Intelligent IP Traffic Management for Cable Service Providers

Dyband allows Cable Internet Service Providers to deliver consistent, reliable access services by controlling the bandwidth consumption of individuals and groups, defining and managing service level agreements and providing "visibility" tools for service management. Dyband enables ISPs to increase revenue, decrease operating cost, improve service margins and decrease churn.

The Challenges: What's coming down the pipe?

It is estimated that bandwidth demands on a broad market level for digital television, e-mail, video-conferencing, cable television, and local and long distance voice service will more than double to about 4.5 million Tbits/sec in 2003 from about 2 million Tbits/sec in 2000. Cable Internet Service Providers in particular are attracting increasing numbers of users with the promise of high bandwidth and exciting new multimedia content.

As a result, Cable networks will be faced with not only more traffic, but also a different type of traffic as users shift from mostly Web surfing to downloading trial software and music, or participating in bandwidth-hogging, latency- and jitter-sensitive activities such as VoIP, video gaming, video streaming, live entertainment, business and educational events.

Managing this increased demand while increasing your customer base will become a monumental challenge. Left unmanaged this demand will result in erratic network performance, slower-than-promised transfer rates, and service degradation.

The Dyband Solution

Dyband, an intelligent IP traffic management solution, measures and controls the bandwidth usage of individuals and groups, allowing service providers to control aggressive users, minimize network congestion, reduce packet loss, and eliminate congestion-related outages. By efficiently managing existing bandwidth, service providers can add more subscribers to the current Internet backbone connection, minimizing network costs and increasing service margins.

Easily configured, Dyband allows ISPs to define and manage a wide range of service levels at distinct price points, allowing them to gain incremental revenue without purchasing additional bandwidth. Dyband allows ISPs to monitor access services in real-time while gathering historical data for analysis to improve service management.

An extensive collection of historical statistics is provided to facilitate the performance of the entire managed network, enabling network administrators to make informed analysis to improve service costs and management.

Figure 1. A Cable network with Dyband installed. Shaper is easily configured through the CMon application to manage bandwidth usage and collect real-time statistics.

Network Architecture

The network diagram in Figure 1 depicts Dyband deployed in a Cable network. The Shaper is installed between the distribution network and Internet router. It is responsible for shaping all subscriber Internet traffic and collecting all real-time statistics.

Since the Shaper has no user interface, a separate application-CMon-is used to configure and manage the Shaper. With CMon, the network administrator can view and modify the topology of managed objects, manage the profiles of service levels and view real-time statistics. ProfilePush distributes global profiles to remote Shapers. Archiver extracts real-time statistics from one or more Shapers and stores them in an ODBC database. The Miner application allows network administrators to generate and view reports that contain historical performance data.

Dyband runs on industry-standard hardware platforms and allows essential operational status information to be monitored by existing network management platforms via SNMP.

IP Traffic Management

Dyband shapes traffic for up to 50,000 managed objects. These can represent individual subscribers or aggregate traffic associated with physical network devices or logical entities. Inbound and outbound traffic is managed separately at each network point in order to support asymmetric networks and provide the finest granularity of bandwidth control. Dyband evaluates the state of the network 100 times a second. Bandwidth is allocated according to predetermined service levels during normal traffic patterns and automatically reduced across all subscribers, equitably, during periods of congestion.

Dynamic priority mechanisms give higher priority subscribers preferred transfer rates, while ensuring that lower-priority subscribers are not completely "starved" of bandwidth. If desired, the system can be configured to adjust individual transfer rates based on usage. Real-time traffic shaping capabilities minimize periods of congestion and quickly return the network to normal shaping operation. Dyband dramatically reduces packet loss and eliminates congestion-related outages.

Service Levels and Management

Dyband enables a virtually unlimited number of service levels that can be structured based on transfer rates and access priorities. Profiles are used to define these service levels, and wizards are provided to assist administrators with the initial definition. Once created, profiles can be assigned manually by name to new network points or automatically to newly discovered subscribers.

Performance Visibility

Dyband maintains a moving 24-hour window of statistics for each managed object. Reports on "Top 10" users, based on operator defined criteria, provide real-time visibility into who is consuming bandwidth. In addition to displaying these statistics in real-time, Dyband can store the statistics in any ODBC database for later reporting and analysis. This facilitates capacity planning, well-timed provisioning, usage-based billing, and customer and technical services.

Autodiscovery and Configuration

Dyband uses an intuitive tree-oriented display to represent all managed objects. The system automatically discovers new subscribers, as they become active on the network and places them appropriately in the topology tree. The system resolves the names of newly discovered subscribers using DNS, LDAP, or RADIUS, and immediately begins shaping their traffic based on inherited SLA profiles.

Fault Tolerance

Automatically transfers to "hot" standby system upon hardware/software failure, with continuation of traffic shaping and statistical recording. By doing this it protects against a single point of failure in the network and guarantees continuity of traffic shaping and statistical recording.