.
The uploading problem is only going to grow worse, says Matt Davis, an analyst with the Yankee Group. As we move into more interactivity with online gaming and videoconferencing, upstream bandwidth is going to be more important, he says.
Despite the growing awareness of upload limits, cable marketing efforts in particular continue to focus on download speedsand for good reason. The cable companies coaxial pipelines can handle far more traffic than the phone companies copper wires, and they have also invested more in infrastructure upgrades over the last decade. Most cable providers could therefore easily deliver 6-megabit-per-second downloads right now, if they were willing to reduce the number of video-on-demand TV channels. In fact, many could even deliver up to 30 megabits per second per user, if customers were willing to pay for it.
Cable uploads, on the other hand, are severely constrained by current technology. It is unlikely that providers can cost-effectively deliver more than 384-kilobit-per-second uplinks to most subscribers. Fortunately, the latest cable modem standard boosts upstream bandwidth from todays 4.6 megabit per second (per neighborhood loop) up to 30 megabits per second. That means cable providers should be able to deliver upload rates of between 512 kilobits and 1.5 megabits per second per household.
The new cable standard does not require a major infrastructure overhaul, so deployment should begin in early 2005 and the technology should be in wide use by 2007. Because the new version also cleans up a lot of the noise on cable networks, thus improving VoIP quality, cable companies will have a powerful incentive to move quickly. Comcast, for example, recently announced plans to deliver VoIP to 95 percent of its installed base of 21 million TV subscribers by the end of 2005.
If phone companies want to remain viable broadband competitors with their DSL services, they’ll need to keep pace on upload speed. One sign that this may be happening is Verizon DSLs upgrade to a standard package offering 1.5-megabit-per-second downloads and 384-kilobit-per-second uploads, which represents a tripling of upload speed. This summer, meanwhile, Verizon will introduce 3-megabit-per-second downloads and 768-kilobit-per-second uploads; this souped-up connection should be available to the majority of existing customers, according to a Verizon spokesperson. Verizons announcement coincided with the news that it would enter the VoIP market this summer.
Long term, the phone companies must decide between an upgraded version of consumer DSL, which promises modest improvements, and a more far-reaching plan to offer a very high speed DSL that is capable of delivering video on demand. The first DSL version, which could become available as early as next year, offers download rates of up to 24 megabits per second (though in real-world deployments subscribes will probably get between 6 and 15 megabits per second, depending on their distance from the central office). The very-high-speed DSL service, which requires more infrastructure investment because it brings fiber drops closer to homes, delivers up to 50 megabits per second (realistically more like 20 to 30.) On June 22, SBC Communications announced it would invest between $4 billion and $6 billion on fiber upgrades for such a service over the next five years, with one-year trials starting this summer.
Beyond that, both phone and cable companies are planning for a long-term roll-out of fiber-to-the-premises, which would offer bandwidths in the hundreds of megabits per second. Due primarily to labor costs, however, widespread fiber deployment is probably at least a decade away.
So whats the role of upstream bandwidth in all these standards? The next DSL version offers an option for doubling upstream bandwidth, which could place real-world upstream performance at 1 to 1.5 megabits per second; the very-high-speed version would offer much more. Whether the telephone companies (or the cable companies) will actually deploy such bandwidth depends on public demand. As upload-intensive applications grow in popularity, the frustration heard from todays power users is likely to spread. Despite the TV-centric strategies of some broadband executives, after all, the Internet is not just a broadcast medium; its a communications medium.
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