Tài liệu The optical last mile doc

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Tài liệu The optical last mile doc

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· · · · · · · VIRTUAL ROUNDTABLE Networld+Interop, Atlanta, Fall 2001 Where will it lead us? last mile The To assess the issues and opportunities optical technologies and networks bring to end-users, we invited six leading experts to our semiannual roundtable dis- cussion, scheduled for Sept. 11, during the Networld+Interop show in Atlanta. Unfortunately, that give-and-take session had to be cancelled. In its place, we created a virtual roundtable on “The Optical Last Mile,” with our original panel of experts participating via e-mail, resulting in this interesting and informative dialogue on the optical revolution. Is the optical last mile really necessary? Why or why not? Sandra McWilliams: Fiber is the only available me- dium that achieves the optimal bandwidth, reliability, flexibil- ity and security required by today’s enterprises. As the way we conduct business contin- ues to evolve, new video and data applications will tax the limits of existing infrastruc- ture. Advancing the optical last mile is a proactive, pragmatic approach to the imminent growth of bandwidth demand. Mark Fishburn: Sep- tember 11th obviously mag- nified many market trends already in place, but may accelerate business benefits for the high-speed access market. Many pieces to the puzzle—increased demand for home entertainment to upcoming technology and metro-focused service provid- ers—make delivery of that fiber economical. Layoffs will presumably lead to an increase in SOHOs looking for low-cost, high-speed connectivity. Cüneyt Özveren: Given a cyclical economy like this one, it becomes very difficult to scale IT departments up and down as market conditions change. A solution for this problem is outsourcing IT requirements. Optical last mile enables a high-bandwidth access to enterprise networks, which, coupled with quality of service, enables application service providers to offer outsourced IT services. David Montanaro: Long term, there is little doubt that the bandwidth requirements of business and residential users will surpass the ability of any other media to handle it. If fiber is the end game, why waste time and money on interim solutions now? Brendan Mullooly: The optical last mile is nec- essary in the overall scheme; however, we see it as an ethernet-based, end- to-end solution. Only fiber provides virtually limitless bandwidth, as opposed to fixed-wireless or copper- based solutions. Where en- terprise users are within easy reach of the fiber-optic infra- structure, they can benefit from virtually unlimited band- width of optical ethernet. Offerings from traditional telcos and ATM-based networks are unable to match the robust capabilities of optical ethernet in terms of flexibility, scalability, cost, bandwidth and speed of deployment. Lawrence Prior III: Customers are demanding the band- width. Optical technologies are the only way to bridge the gap between the need for bandwidth at the network edge and the Sandra McWilliams, director, fiber cable management, fiber-optic division, ADC: “The benefits garnered by optical technologies are virtually limitless if its infrastructure is designed to work with multiple technologies and grow as demands grow.” OPTICAL OPTICAL What are the challenges and concerns for enterprises considering optical technologies? Mark Fishburn, vice president—business strategy, Spirent Communications, and a member of the board of directors, 10 Gigabit Ethernet Alliance: “September 11th obviously magnified many market trends already in place, but may accelerate business benefits for the high-speed access market.” Cüneyt Özveren, founder, chairman of the board and CEO, Atoga Systems: “Given a cyclical economy like the one we are going through, it becomes very difficult to scale the IT departments up and down as the market conditions change. A solution for this problem is for the enterprises to outsource their IT requirements.” huge optical bandwidth capacity already in existence at the network core. As more bandwidth-hungry applications are de- veloped, the bottleneck between the edge and core will become more acute. For example, end-users with 11-Mbps wireless LANs are not going to be satisfied with only a 1-Mbps network connection—especially when efficient high-capacity fiber-optic networks are just a few hundred meters away. Mullooly: Oftentimes, there is a perception that opti- cal-networking projects are a bigger task than they actually are. Deploying optical technologies, such as optical ethernet, allows enterprise network managers to add computing band- width where it makes the most sense, easily add users to the network and reduce the need for specially trained IT staff to manage the network. The primary benefit from optical ethernet is that it increases the available bandwidth, while relatively reducing the cost of WAN connections— plus enabling the use of familiar and inexpensive LAN technologies and protocols, such as VLAN. Enterprise network users and LAN managers may be un- comfortable with fiber and all its ramifications, such as mul- timode, single-mode, connector types and distance require- ments. At the enterprise level, there is no need to worry because