BROADBAND COMMUNITIES is the leading source of information on digital and broadband technologies for buildings and communities. Our editorial aims to accelerate the deployment of Fiber-To-The-Home and Fiber-To-The-Premises.
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56 | BROADBAND COMMUNITIES | www.broadbandcommunities.com | MAY/JUNE 2014 SUMMIT COVERAGE To be fnancially sustainable, a fber network must aggregate demand from multiple sources. Tat's why network builders today are designing unifed infrastructures that can serve all types of customers instead of designing the siloed networks of the past. Tis trend is taking place at local, regional and state levels, said Joanne Hovis of CTC Technology & Energy at the "Aggregating Network Demand" workshop. A unifed infrastructure can be operated either as a single network or as multiple networks, explained Michael Smeltzer, the retired founder of the UC2B network in Urbana-Champaign, Ill. Demand aggregation possibilities are diferent for the two approaches. With a single network, an operator can aggregate demand by keeping as much trafc as possible inside the network and minimizing the number of connections to the public Internet. Because intranet communications incur no marginal cost and because serving more customers via a single Internet connection allows for higher oversubscription rates (based on statistical multiplexing), this approach can signifcantly reduce transport costs, Smeltzer said. Copper networks, because of their distance limitations, must be oversubscribed in each neighborhood (that's why DSL and cable can't always deliver their advertised speeds). However, fber doesn't have the same distance limitations, so oversubscription in fber networks can be managed at a much higher level. With an all-fber network, trafc for a community of 150,000 can be aggregated at just one or two core locations and still deliver gigabit speeds reliably to each customer. Operating multiple networks over the same infrastructure – which is the approach UC2B took – requires more fber strands and more network engineers than operating a single network. However, with multiple networks, connected organizations can operate independently, in efect serving as their own ISPs. Tough this approach reduces the possibilities for demand aggregation in network operation, it enables demand aggregation during the network planning stage. UC2B fnanced its network build by selling 11 IRUs (long-term fber leases), and the proceeds from the IRUs served as the matching funds UC2B needed to obtain a BTOP award. Each IRU owner now operates a separate network, and UC2B's only responsibility to those owners is to keep the fber operational. Hovis explained that an IRU, which usually involves a 20-year commitment, is a bankable investment for a network builder. IRU agreements may cover either fber strands or wavelengths – Craig Settles, Gigabit Nation: Every year, I survey economic developers and ask whether they have plans that involve broadband. Every year, a third of them say they don't understand why that's important. That limits an area's economic success. If your economic developers don't understand why broadband is important, you're in trouble. Economic developers can market a broadband network as a proof of a community's commitment to its future. They can also train businesses to use the new technology. Finally, setting up hacker spaces is an inexpensive way to sell the vision and to create entrepreneurs. Be sure to publicize successes! Fitzgerald agreed, pointing out that wireless channels became saturated as more devices were added. "It's a challenge to provide gigabit across the spectrum," he said. "You need every tool in the toolbag." Te moderator, Richard Holtz of InfniSys, asked whether speed was users' only criterion for broadband quality or whether characteristics such as latency and jitter afected user experiences. Panelists agreed these qualities were important, especially for applications such as VoIP and gaming (networks with long latency "don't have that gigabit feel," said van Oppen). Tey noted that data compression and distance from a server could add signifcantly to latency. Locating content closer to users could reduce latency and thus improve user experiences, Scifres said. "I think we'll end up with regional content delivery networks. Tere's great latency in cities with big peering points. Now we're moving content closer to the edge. We're going to see a larger diference in quality between the big guys and the small guys." Van Oppen agreed, saying, "You can't be at scale unless you're in a lot of places. You can't achieve scale at the building level. Tere's an optimal tradeof between the number of people and the distance to the server." Scifres added, "Jitter is the bigger technical problem; it can cause an application to disconnect you. It's like chasing gremlins!" Why do college students, in particular, need gigabit speeds? Many don't subscribe to traditional pay-TV services and rely for entertainment on high-defnition, over-the-top video, panelists said. In addition, students take online classes and participate in video chats. Tey store data in the cloud. However, more exciting uses of bandwidth are still to emerge. As van Oppen said, "Tere won't be a gigabit learning application until all students have a gigabit." Aggregating Network Demand BBC_May14.indd 56 5/29/14 9:18 AM