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Redback Enables Triple-Play and VPN Services for North American Next Generation Broadband Network

The SmartEdge Multi-Service Edge Router simplified network design and operations by consolidating IP edge routing, broadband aggregation, and MPLS VPNs on a single platform. The customer was able to deploy a single broadband network for both residential and business services, and enable innovative new services such as IPTV.

As one of the largest operators in its coverage area, this incumbent telecom provider offers a wide range of voice and data services to residential and business customers regionally. In recent years, increasing competitive pressure from alternative carriers and commoditization of traditional services has prompted incumbents such as this operator to seek new sources of revenue. The company needed a strategy to accelerate their broadband initiative and expand their service portfolio. The SmartEdge Multi-Service Edge Router enabled the operator to accomplish this by optimizing its network architecture to deliver triple-play and VPN services while gracefully migrating legacy access infrastructure and enhancing existing services.

Situation
With over 3.5 million high-speed Internet customers and a large base of deployed fiber, this company is one of the leading operators in the broadband industry. While overall broadband adoption is increasing, eroding revenues from traditional telecom services and intensifying competition from cable operators has driven this provider to explore practical strategies to enhance its service portfolio and pursue new revenue generating opportunities.

Part of this provider’s broadband strategy involved upgrading its DSL facilities to support ADSL2+. With potential speeds of up to 24Mbps and connectivity over an Ethernet-based network rather than legacy ATM backhaul, the deployment would enhance availability and performance of the company’s broadband access offering and provide a complementary solution to the ongoing fiber deployment initiatives.

New services such as triple-play and VPNs for consumers and businesses offer the promise of attracting new subscribers, attaining higher service margins, and increasing customer retention. In order to capture this value, this operator would have to ensure a high quality of experience for its customers and implement a cost-effective service delivery network.

Solution
In order to remain competitive, this operator had aggressive plans to upgrade the majority of their broadband access infrastructure to support speeds of 12Mbps in the near-term, and eventually move to 24Mbps and beyond using DSL bonding and Passive Optical Network (PON) technology. The operator needed an extremely scalable and versatile multi-service edge routing platform to accommodate their growing needs and enable innovative new services.

In conjunction with infrastructure enhancements, the company’s service strategy involved ramping up voice over IP, IPTV, and other multimedia applications for the entertainment-focused consumer market, and VPN services for the business market. Redback’s SmartEdge MSER enabled the provider to address all of these priorities with a highly flexible, scalable, and cost-effective service delivery platform.

Network Evolution
The provider’s access infrastructure consisted of both legacy ATM-based DSLAMs from earlier generations of deployment, and newer IP-DSLAMs which were part of the overall infrastructure upgrade. The SmartEdge MSER enabled this operator to directly connect both types of DSLAMs and offer the same subscriber management policies, QoS treatment, and overall service creation capabilities across the entire customer base. This supported both the coexistence and graceful migration of users served by multiple generations of access equipment.

The port density and session scalability of the SmartEdge MSER enabled this operator to adopt a fully converged aggregation model, where DSLAMs were directly connected, rather than consolidated with an intermediate aggregation network. Elimination of additional network elements reduced costs and complexity while creating a more manageable network with deterministic service delivery.

Service Enablement
As seen in the adjacent figure, this provider’s broadband access customer base consists of retail Internet users, wholesale DSL subscribers, small-to-medium sized businesses, and enterprise customers. With the exception of large enterprise customers, the majority of the customer base receives services via some form of DSL. All of these services are offered over a single broadband network, with the SmartEdge MSER serving as the central service control point.

Retail customers obtain Internet access by first establishing a PPPoE session to the SmartEdge MSER. Once the user is validated via RADIUS server, the SmartEdge platform routes the user traffic through the backbone network and to the Internet.

Wholesale customers share the same access infrastructure as retail customers. Their traffic may be aggregated on the same SmartEdge MSER serving retail customers, but rather than terminating the user session locally to authenticate via RADIUS, the SmartEdge MSER establishes an L2TP tunnel to the appropriate third party ISP. The wholesale user’s traffic is passed transparently to the upstream ISP to obtain Internet access or any additional third party IP services.

Both large enterprises as well as small-to-medium sized businesses are demanding higher throughput and greater reliability as their core business functions become increasingly dependent upon network services. Well-established business services based on Frame Relay, ATM, and TDM private lines that have traditionally been a lucrative offering for providers are at risk of being displaced by newer and more efficient packet-based transport technologies based on IP and MPLS.

Small and medium sized businesses may use DSL access as an alternative to more costly leased-line, Frame Relay, or ATM WAN services for inter-site connectivity. Other business DSL users may be remote workers of a large corporation that need permanent Virtual Private Network (VPN) access from their homes. For these types of customers, this provider offers IP-VPN service that provides secure and reliable data transport for a closed user community. The SmartEdge MSER enables this service to be offered as another integrated function with the need for additional hardware.

For business VPN customers, L2TP traffic is transported across the backbone network and terminated on the SmartEdge MSER in the appropriate VPN instance. Larger customers requiring higher bandwidth or alternative connectivity may attach to a VPN with a dedicated Ethernet link ATM connection, or any of the other interface types available on the SmartEdge MSER.

Virtual context technology enables the SmartEdge MSER to create thousands of logically separate domains within a single platform, each functioning as an independent virtual router. VPN traffic is isolated in this manner with each virtual router having its own route tables, IP address space, and routing protocol instances. Traditional issues regarding overlapping IP address space or routing instability caused by one customer impacting another customer are eliminated with this functionality. Each customer can also monitor and manage their individual virtual router instance as if it were a private physical router.

Benefits
As one of the primary carriers in the US, this company’s network services are highly visible throughout the industry as they reach a substantial customer base. Service downtime is unacceptable and may have severe business impacts. With a telecom heritage of five nine’s availability, this operator demands the highest levels of reliability in their overall infrastructure. The SmartEdge MSER was able to meet these stringent requirements with fully redundant hardware architecture and in-service software upgrade capabilities.

The SmartEdge platform enabled this customer to effectively scale their residential and business services across the region while simplifying overall network architecture and operations. For VPN services, the SmartEdge MSER provided unique service creation capabilities for broadband business users such as L2TP and PPP termination into IP-VPN virtual routers. This was possible on the same platform that provided residential broadband services, enabling optimal network design by reducing the number of required network elements.

As this provider introduces IPTV and enables triple-play services, the advanced QoS capabilities of the SmartEdge MSER will ensure that real-time voice and video traffic receive the appropriate priorities to minimize latency and jitter. Furthermore, features such as hierarchical QoS make a tiered service model possible while session-level visibility allows for metering of individual user applications. All of these resources are available for this provider in the same platform without a need for any additional hardware or software upgrades.