the service provider will connect the enterprise to the fiber network, providing the necessary demarcation point be- tween the LAN and the MAN, usually as simple as deploying a media converter between the two. As a result, enterprise users do not see any obvious, discernible difference because the change from one to the other is totally transparent, with ethernet running on both sides of the connection. Prior: Enterprise customers have to develop optical networks that are flexible and scalable as the technolo- gies improve. The near-term challenge will be—figura- tively and literally—to close the loop, to finish optical networks and bring benefits of optical technologies to end-users. Business custom- ers want efficiency, reliabil- ity and low costs. As de- mand for bandwidth in- creases, as more complicated applications come on the market, businesses will have to adopt new services in or- der to stay competitive. As competition grows and bud- gets contract, there will be even more emphasis on find- ing ways to connect enterprise customers to the thou- sands of miles of fiber already at the network core. McWilliams: Two scenarios exist: renovations of existing infrastructure and new construction installations. The decision between deploying optical technologies or tapping existing copper infrastructure hinges on how each solution meets cur- rent and future requirements, network compatibility, and cost. New construction lends itself to the deployment of fiber. The investment provides a vastly superior long-term solution, offer- ing maximum bandwidth capability and minimal ongoing ex- pense. Once fiber is deployed, enterprises must then choose optical technologies that best suit network requirements. Özveren: Enterprises have traditionally relied on very high levels of interoperability. Optical technologies have not reached that level yet. Enterprises planning to use optical technologies in their networks now should be will- ing to commit to one vendor once they make their choice. Fishburn: As a supplier of performance analysis and service assurance solutions, we are connected to all the individual competing technologies—DSL, cable modem, PoS, ethernet to 10GbE, wireless technologies and the applications that run over them—MPLS, voice over IP, QoS, Internet applications. Certainly, bringing these new products to market faster gives a sense of optimism that the technology can be deployed in a reasonable time frame. Montanaro: One view is “build it and the applications will come.” The huge pipes that fiber could support would create dramatic differences in the way we do business. Imagine what a real-time, full motion, HDTV-quality conference system for meetings and education could do for your business. This is perhaps even more compelling after recent events. McWilliams: The business climate is changing. Many busi- nesses are cutting operating costs. Videoconferencing, shared data files and online applications are part of the new business paradigm. The trend toward a dispersion of employ- ees, decrease in travel and re- liance on online applications has opened the door for inno- vative technologies that allow leveraged assets to produce best value results. The benefits gar- nered by optical technologies are virtually limitless if the infra- structure is designed to work with multiple technologies and grow as demands grow. Look for DWDMs to allocate specific wavelengths for individual customers; test access to slice main- tenance costs and preserve network integrity; and optimal pro- tection, scalability and reliability to finally reside at the desktop. Özveren: Coupled with quality-of-service guarantees, band- width allows enterprise applications to be outsourced completely. This is a win-win scenario for carriers and enter- What can be done with the bandwidth that optical will make available? · · · · · · · VIRTUAL ROUNDTABLE Networld+Interop, Atlanta, Fall 2001 prises, since—on one hand—enterprises get to spend money incrementally as opposed to investing in large IT infrastruc- tures. They can adjust the “volume” of services they purchase as their needs change. This is also a win for the carriers, since it increases the revenue stream they get from their customers. Fishburn: The extension of high-speed core network- ing, provisioned by metro providers, will be one-half of the delivery model for data transport. The other is the extension of ethernet-over-fiber services to the last mile. The ethernet in the first-mile initiative—it’s the last mile for the service providers, but the first mile for the user— had its inaugural meeting as the IEEE P802.3ah task force in October. The 802.3ae committee has focused on extend- ing high-speed networking at ethernet costs to the 10-Gbps MAN/core network. Now, 802.3ah will focus on low-cost delivery of high-speed ethernet to the office and residence. Mullooly: Today, most applications do not use all the available bandwidth delivered by fiber. Most companies find that one T-1 line at 1.544 Mbps is ample for their needs and, if more is needed, additional T-1s are added. The difference is substantial in comparing the cost of a T- 1 with a 10-Mbps optical drop at a location. While the use of 100 Mbps or 1000Base-LX is rare for typical enterprise users, it is suitable for applications where substantially more bandwidth is