Cisco® Cable IP Next-Generation Network (NGN) transport solutions provide evolving end-to-end transport network solutions, specifically designed to enable cable operators to meet the growing demand, stringent requirements, and multiservice needs of today's cable networks. As cable operators expand their suite of voice, video, and data services, it becomes increasingly clear that a single, converged transport infrastructure is the most effective and efficient way to help them scale to meet these demands.
Cable Operator Challenges
As cable operators work to grow their subscriber base and average revenue per user (ARPU), they are facing increasing pressures. With increased popularity and explosive growth in bandwidth requirements for video services-because of video on demand (VoD), growing broadcast channel lineups, and the increasing popularity of video downloads from the Internet-cable operators need a cable infrastructure capable of scaling to meet these growth demands. Beyond bandwidth demand, other challenges include:
• Supporting the rapid expansion of digital voice and high-speed data services
• Operation and maintenance of multiple networks, supporting different services
• Integration of different network components from different equipment vendors
• Increasing network capacity while still delivering reliable, high-quality service to existing subscribers
• National and regional competition in voice, video, and data service delivery
Technical challenges must be met with technically effective solutions, while at the same time improving capital and operational efficiencies, to keep service costs from escalating. Failure to address these important issues carries large down-side risks, including:
• Erosion of market share
• Missed revenue opportunities for new services
• Higher subscriber churn rates
• Longer term risk of market displacement
• Higher capital and operational expenses (capital expenditures [CapEx] and operating expenses [OpEx]), reducing profitability
Additionally, as service providers expand service offerings, network operations become increasingly difficult. As more network elements are added to the network, complexity increases. This reduces the efficiency and effectiveness of the network and results in higher costs and service quality degradation.
At the same time, the network must be built for unparalleled reliability, and it must incorporate mechanisms to help ensure a high-quality subscriber experience by minimizing packet loss, jitter, and latency. In addition, the network must provide the flexibility to support emerging applications.
Older networks, not capable of scaling and reliably supporting this need for dramatic growth and application flexibility, are in need of transformation.
Cisco IP NGN
Enabling this transformation is the Cisco IP NGN. IP NGN, which is built on a three-layer network model, which includes the network (transport) layer, the service (framework) layer, and the application (services) layer. These three layers are combined into one closely integrated operational layer, which outlines and details the transitional path from service provider to experience provider and opens the door for new, connected life services. See Figure 1.
Figure 1. Cisco IP NGN Architecture
The need for scalable and reliable video delivery is today's biggest driver of network expansion. Cisco video solutions are a primary component of the Cisco IP NGN. They are designed and tested for optimal delivery of multiple video services-including VoD, broadcast video services, and switched digital video (SDV)-as well as digital voice solutions and high-speed data (HSD) services. Each service possesses unique characteristics and places unique demands on the transport network supporting it. The ability of Cisco to provide service separation and high quality of service (QoS) over a converged transport architecture helps ensure high customer quality of experience (QoE), enabling cable operators to help ensure customer satisfaction across network applications.
Cisco Cable IP NGN Transport Solutions: Enabling Convergence At The Network Layer
Operating a single, converged IP infrastructure offers tremendous advantages, including:
• Significant network simplification
• Reduction of CapEx and OpEx through converged architecture
• Efficient, scalable delivery using high-performance IP unicast and multicast technology
• Bandwidth savings on HFC plant using SDV delivery
• Highly available, fully redundant video delivery
• Efficient QoS and QoE capabilities
Core and regional transport networks rely on several components, including core routers, edge routers, and optical transport. Cisco offers best-in-class platforms in each of these product areas, with the following products:
Cisco Carrier Routing System (CRS-1) core router: This carrier routing system offers continuous system operation, service flexibility, and system longevity. Powered by Cisco IOS® XR Software, it is designed for always-on operation while scaling system capacity up to 92 Tbps.
Cisco 7600 Series Routers: These routers offer integrated, high-density Ethernet switching, carrier-class IP/MPLS routing, industry leading multicast capabilities, and line rate 10-Gbps interfaces.
Cisco Optical Multiservice Transport and Provisioning Platforms (MSTP and MSPP): These optical platforms support data transport rates from 155 Mbps in SONET/SDH, and up to 40 Gbps per channel in DWDM, with 32 C-Band and/or 32 L-Band channels of user-configurable passthrough or add/drop traffic functionality.
Video Services and Network Infrastructure
Of all the services cable operators offer, video service delivery is by far the most challenging. Not only do video streams require a large amount of bandwidth, but also they require virtually zero packet loss, are jitter and latency sensitive, and must scale to a very large number of subscribers. Figure 2 shows video distribution as part of a converged network architecture.
Figure 2. Cable Video Reference Architecture
Cisco Value Proposition
Following the Scientific Atlanta and Arroyo acquisitions, Cisco can provide a complete end-to-end cable solution, utilizing best-in-class components, including:
• Headend equipment
• Core and edge routers
• Optical transport
• Service control engines (SCEs)
• Quadrature amplitude modulators (QAMs)
• Cable modem termination systems (CMTSs) and cable modems
• Content delivery systems (CDSs)
• Set-top boxes (STBs)
Having "all the pieces" provides tremendous advantages because it enables extensive end-to-end testing for a complete cable multiservice solution. Targeted application testing for voice, video, and HSD across the entire network greatly enhances network performance:
• Multicast performance capabilities on both CRS-1 and Cisco 7600 Series platforms enable large-scale video replication and distribution.
• Improved network reliability, with solution focus on source diversity, path diversity, and path resiliency, helps ensure consistently high QoE levels.
• Service separation on a converged core permits independent focus capabilities on each service.
• QoS features and redundancy capabilities at L1, L2, and L3 help ensure high-quality service delivery. Strict ingress-to-egress QoS controls help ensure that video traffic is given top priority, with minimal loss, latency, and jitter, all important for quality video delivery.
Integration testing in Cisco labs enables additional benefits, including accelerated deployment schedules, reduced costs, and reduced frustration. This means Cisco designs can be integrated much more easily, reducing required test work by cable operators, saving them both time and money:
• Faster network buildouts
– Simplified deployment using comprehensive design guides
– Reduced test times
• Capital expenditure reduction
– Fewer devices are required due to the elimination of parallel networks.
– Superior performance and throughput reduce the number of devices required.
• Operational expenditure reduction
– There are fewer devices to monitor due to the elimination of parallel networks.
– Network and service management products (for example, Broadband Access Center for Cable [BACC] and Cisco Network Registrar) ease management.
Summary
Many vendors offer point products for particular network functionality. Cisco offers a truly complete portfolio, with extensively tested complete, end-to-end network solutions. As cable operators continue to grow their networks, subscriber base, and revenue generating services, they can rely on Cisco, as both a vendor and a partner, to provide complete, cost-effective, scalable solutions to help them reliably grow their business and meet increasing subscriber demands.
For More Information
The Cisco Cable IP NGN Transport solution for cable operators is built on the interconnection and integration of multiple Cisco products across multiple technology platforms, including core routing, edge routing, and optical transport platforms. These platforms support needs in backbone, regional core, and regional distribution networks. Links to individual technology platforms can be found below:
