ET '05
The Society of Cable Telecommunications Engineers’ Conference on Emerging Technologies (ET) in Huntington Beach, Calif., in January attracted 935 attendees looking to stare three to five years into cable’s future. (That marked a 20 percent attendance increase from last year.) It’s time to plan for the quadruple-play—or the "four-play," Paul Allen joked at ET’s keynote. "We have to internalize that things are going to be happening faster than we’ve seen in the past," the chairman of Vulcan and Charter said. Allen’s vision of cable’s video/voice/data/wireless bundle included everything from widescale rollouts of what he heard one consumer calling a "peever" (PVR, or personal video recorder) to wireless phones with the ability to receive digital TV. Allen concluded that partnerships with consumer electronics and wireless companies are keys to making the quad-play happen. "We’re in the driver’s seat going forward," he said. "We have the superior platform." Don’t be smug Liberty Media SVP and CTO Tony Werner, who moderated the opening session on competition, noted that technical innovations in silicon, digital signal processing (DSP) and storage are breaking down the walls of once natural monopolies. The upshot: new opportunities for fiber to the home (FTTH), broadband over powerline (BPL), wireless, high bandwidth over copper and high-capacity satellite. David Reed, EVP and chief strategy officer of CableLabs, discussed his paper on digital subscriber line (DSL) and Internet protocol TV (IPTV), which he co-authored with Werner. Reed noted that while cable may surpass DSL in North America by some 6 million subs, globally cable is down by 32 million. Among the top 20 countries in broadband, DSL leads cable in all but four: the United States, Canada, Hong Kong and Netherlands. "The lead is expected to widen, especially as China gets broadband," Reed said. Reed also noted that the Japanese operator J-COM (partly owned by Liberty) has launched a 30 Mbps tier that is achieving remarkable penetration rates among new subs. Along those lines, it is worth noting that Cisco Systems used the ET event to unveil a wideband protocol for Data Over Cable Service Interface Specification (DOCSIS) capable of delivering up to 640 Mbps to a single home. That sort of potential data rate could make cable’s offering comparable to the 500 Mbps per 16 gateways symmetrical that Wave 7 Optics CTO Jim Farmer said is now available through an FTTH architecture. As at previous industry events, Farmer underscored the maintenance cost advantage that FTTH holds over HFC. Whatever the actual cost structure of FTTH, operations and maintenance expenses are far from irrelevant in calculating its advantages. "This is a 30-year plant," said one Verizon official about its ongoing build, according to Farmer. More classic cases of disruptive innovation appeared in the talk on Wireless Fidelity (Wi-Fi) and World Interoperability for Microwave Access (Wi-MAX) by Sandy Teger, co-founder of System Dynamics. The municipality of Chaska, Minn., for instance, had 1,100 people sign up for a $15.95 per month, Wi-Fi broadband offering, even before the service went live. With modest investment, this town of 7,500 homes was exploiting a portable (if not quite mobile) technology that is cheap, simple and low performing, yet commercialized and amenable to rapid improvement. Problems with security, quality of service (QoS) and other issues that have afflicted wireless broadband are not insoluble. "Standards are addressing them, one-by-one," Teger said. With 160 members of the Wi-MAX Forum, all across the value chain, she predicted that mobile Wi-MAX products would appear by the end of 2006. This shift from fixed to personal communications hits cable operators hard. "We are tethered to the home; all our metrics are home-based," Teger said. Yet the number of communities where wireless broadband is being trialed or marketed is growing. "Is your city next?" she asked. As for satellites, being geostationary doesn’t mean standing still technically. Increased amplification and the use of spot-beam technology will increase the throughput and capacity, said Steven Osman, director of engineering and new service development at SES Americom. Two other approaches being explored to expand bandwidth are satellites placed between existing orbital slots ("tweeners") or piggybacked on existing slots ("toppers"). But that’s not all. Better compression and modulation, as well as the transformation of current receivers into multi-satellite, multi-frequency antennas, could all take their toll on cable. "After ’07, without converting to all-digital, cable will find DBS a strong competitor," Osman said. Wireless in a wired world "Why do MSOs care about WiMAX?" Fujitsu Principal Network Architect Jim Orr asked at the "Emerging Wireless Technologies: Friend or Foe?" session. "Realizing