required, such as video-on-demand, high-end multimedia, remote storage networks and vertical applications, like telemedicine, healthcare and printing. Prior: The obvious applications involve the conver- gence of voice, video and data. The one constant in every new business application is a need for greater bandwidth. What’s less obvious is the mission of bridging the explod- ing bandwidth demands of the LAN with the capacity of the network. Certainly, the recent tragedies brought into focus teleconferencing, storage area networks and disaster recovery—all bandwidth dependent—and many businesses now see them as essential. Fishburn: Bringing the low-cost ethernet business model to the metro network will be a key enabling link from the edge of the network to the overprovisioned core. Key factors will be price and availability—and will ethernet in the first mile be deliverable anytime soon. McWilliams: Look for proven technology from a proven company. Today’s turbulent financial environment is unfor- giving; vendors with exceptional records of quality service must be chosen. Free-space optics (FSO) is a promising, but relatively unproven, technology. Poor propagation conditions, physical obstruction, and security will always pose realistic threats to the integrity of the free-space signal. Because of these uncertainties, land-line backup systems will need to be available, negating any positives gained with the technology. Prior: Experience is invaluable. Look for suppliers who have real customers in the market. Ask for references. Is it real or “in development”? The best test is to see if the supplier can drop ship equipment today. Too many suppliers claim general availability, then keep you waiting for two quarters. The market will sort this out in a very Darwinian way. I would also look for suppliers with strategic partners who can bring expertise and experience to the table beyond their own company’s prod- uct. With free-space optics, if a business moves, the equipment can be redeployed, making FSO a much more efficient long- term solution than other technologies. Montanaro: Surveys show that customers value com- pany performance and technology in the purchase of network gear. Most new customers are interested to find out who else uses your gear; therefore, existing customer relationships are very important. Regarding free-space optics, we’d recom- mend FSO where short turn-up time and high bandwidth are most important. For cases in which higher reliability is most important, we would stick with a land line. Özveren: Most important is reliability. Since optical tech- nologies are relatively less mature, certain technology choices by some vendors may be less reliable than enterprises are used to. The second important factor is plug-and-play capa- bilities. A lot of the optical technologies require hand tuning power levels after the equipment is installed, and any changes typically require retuning the network. New technologies are becoming available that make DWDM plug and play. Montanaro: All of the above, though I’d include inertia, also. In the U.S., we have over 190 million access lines. A ball that big takes time and a lot of effort in the three areas identified to start moving. I’m afraid that progress sometimes takes longer than the media or the technologists have the patience for within the access arena. DSL is a good example. Özveren: Technology is not a barrier, since some vendors have shown that this can be done with the equipment that they have been shipping. Economics is typically not a barrier either, since a converged device which incorporates multiple devices will typically cost less than the combined cost of all those devices, and result in less operational expenses, since it is much easier to manage one box. The barrier is really politics. Enterprises and carriers have developed separate or- ganizations internally for different layers of the network. A converged solution requires buy in from all these in order to be accepted into the network. Faced with financial challenges, most enterprises and carriers are reorganizing to remove mul- tiple layers. Once these layers are removed, it will be much David Montanaro, CEO/chairman of the board, NEC Eluminant Technologies Inc.: “One view is ‘build it and the applica- tions will come.’ The huge pipes that fiber could support would create dramatic differences in the way we do business. Imagine what a real-time, full motion, HDTV-quality conference system for meetings and education could do for your business.” What should be considered when choosing an optical supplier? When deciding between hard-line connections vs. free-space optics? · · · · · · · VIRTUAL ROUNDTABLE Networld+Interop, Atlanta, Fall 2001 What is preventing converged networks: technology, politics, economics? Most large U.S. cities have one or more optical metro networks. Will more networks be built in these Tier 1 cities? When can most Tier 2 and 3 cities expect optical ser- vice? How will the growth of these networks impact costs to the end-user? and currently, the unsteady market and a reduction of competitors has allowed service providers to remain cau- tious about deploying optical metro networks. Montanaro: You would be hard pressed to find a U.S. town of more than 25,000 that did not have some type of fiber deployed in the