SDN / NFV Overview
Network Operator Challenges
Network traffic is growing rapidly, as indicated by a 13-fold increase in global mobile data traffic forecasted over a seven year period*. This is creating a critical business challenge for network operators: how to best address this traffic growth by building out infrastructure in a way that does not outpace the revenue generated by the services deployed on the infrastructure. This can be accomplished by improving bandwidth management, spending less on equipment, and deploying new profitable services more quickly – all facilitated by SDN architecture.
SDN makes it easier to manage bandwidth by giving operators the ability to manage network assets from a central control point with a global view instead of a decentralized, local view. This is because SDN architecture separates control and data plane functions within a network device, allowing traffic to be controlled with greater automation, more intelligence, and less support effort. Moreover, network functions run on industry-standard servers that typically have lower capital and operating expenses (CapEx/OpEx) than purpose-built network elements. Complexity is also reduced when network functions run on a common hardware platform, making it easier and faster to launch new services.
Another challenge facing network operators is insufficient knowledge about the traffic on their networks, much of which is third-party applications and services. Consequently, it is more difficult to enforce policy, manage traffic and differentiate services, among other things. Today, SDN implementations are limited to L2-L4 headers, and as a result, switches cannot differentiate traffic from various L7 applications. This leads to the inefficient use of both network bandwidth and compute resources since each specialized system, like media servers, has to analyze all the traffic in order to pick out just the relevant flows (e.g., streaming video) and then process them.
* Source: “Cisco Visual Networking Index: Global Mobile Data Traffic Forecast Update, 2012-2017,” February 6, 2013.
The Solution: Embedded L4-7 intelligence
L4-L7 DPI fills this gap by providing the network application and metadata information required for more intelligent decision-making. Expansion of DPI visibility in the OpenFlow protocol allows a switch to redirect application flows to specialized services of value to operators or end users. This is the basis for a service-aware network architecture designed to provide operators more control over their networks through improved policy control, video optimization, load balancing, firewalling, network monitoring, and more.