Our society is increasingly dependent on the Internet for instant access to information. Broadband access can have a very strong positive impact on society. The US is lagging behind in providing inexpensive broadband access to its citizens. Research is needed to develop next-generation broadband access technologies which will lead to new competitive services and applications. Novelty: This project is creating new knowledge on the design, deployment, and operation of the novel Long-Reach Broadband Access Network (LR-BAN) architecture, resource-allocation algorithms, and network evolution to accommodate traffic growth. Broader Impact: This project is enabling US researchers to lead the development of next-generation Broadband Access Networks. This comprehensive and integrated research and education project should enhance our nation's educational infrastructure through student training and influence the US telecom industry with its findings.
Specifically, this project is investigating novel network architectures, protocols, and algorithms to design and efficiently operate next-generation broadband access networks that can provide extended coverage across local and metropolitan regions in telecom networks. The project is developing efficient methods for extending the coverage of today?s Fiber-to-the-Home (FTTH) networks from their 20-km limit to 100 km and beyond by exploiting wavelength-division multiplexing passive optical networks (WDM-PONs) to serve a large user base, leading to the Long-Reach Broadband Access Network (LR-BAN). The LR-BAN architecture can effectively decrease the number of Central Offices in a telecom operator's network and reduce its Operational Expenditure. This project is investigating various LR-BAN architectural options (such as ?ring-and-spur? architecture); methods to flexibly allocate bandwidth on demand to users with a diverse set of requirements (such as ?multi-thread polling?); and methods to evolve the network toward future reliable broadband applications and technologies.
Modern society is becoming increasingly dependent on the Internet for instant access to information. Since traditional access networks such as Digital Subscriber Loop (DSL) and Cable Television (CATV) are not scalable solutions to provide high bandwidth and high-end services, Fiber-To-The-Home/Business (FTTH/B) is emerging as a very important broadband access technology to deliver the promised bandwidth and services. Passive Optical Network (PON) is the most effective FTTH technology, and it has witnessed huge growth around the world. An important goal of any communication network is to reduce its operational cost (OpEx), and one way to achieve this is to lower the network’s number of active sites. The PON is already very good in this regard because it eliminates the power supply along the fiber path from the telecom central office (CO) to end users, but further reduction of active sites can lead to larger distances to be covered by the access network, leading to even lower cost per user. Long-Reach Broadband Access Network (LR-BAN) is a very cost-effective solution for future broadband access networks. LR-BAN extends the coverage of PONs from the traditional 20 km range to 100 km and beyond by exploiting optical amplifier and wavelength-division multiplexing (WDM) technologies. Compared with traditional PON, LR-BAN consolidates the multiple optical line terminals (OLTs) and central offices where they were located, and by providing extended geographic coverage, LR-BAN combines optical access and metro networks into an integrated system. Note our proposed "ring-and-spur" architecture for the LR-BAN, which "reuses" the "ring" structure of the metro network (and hence provides fault tolerance for a single fiber cut) while each traditional PON segment is a "spur" from the ring. Intrinsic Merit: This NSF project has created new knowledge on the design, analysis, and optimization of novel system architectures (both hardware and software), network protocols, and software algorithms for building and operating the LR-BAN, i.e., the next-generation of telecom access network, and its enhancements to also include integration with wireless and copper access technologies. In particular, novel methods have been developed for the LR-BAN architecture, its resource-allocation algorithms [such as "multi-thread polling" which can overcome the relatively long distance (and hence the "control loop delay") between the telecom central office and the end user], and its energy-efficient design and operation; integrated wireline-wireless access network architecture; integrated optical-coaxial access network architecture; performance of services such as streaming IPTV over optical access networks; as well as seamless network evolution to accommodate traffic growth. Also, an experimental prototype of a wireless-optical broadband access network (WOBAN) has been developed on which tests and experiments have been performed to demonstrate the various properties of the proposed architectures, algorithms, and methods. Broader Impacts: This NSF project has supported the research of seven PhD students (five completed, including one visiting from Europe for a year) and three UG students. One PhD alum is at Brocade, Inc., working on optical access network solutions, the topic of his PhD research. Another PhD alum became Co-Founder and Architect of Ennetix, a startup company incubated at UC Davis and developing products for energy conservation in networks. A Visiting PhD student, upon graduation, is working as a postdoc in Italy on FTTX network architectures. Another alum finished his PhD on energy-efficient access networks and is now working at Cisco Systems, Inc. on datacenter networks. A fifth PhD alum is now a postdoc at Trinity College Dublin. Two PhD students trained by this project are continuing their research activities which started with collaborations from HP Labs and Huawei (on optical-coaxial access network integration). Research from our NSF projects on broadband access over the past 9 years has caught the attention of Nokia Siemens Networks, ETRI Korea, Teknovus, Hewlett-Packard, and Huawei, all of whom have supported some of our students for research collaborations. Several international collaborators have also been attracted to our project, from institutions such as Indian Institute of Technology, Kharagpur, India; Universita Politecnica Catalunya, Spain; KTH Sweden; Beijing University of Posts and Telecommunications, China; and China Academy of Telecom Research. Very good survey articles by us on LR-BAN and energy efficiency in telecom networks have appeared in IEEE Communications Surveys and Tutorials. Several of our other papers from this project are tutorial oriented and published in IEEE Communications and IEEE Network. The PI serves as Editor of Springer’s "Optical Networks Book Series" which publishes books on optical networking, including Broadband Optical Access. PI Mukherjee Co-Guest-Edited the September 2012 IEEE Communications Magazine Special Issue on "Service Interoperability in Ethernet Passive Optical Networks (SIEPON)". PI Mukherjee also Co-Guest-Edited the May 2012 Centennial Issue (vol. 100) of the Proceedings of the IEEE on "The Evolution of Optical Networking". Thus, the role of this NSF project has been excellent.