that the technology is in its infancy, but rapidly approaching, cable operators are taking the opportunity to use their considerable technical capabilities and market knowledge to retain customers who may abandon cable modem services for a reasonably robust wireless solution," he said. Orr explained how the IEEE 802.16 standard has been developed to fill the shortcoming of previous wireless data standards in security, RF efficiency, throughput efficiency, QoS and line-of-site limitations. Additionally, the WiMAX Forum was developed to define the implementation of this set of standards to ensure common and interoperable equipment. "WiMAX offers solutions to issues that face cable today and in the future. It is critical to participate in the rapidly maturing wireless data services market to avoid the customer loss issues as seen in the wireline market," he warned. Dave Waks, co-founder of System Dynamics, predicted that several wireless technologies would be used in the home, including Wi-Fi, UltraWideBand (UWB), Bluetooth and ZigBee, and directed the bulk of his talk toward the first two. "Over the next few years, QoS and higher speeds will enable Wi-Fi to carry voice services, standard-definition video and high-definition video along with data. UWB may replace cables as the connection between cable set-tops and digital TV sets," Waks explained. Cisco Consulting SE Manager Vince Spinelli focused on the metro side of the wireless equation. He stressed that the complimentary nature of the MSO and the mobile operator coupled with the maturation of technology make the possibilities of a converged or consolidated service provider marketplace a reality. Home, Sweet Home … Networking The Consumer Electronics Show echoed through the "How Are Things at Home?" session. Moderator Mike Hayashi, Time Warner Cable senior vice president of advanced engineering and technology, referred upfront to the recent Consumer Electronics Show: the array of HDTV sets there and the dispersion of content to multiple, portable consumer devices. "(That’s) giving a lot of our content owners heartburn," Hayashi said. YAS Broadband Ventures’ Doug Jones discussed options for extending conditional access (CA) systems in the home with digital rights management (DRM). It’s a shift from a service-based and streaming-oriented technology focused on theft of service to a more flexible, rules-based approach regarding service consumption and usage of stored content. This trend has many drivers, including the automobile. With apologies to MasterCard, Jeff Ayars, a parent and general manager of embedded players and client technologies at Real Networks, offset the hypothetical costs of transferring via Wi-Fi an episode of "Dora the Explorer" to a car-based server against the "priceless" value of averting a temper tantrum en route to grandmother’s house. As for interoperable content protection schemes that could enable such a scenario, Ayars dismissed MPEG-21 and the EURESCOM Open DRM Architecture (OPERA) and drew attention to the Open Mobile Alliance DRM 2.0, a specification in "candidate enabler phase" whose design was steered by Real Networks, Intel and others to encompass use beyond mobile phones. Using extensible markup language (XML) documents as rights objects and other standard DRM protocols, OMA DRM 2.0 powers a flexible and full-featured architecture, yet leaves some aspects of deployment up to users of the spec. Filling those gaps, said Ayars, is a group called the content management license administrator (CMLA), which would act as the root authority for OMA DRM 2.0 implementations, generating keys and sign certificates. Finally, to bridge the current gulf between CAS and DRM, Ayars pointed to CableLabs’ dynamic feedback arrangement scrambling technique (DFAST) as a workable interface. "A CMLA-licensed OMA DRM is a great candidate to test this framework," he added. New levels of storage and intelligence continue to transform the home as network edge. "Today’s PVR is just the tip of the iceberg," said Gary Hughes, director of media engineering at Broadbus Technologies. With reference to the CE show, Hughes described the emerging home media server (HMS) as a next-generation device that acquires, stores, presents, navigates and distributes content. "It all sounds rather like a home mini-headend," he said. Up until now, this device has been largely invisible to the rest of the network. Greater interaction between cable headend and HMS, however, is going to be increasingly important, Hughes said. Among other reasons, it will help optimize network resources and enable new services, such as video on demand (VOD) caching, more robust "push VOD," magazines, hyperchannels and ad insertion. Apart from DRM and video formatting, Hughes said another key challenge to firing up next-gen HMS devices is a standards-based metadata rich and extensible enough