“A communications network forms the backbone of any successful organization. These networks transport a multitude of applications and data, including high-quality video and delay-sensitive data such as real-time voice. The bandwidth-intensive applications stretch network capabilities and resources, but also complement, add value, and enhance every business process. Networks must provide secure, predictable, measurable, and sometimes guaranteed services. Achieving the required Quality of Service (QoS) by managing the delay, delay variation (jitter), bandwidth, and packet loss parameters on a network becomes the secret to a successful end-to-end business solution.”
Cisco
In modern packet-switched networks, QoS (Quality of Service) is the set of techniques that attempt to ensure delivery of the most critical applications on the network. For example, voice and video content is time-critical (ie delay sensitive) and needs prioritised delivery so it is generally more important to guarantee this type of traffic. Alternatively, file transfers are less delay sensitive, but are definitely loss-sensitive (ie sensitive to dropped packets).
QoS becomes increasingly important as larger amounts of voice and video converges onto the world’s data networks. Closely linked is the concept of Policy Based Charging (PBC), whereby CSPs can offer customers increased prioritisation at premium rates.
QoS and PBC are just two examples of distributed decision making around the network. As processing power increases and virtualisation becomes more prevalent, distributed processing opportunities will continue to present themselves. Current OSS primarily operate on a centralised processing model and struggle to handle the sheer volume of real-time transactions occurring in the network, so they also don’t always have the impact that they could.
SDN has the potential to provide the distributed computing grunt that could allow the OSS to be distributed and hence have a more real-time impact on future networks rather than being not-quite-real-time (or in some cases not-even-close-to-real-time).