NEXT GENERATION - CABLE ACCESS NETWORK AN EXAMINATION OF THE DRIVERS, NETWORK OPTIONS, AND MIGRATION STRATEGIES FOR THE ALL-IP NEXT GENERATION – CABLE ACCESS NETWORK Authors:M. Emmendorfer, S. Shupe, D. Cummings, T. CloonanContributors:Z. Maricevic, M. Schemmann, B. Dawson, V. Mutalik, J.Howe, A. Al-Banna,and F. O'Keeffe ARRIS ABSTRACT to rise at an alarming rate. Cable Operators like the United Kingdom's Virgin The Cable Industry is facing a Mediaannounced in April 2011 an Internet decade of unprecedented change in the areas speed trial of up to 1.5 Gbps downstream of video and high-speed Internet services. and 150 Mbps upstream [1].The cable This change,driven by competition and competitor Verizonis reportedly exploring consumer demand, will transform the cable plans to upgrade its FiOS system to XG- network end-to-end. This paper will focus PON, the 10 Gbps downstream and 2.5 entirely on what we are calling the Next Gbps upstream technology [2]. New Generation Cable Access entrants in the video distribution space are Network,examining the business drivers, capitalizing on the network investments network options, and migrations strategies in made by the telecom industry, forcing the access layer of the data and HFC changes in their video delivery network as network to provide more IP-based capacity well as the high-speed data network. A key to and from the home. The document covers challenge the cable industry will face in the in-depth the core business drivers and the future will be offering PON-like IP-based technical options spanning animmense area capacity in the downstream and the of network disciplines and technologies, upstream to consumers, while leveraging thus we have included a comprehensive their existing coaxial network. executive summary at the conclusion of the report. Some of the most often asked questions by cable industry forward-looking The analysis includes the allocation planners reflect the key challenges the of existing spectrum and possible future industry is facing for this decade and spectrum expansion to accommodate beyond. Some of these challenges and consumer demand. Cable Operators and questions include: 1) How long willthe their competitors are enabling consumers to current spectrum split and 500 HHP change their viewingoptions for video nodelast? 2) What are the network services and the usage of the high-speed technology and architecture options and Internet network.In the area of high-speed what are the pros and cons? 3) How long Internet service, competition and consumer will each of these new network architecture demand is increasing the service speed tiers options last? 4) What are the financial offered,and network traffic usage continues impacts of the options?5) What are the best each network architecture and technology, ways to leverage previous, current and so industry leaders may make an informed future investment? decision.These topics under consideration comprise several network technology This paper will seek to provide some disciplines, which are often separate areas of visibility and answers to these questions and concentration. This paper is by no means key challenges. The paper will focus conclusive; some of the areas under entirely on the network aggregation and examination have not had significant study access layer including the CMTS, HFC and or have the absence of products to home network. This paper will provide sufficiently examine and forecast the best some predictions for service tier and traffic path.There are also timing considerations growth, which serve as the drivers for and business trade-offs that will need to be network capacity and network utilization considered. forecasts that are used to predict the timing of the network changes and investment. We INTRODUCTION – PLANNING FOR THE NEXT will examine the network technology and GENERATION – CABLE ACCESS NETWORK network architecture options from spectrum A major challenge the cable industry splits, data MAC and PHY technologies as will face in the future will be meeting the well as network architecture options. This needs of the consumer and addressing the paper will consider the capabilities of a drop competitive threats of PON/FTTH systems in upgrade with an effort to maintain a 500 all while leveraging the existing coax to the HHP service group and typical number of home. This will mean significant changes in actives and passivesto determine the the use of network technologies, spectrum viability and impact for upstream spectrum allocation, and overall network architectures. Planning for the Next expansion. The funneling effect must be Generation – Cable Access Network is considered in the analysis for the NG Cable extremely difficult as this spans across Access Network. The paper provides several network disciplines within the cable analysis and comparison of some of the industry and even technologies outside or network elements under consideration. The not widely deployed in cable, such as PON, paper introduces a term called Digital Fiber Wireless, and EoC. The span of network Coax (DFC) as a next generation technology disciplines also