to feed multiple sources to multiple targets. The most direct feed from CES came from Paul Liao, CTO of Matsushita Electric Corp. of America (Panasonic), whose presentation included a picture of him demonstrating the transmission of HD content over a standard extension cord from server to plasma screen at the Vegas confab. That demo highlighted breaking news, namely: Panasonic’s withdrawal from the HomePlug Powerline Alliance and simultaneous launch at CES, together with Mitsubishi and Sony, of a group tentatively named the CE-Powerline Communication Alliance. The stumbling block of home networking has been digital video assets, not high-speed data. Or as Liao quipped: "The digital (home) network is a whole new ball of fish." What this powerline communication (PLC) specification—and related new chipsets—offers is total aggregate bit rate at the physical (PHY) layer as high as 190 Mbps and QoS enabled by intelligent time division multiple access (TDMA). Liao said another feature is its use of a wavelet-based orthogonal frequency division multiplexing (OFDM) rather than fast Fourier transform (FFT)-based OFDM technology generally used in PLC systems. The advantage? Superior sub-channel isolation that prevents interference, such as from amateur radio bands, without costly notch filters. Apart from this wavelet-based technology, Liao also touted MPEG-4’s high profile extension and the potential for interoperability promised by the Digital Living Network Alliance. On the DRM front, Liao contrasted the deadend of the secure digital music initiative (SDMI) with the "overnight sensation" of Apple’s user-friendly FairPlay scheme. The moral of the story: "If you try to change consumer behavior, good luck." Bandwidth management At the "Strike up the Bandwidth Management" session, Dave Large, chief technical advisor at Entone Technologies, emphasized that standard, layered architectures are necessary to support dynamic allocation of both applications and the resources needed to support them. "With a next generation network architecture (NGNA), two standard bottom layers support a third applications layer. The applications can be proprietary, multi-vendor and easily added," he explained. Nishith Sinha, ITV systems engineer at Cox Communications and Ran Oz, CTO, BigBand Networks, presented the results of technical trials that correlated increase in channel use with both program popularity and an increase in subscribers. The correlation can be modeled by a mathematical relationship known as "Zipf’s Law," which allows operators to predict the number of edge-QAM devices and QAM channels needed for various growth and subscription scenarios. TWC’s Glen Hardin showed how to avoid stranded bandwidth when standard definition (SD) and HD VOD content are processed by multiple QAM devices in the same VOD service group. Current loading algorithms may block HD content requests even though the service group has available bandwidth across a group of QAM devices. Hardin showed how allocation of the service group can be optimized by considering QoS parameters based upon bandwidth thresholds, number of sessions and data rates, in addition to the least or most loaded algorithms currently used for QAM channel allocation. The benefits of sharing QAM devices within a service can be made even more dramatic by extending the concept to multiple services. Sangeeta Ramakrishnan, technical leader at Cisco, discussed a phased approach for implementing multi-service edge devices, which begins by deploying reconfigurable QAM devices to the particular service being deployed. Later evolutions of the concept would allow a single QAM device to support multiple services simultaneously via channels configured for different services, and ultimately, via dynamic sharing of individual QAM channels. There are substantial economic benefits to such a multipurpose edge device. Per Ramakrishnan, "A shared pool of QAMs across video on demand and switched broadcast provides between 15 to 25 percent savings on edge-QAM expenses, along with a proportional savings in HFC spectrum." Just as QAM usage optimization is important to residential services, optical transport optimization is key to the business services market. Mitch Auster, product marketing director at Ciena, pointed out that although reconfigurable add/drop multiplexing (ROADM) technology originally developed for the telephone companies eliminates stranded wavelengths, it does not solve the problem of stranded capacity within a wavelength. He noted that for cable operators, optimum flexibility for business services will be provided by a platform that integrates sub-wavelength add/drop multiplexing, next generation ROADM, tunable optical add/drop multiplexers (TOADMs) and widely tunable transporters onto a common platform. Beyond multiservices, multimedia presents another dimension to bandwidth allocation. In