Case Study - Redback Simplifies Delivery of IPTV, Business VPN, and Internet Services for Chunghwa Telecom

Situation
The Golden Belt Telephone Association (GBTA) is a Kansas telephone cooperative that provides local and long distance telephone service to the golden belt region of Kansas. In addition to traditional PSTN service, they also provide high speed Internet (HSI), mobile and cable television service. All the services except for cable television were fairly ubiquitous throughout GBTA’s service area. Since many of the areas were sparsely populated, the plant build out for cable television was cost prohibitive. As a result, the residents that lived in the rural areas resorted to satellite television.

These residents were unable to receive the local broadcasts that provided alerts to customers during the annual storm season. With the advancements in IPTV technology, GBTA realized that they could provide the residents of the rural areas cable television service that was comparable to that available in the more populated areas.

To deliver IPTV services, GBTA needed to build out a network that could carry all the services it provided. Due to the large geographical area and the low population density, building out separate networks for each service was not an option. In addition, the network needed to be highly resilient to failures since GBTA’s services were absolutely critical for its customers and maintenance was difficult since the central offices were geographically disperse.

GBTA also planned to assist with the Kan-ed program, whose purpose is to expand the collaboration capabilities of Kansas’ education institutions, libraries, and hospitals. This program encourages video collaboration and innovative distance learning initiatives for certification and ongoing training for professionals living in rural areas. Since the network was to serve public and private constituencies, the resiliency, availability, and performance was critical for GBTA.

Solution
To build out a next generation network that was highly reliable and capable of providing all of the services offered, GBTA selected the SmartEdge Multi-Service edge Router. The combination of edge routing, Ethernet aggregation and subscriber management provided a platform that could be used to provide IPTV, HSI for WiFI and DSL access.

GBTA took advantage of the SmartEdge platform’s virtual router capability to create three separate, logical networks on a common network infrastructure. This capability allows for the creation of logically separate and distinct virtual routers. Each virtual router has all of the functionality that is available from an actual physical router. It has its own route tables, IP address space, and routing protocol process.

Video and High Speed Interne Networkt
With a SONET transport infrastructure in place, the SmartEdge Multi-Service edge Router were deployed at the edge to add service intelligence to the network. Internet group management protocol (IGMP) was used to communicate channel changes. Protocol independent multicast sparse mode (PIM-SM) was used to minimize the amount of bandwidth consumed by the broadcast television service. The SmartEdge Multi-Service edge Router received the broadcast television stream through network facing Gigabit Ethernet links and replicated the broadcast television stream for each individual subscriber and mapped it onto a bridged PVC for delivery over DSL.

The HSI traffic was transported on a PPP encapsulated PVC to the Internet. The SmartEdge Multi-Service edge Router controlled the bandwidth consumed by the HSI to ensure that it did not interfere with the broadcast television stream. The QoS was applied on a per subscriber basis to ensure that no single subscriber consumed an inordinate amount of bandwidth.

The SmartEdge Multi-Service edge Router also aggregated WiFi subscribers. This traffic was aggregated through a 10/100 Fast Ethernet link and transported to the Internet using PPP encapsulation.

The diversity of interfaces and edge routing capabilities allowed GBTA to deploy a single creation platform for all of its IP services. This simplified the design, deployment, and ongoing maintenance of the network.

Management Network
A separate, logical management network was created using the SmartEdge Multi-Service edge Router virtual router capabilities. GBTA took this approach since a majority of their POPs were actually huts in rural areas. As a result, no physical connectivity was available for an out of band management network. By using a dedicated virtual router, OSPF, and common VLAN, GBTA was able to create a logical out of band management network. This approach had all the benefits of having a dedicated out of band management network without the need to create a physically separate network.

For alarm monitoring and maintenance, GBTA deployed the NetOp EMS. With its tight integration with the SmartEdge Multi-Service edge Router and standards based application programming interfaces, it facilitated the back end integration with billing and operational support systems.

High Availability
The SmartEdge Multi-Service edge Router has the ability to seamlessly failover and maintains all subscriber and multicast sessions in the event of a failure. This capability provides continuous services, which is critical to the residents of rural Kansas. Unlike other data networking platforms, the SmartEdge Multi-Service edge Router continues to forward traffic even when a control module fails.

Benefits
The SmartEdge platform enabled GBTA to deploy a network that is efficient in design and performance. Furthermore, the network is extremely reliable and provides the scalability to add additional services and subscribers in the future. The carrier class reliability that comes from a purpose built platform essentially allows GBTA to provide a broadband dial tone to its customer base.

The single, next generation IP network infrastructure provides GBTA advantages operationally. Rather than having to build out and manage separate networks for each service, they now only need to manage a single common network infrastructure. As services advance and their customers demand features such as mobility, they will be able to provide a common experience regardless of access technology or end device. GBTA has already begun to go in this direction by offering WiFi and DSL access services.

Another benefit is the time to market for new services. Since there is a consistent central service creation point at the IP edge, creating new services is easier than if multiple service creation points were deployed. For example, one possible future service is VoIP, which requires advanced QoS due to the sensitivity of the traffic to jitter and latency. Once the traffic QoS management requirements are established in the SmartEdge platform, the QoS policies will be applied whether the access is through DSL or WiFi.

There is no doubt that as broadband adoption continues to grow, the end customers will become more advanced and demand more bandwidth and services. With its converged, next generation network, GBTA is in an excellent position to provide its customers world class broadband and IP services.