 | Issue: | Asia-Pacific III 2008 |
| Article no.: | 14 | |
| Topic: | Bandwidth management for IP networks | |
| Author: | Kurt Dobbins | |
| Title: | Chief Technology Officer, IP Services | |
| Organisation: | Arbor Networks | |
| PDF size: | 243KB |
About author
Kurt Dobbins is the Chief Technology Officer, IP Services, of Arbor Networks. Mr Dobbins has over twenty years of engineering and product development experience, and has led pioneering efforts in switching, service networking, routing, network management, and communication systems. He was the founder of Ellacoya Networks. Prior to Ellacoya, Mr Dobbins was Technical Director for Cabletron Systems, where he engineered and shaped product development for advanced switching solutions. Mr Dobbins is the named author of over a dozen patents in networking and communications, with six additional patents pending.
Article abstract
The rise of bandwidth-intensive applications such as video and peer-to-peer file sharing is overwhelming ISPs trying to provide good service at razor-thin margins. To roll out the new services subscribers want, they need the flexibility to manage network traffic to optimize performance and minimize costs. Traditional all-you-can eat pricing models encourage unbridled consumption by a small percentage of users. By using deep packet inspection to prioritise traffic, not to censor applications, ISPs can align their service pricing with subscribers’ actual usage.
Full Article
The explosion in the volume and diversity of traffic running over today’s 21st century IP-based networks is creating serious challenges for service providers who are trying to provide a good service to every subscriber at prices with razor-thin margins. Its economics It is a challenging new world for today’s service provider. Many providers are burdened with high debt, slow revenue growth in traditional lines of business, and single-digit or negative margins. To roll out the new revenue-generating services subscribers are clearly hungry for, they need the flexibility to manage network traffic to optimize performance and minimize costs – for themselves and their customers. Fair treatment With the rise of bandwidth-intensive applications such as video and peer-to-peer file sharing, bandwidth demands have gone through the roof. At the same time, traditional all-you-can-eat pricing models encourage unbridled consumption by a small percentage of users. On fixed and mobile broadband networks, an estimated ten per cent of subscribers consume 80 per cent of the bandwidth. Further, during peak hours that ten per cent compromises network performance for the 90 per cent. This is a fairness issue providers can address by managing and prioritizing traffic – not to censor particular applications, but to realign service pricing with subscribers’ actual usage. Network intelligence and service control Deep packet inspection (DPI) is a critical network technology; it provides information on how the network is being used, when it is used and, optionally, by which applications and subscribers. DPI provides the tools necessary to manage the network to ensure fairness across the full spectrum of users, from heavy users who enjoy gaming, movie and video downloads, to light users who occasionally surf the Web and check emails. When providers deploy DPI in the network, they typically begin with monitoring and reporting, which shows where network capacity is over – and under – utilized. This gives them immediate insight into where they can target cost reductions through more efficient bandwidth utilization. They quickly move to next phase, which is to intelligently manage traffic to ensure quality of service and fairness, and to optimize the use of existing capacity. On a tactical level, this information supports decisions about capacity planning, investments in access networks and peering networks, and how to improve service quality, especially during peak hours when the network may be congested. For example, during peak hours they will prioritize real-time applications, such as voice and video, by time-shifting peer-to-peer file sharing into off-peak hours. On a strategic level, the ability to understand and manage traffic for every application and every subscriber allows providers to transform their business models and their service brands. Service providers are using DPI to deliver differentiated services and offer a range of service plans for targeted subscriber demographics. For example, heavy users of gaming or peer-to-peer services could opt for a premium service that ensures high-priority, has low-latency and does not time-shift file sharing. This requires DPI solutions that are integrated with provisioning and other back office systems. Tiered services and transparency UK broadband provider PlusNet offers an array of residential broadband services, called ‘Broadband Your Way’, ranging from an entry-level service for light users to high-end broadband for heavy gamers, VoIP and peer-to-peer (P2P) file sharing. PlusNet also has a specific plan for gaming that offers quality broadband with low ping and latency, called ‘Broadband Your Way PRO’. According to Alistair Wyse, Chief Technology Officer at PlusNet, “PlusNet strongly believes that delivering service plans that fit the needs of individual subscribers is the best way to ensure a rewarding customer experience.” Wyse went on to comment on how much the Internet has changed in recent years. “A large number of customers are still using it predominantly for Web and email, while a fast-growing segment of others are using bandwidth intensive applications such as P2P and video. We do not think that a one-cost-for-access model can work in this changing environment, so we set out to develop tiered services that meet the needs for the different types of Internet users. By fully disclosing what we are doing and why, the result has been increased customer satisfaction and reduced churn. It’s a win-win for us as a provider, and our customers.” PlusNet clearly explains each of the service options and why the network needs to be managed during peak busy hours in order to ensure fairness and to deliver a high quality real-time and interactive experience. Each plan is designed to appeal to a different demographic, from a light user that does not use file sharing to a heavy user that wants full-time file sharing and streaming availability. Rather than have a one-plan-fits-all service, PlusNet offers consumers plans that fit their specific service and economic requirements. Without DPI for traffic management, PlusNet could only guarantee service by over provisioning bandwidth. Instead, PlusNet fully discloses maximum downstream and upstream bandwidth rates for specific application types, such as peer-to-peer file sharing, as well as which applications are prioritized, for each service option. The ISP cost model drives the need for some form of traffic management, so PlusNet also discloses how UK ISPs pay for bandwidth. With this information, customers can understand the business reasons for employing traffic management techniques during peak hours and, as well, as the future plans for the network based upon capacity planning and traffic management. PlusNet employs three methods of ensuring fairness on their network during peak busy hours: 1) Traffic management – For certain plans, maximum bandwidth rates for peer-to-peer file sharing and other file downloading services are managed during peak busy hours. Each service plan comes with a higher or lower degree of traffic management. 2) Prioritization – For all plans, interactive applications like Web and real-time applications such as VoIP have higher priority than non-real-time or ‘background’ applications. 3) Changing human behaviour – For all usage-based plans with a monthly usage allowance, subscribers have an economic incentive to use the network during non-busy off-peak hours. All off-peak-hour usage is free and does not count against the monthly allowance. PlusNet publishes network traffic graphs depicting how the network is used during peak and off-peak hours, clearly demonstrating the benefits of their traffic management policies. By prioritizing interactive applications like the Web and streaming, PlusNet ensures a great customer experience during peak busy hours between 8pm and 10pm. Conversely, by managing peer-to-peer file sharing during peak hours, and encouraging consumers to share files at night for free. PlusNet is able to get better utilization of its network bandwidth. Shifting file sharing to off-peak hours when there is unused bandwidth capacity has a dramatic effect; it lets PlusNet keep its costs down by deferring expensive bandwidth capacity upgrades. By being transparent about service offerings and bandwidth management practices, PlusNet has improved customer satisfaction and won industry recognition. DPI technology gives wire line and wireless broadband operators unprecedented visibility into – and control over – their networks and services. DPI measures traffic by application, activity and subscriber, and then gives providers the tools to analyze the resulting data through a Web-based reporting environment. Providers can then maximize network efficiency by setting policies that prioritize applications during peak and non-peak times, secure the network, and control bandwidth costs. The technology also provides a platform for introducing targeted service plans and packages for new offerings such as VoIP, online gaming and movie downloads, that give providers new revenue opportunities. It is a win-win situation when providers get the control they need to manage their networks and offer new services, while consumers get customized service plans that fit their diverse usage and economic needs.