ground. Chances are it belongs to the local ILEC and is being used to serve digital loop carriers, or maybe a large business. Trouble is, there may not be enough businesses to attract competitors for the ILEC. Mullooly: Supply and demand will rule the prolifera- tion of networks. In cases where fiber is not already in- stalled, the upfront cost to lay these networks is exorbitant. In most Tier 1 cities, a fiber glut exists. Less expensive, faster and more flexible than traditional telephone networks, optical ethernet provides the bandwidth and the distance that most users desire. Where the fiber network resides close to the enterprise network, fiber to the business makes more sense, with service providers using media converters to serve as the optical access point to connect the LAN to the MAN. In some Tier 2 and 3 cities, fiber networks are being deployed today because of specific demand and an existing infrastructure to support the network. Most Tier 2 and 3 cities do not contain existing networks, which reduces the need to deal with network integration issues. Service pro- viders such as EtherLECs are investigating the possibility of building their optical metro networks in these cities that will provide service at a competitive price. In those cases where the use of fiber is cost-prohibitive, it makes more sense to deploy microwave or wireless for the last mile. Prior: The rollout of optical networks is continuing, despite the much-publicized slowdown in the market. History has shown that short-term economic forces won’t stop the natural progression and adoption of technologies that really make sense. With more competition and advances in long-haul tech- nology, more small cities will soon receive optical capabilities. The problem will be finding cost-efficient and fast ways to get that bandwidth to end-users and to complete networks where it will not be economically feasible to lay fiber. That’s where free-space optics comes in. If the networks can reach them, end-users will be the biggest beneficiary of this optical growth. Not only will they get the bandwidth they crave, the services will become increasingly affordable. Lawrence Prior III, CFO, LightPointe: “History has shown that short-term economic forces won’t stop the natural progression and adoption of technologies that really make sense.” Brendan Mullooly, director of European operations, IMC Networks: “Oftentimes, there is a perception that optical-networking projects are a bigger task than they actually are . . . At the enterprise level, there is no need to worry because the service provider will connect the enterprise to the fiber network.” · · · · · · · VIRTUAL ROUNDTABLE Networld+Interop, Atlanta, Fall 2001 easier to remove the layers in the network, as well. Prior: Conflicting standards, self-interests and cutbacks in budgets have certainly slowed the rollout of all-in-one networks. But convergence is happening. Recently, in Manhattan, we experienced firsthand that the demand is there. One of our partners actually gave up its own VoIP equipment to help out a customer who was looking to restore its network using FSO links. Mullooly: With converged networks, technology definitely plays a role because it is difficult to integrate a variety of different protocols all into one network. Coupled with the complexity of different vendors’ respective hardware and soft- ware solutions, it becomes an expensive and time-consuming proposition to achieve true convergence. Optical ethernet elimi- nates many of the challenges because of the support of the standard by many vendors and their solutions. The economic landscape is changing with the advance- ment of metropolitan optical ethernet networks. The pro- liferation of ethernet service providers in Europe and the U.S. has further broken down this barrier. These ethernet service providers, EtherLECs, have built their networks from scratch by renting fiber from other providers using a simple architecture. The proposition of EtherLECs is to provide 10 Mbps or 100 Mbps at the same price of a typical T-1. As a result, EtherLECs build lower-cost net- works that make efficient use of the MAN bandwidth. The provisioning of optical ethernet connectivity to corpo- rate customers is now well established. The speeds offered— 10, 100 or even gigabit—can be utilized by larger customers for hosting multiple servers, SANs or even internal voice- over-IP traffic. Applications that can utilize the bandwidth provided by optical connectivity are well established. McWilliams: Their deployment depends heavily on the well-known theory of supply vs. demand. Service provid- ers will hesitate to build metro networks until demand for optics intensifies and competition poses a significant chal- lenge. When this happens, end-users will reap the ben- efits and avoid much of the costs. It is a waiting game, Reprinted from Communications News , November 2001 Copyright © 2001 by Nelson Publishing Inc. • www.comnews.com . transport. The other is the extension of ethernet-over-fiber services to the last mile. The ethernet in the first -mile initiative—it’s the last mile for the service. If the networks can reach them, end-users will be the biggest beneficiary of this optical growth. Not only will they get the bandwidth they crave, the

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