reaches into the network elements and underlying sub- architecture, which may augment the HFC systems such as MAC layer, PHY layer, media conversion style architectures that HFC optical transport components, as well utilize centralized data access/aggregation as several access radio frequency layer equipment. technologies end-to-end such as amplifiers, passives, and coaxial cable. What is proving We considered a couple of migration to be a significant challenge is the increase strategies as more viable than others and dependency between all of these while not picking a particular end-state traditionally separate network disciplines as approach, our position is to examine the part of the new cable access network architecture. In years past these options and document the pros and cons of technologies functioned in many ways independent of one another. This next Flexibility to accommodate generation cable access architecture will incremental allocation of likely migrate to more IP based spectrum in IP/Bandwidth for smooth transition the downstream cannibalizing existing strategy and pay as you grow or just technologies which are non-IP based in time network planning creating a more efficient and competitive DOCSIS Backwards Compatibility network transport platform to compete with leverages MAC/PHY channel PON on the downstream and simply have bonding groups previously deployed the versatility of IP based technology. The and occupying spectrum yielding upstream will need more spectrum and it is investment protection delaying or the overall spectrum allocation and avoiding significantly costly placement of this new spectrum, whichwill approaches to find new spectrum have the greatest impact on the cable Investment protection by re-using industry for decades to come. spectrum already in service, DOCSIS, HE lasers/receivers, and The challenge we have is predicting CPE (STB/Data) as much as possible the timing of the change in the network and Leverage network passives the most how long each change will last. numerous OSP element Additionally and most importantly what are Avoid costly and unnecessary fiber the impacts of each of the upstream builds spectrum options that may be considered for Keep the OSP as Simple as Possible the future. This paper will provide for as Long as Possible predictions, such as the drivers for the use of Leverage High densities and the spectrum in the downstream and economies of scale upstream. The paper considers the spectrum allocation options and predicts how long Importance of Backward Compatibility each will last beginning with the current with DOCSIS 3.0 and Any Successor sub-split options and several spectrum splits which add new upstream capacity and how The authors of this paper believe that long these will last. The report provides a DOCSIS and any successor should consider technical comparison of the upstream the value of backwards compatibility spectrum options and the impacts that each has from services to overall network especially across channel bonding groups. architecture and cost. This assures previous and future investment may be applied to create a large IP based Our Goals for Next Generation – Cable bandwidthnetwork while not stranding Access Network include: previous capital investment and spectrum. Achieve upstream bandwidth The use of channel bonding leverages every requirements through this decade MHz, which are finite and not free, this is all Achieve downstream bandwidth towardsan effort to create one large IP pipe requirements through this decade to and from the home. The use of Continued versatility to backwards compatibility has benefitted the accommodate advances in cable industry as well as other industries networking technology without which use technologies like IEEE Ethernet, massive changes to the outside plant WiFi, and EPON creating consumer network. investment protection, savings,and a smooth and most importantly the spectrum migration strategy. The adoption of allocation options to forecast network backward compatibility simply allows the capacity. Then after considering the Service MSOs to delay and perhaps avoid major and Traffic growth we measured this against investment to the network such as adding the network capacity options, in the section more data equipment, spectrum, node splits, referred to as Network Utilization and or running fiber deeper. Capacity Planning. In this section we forecast the timing and duration of each Overview of Our Methodology For network step. In step four we examine Network and Capacity Planning several of the network technology and In our analysis and in the structure of architecture options under consideration. this paper we have examined the Next The Network Migration Analysis and Generation-Cable Access Network in Strategies consider all of the factors of the several steps as captured in the illustration aforementioned steps and provides some below (figure 1). As shown in the analysis of possible migrations strategies to illustration our process was to first address the competitive threats and determine the future requirements. The first consumer drivers.