PacketCable Multimedia (PCMM), a policy manager dynamically allocates resources to applications upon request. Complicating the picture, PacketCable allows applications to be dynamically added to a system. The dynamic capacity management program (DCAPMAN) described by Ben Bekele, senior DOCSIS engineer at Cox, is a proposal for monitoring and predicting resource needs as multimedia systems scale, preventing blocking due to insufficient capacity. Smart or dumb? During the "Smart Pipe/Dumb Pipe" session, Susie Kim Riley, founder/CTO of Camiant, said the storyline of cable network evolution goes from big to bigger to better to smart. Accelerating this latest push for intelligence have been the "party crashers"—bandwidth-hitchhiking applications such as voice, gaming, music, video and rich instant messaging. With those and other services leading to an anywhere, anything, any-format on-demand future, the need to distinguish between them has grown. "QoS is not a nice-to-have, but a must-have," Riley said. An undifferentiated network is locked into a flat-fee model, with revenues dependent on the volume of customers and fixed costs dangerously unpredictable, Malind Gadekar, senior manager, service control platforms at Cisco, added. Gadekar’s scary comparison was with the airline industry, where labor and fuel prices rise and tickets get cheaper by the month. An even closer analogy incorporating the notion of peer-to-peer (P2P) would have large numbers of overweight passengers taking up entire rows and riding from airport to airport, without ever disembarking (or purchasing new tickets)! To get smart, Gadekar advocated a gradual approach. Step one ("elementary school") is a matter of analyzing usage by different categories (subscribers, application, demographics, etc.). The next step is to "condition a network" that may be 60-70 percent filled with P2P traffic. Step three ("high school") is service differentiation: define, enforce and bill. "What this enables is for us to move from a highway to a toll-way," Gadekar said. From the perspective of a CMTS, bandwidth smarts is partly a matter of applying the right algorithms. Arris CTO Tom Cloonan ran through an example of if/then sequencing: "Is each sub getting enough throughput? If not, can capacity be optimized? If so, optimize and check. It not, then identify accessible channels. Is there spare capacity? If so, then load balance, etc." The keys, Cloonan said, are: detection of channel congestion, bandwidth boosting, load balancing and channel capacity optimization. Where today’s sophisticated CMTS technology is headed is an open question. The evolution toward an IP headend and decoupled CMTS may be underway already, but Motorola Senior Director of Advanced Technology Gerry White said that the distributed approach involves real architectural tradeoffs. "That’s not to say that it’s not a great idea," White said. But he cautions that the decoupled CMTS faces challenges in terms of timing, QoS, operations and management, redundancy, reliability and standards compliance. Beyond the topics of network intelligence and architecture looms the competitively tinged question of capacity. Given rising threats, is there enough? John Chapman, Cisco distinguished engineer (and DOCSIS protocol innovator), turned that question on its head. At 5 Gbps per fiber node, a small plant that serves 100,000 households with 200 such nodes has a capacity of 1 Tbps (that’s Terabit). By contrast, today’s analog, digital, VOD and DOCSIS traffic consumes about 19 Gbps. "Today’s HFC plant is using far less than 2 percent of capacity," Chapman said. In other words, the question isn’t capacity, but exploiting what’s there. His solution: "Rearranging the bits and mining the bandwidth." More precisely, Chapman proposes "striping" packets across multiple QAM channels, which in turn become a single logical wideband channel. In an existing CMTS (Cisco had a working demo at the conference), a wideband media access control (MAC) module interfaces with the external edge-QAM device for downstream and with traditional DOCSIS cards on the upstream. Like Cisco’s wideband protocol, Broadcom’s bonded channel approach also could play a role in the next version of DOCSIS. The key to this technology is the idea of statistical multiplexing. When unevenly distributed across separate channels, data flows are more limited than when multiplexed across a group of "bonded" channels. Broadcom’s Senior Technical Director Thomas Quigley discussed how this approach, which has precedents in the telco space, can enable increased bi-directional throughput while coexisting with legacy DOCSIS devices. The following Communications Technology editors contributed to this wrap-up: Laura Hamilton ([email protected]), Jonathan Tombes ([email protected]) and Jay Junkus ([email protected]). The ET Winners Are… Also in Huntington Beach:
