Introduction
Before the arrival of MPLS and the advance in silicon technology for ASIC and network processors in early 2000s, many carriers ran multiple single-purpose networks such as TDM, ATM and IP to support their video, voice and data network services. Some enterprises attempted to consolidate their triple-play traffic onto a single IP network. However, due to the silicon technology and QoS implementation on IP routers at that time, they were required to over-engineered their IP networks to support peak traffic usage. In other words, they avoided network traffic Quality of Service (QoS) issues by preventing the switches and the network links from being congested at the first place. The IP network became a Multi-Input Multi-Output First-in First-Out network that was underutilized most of the time until peak network usage happened.
In early 2000s, with the advance in silicon technology and networking standards such as MPLS, network vendors could develop network switching platform such as MPLS that could support triple-play traffic with the desired QoS. In other words, the MPLS network can be over-subscribed to take advantage of the burstiness nature of packetized triple-play traffic and when peak network usage happens, QoS constructs provisioned in the network switches can kick in to ensure high priority traffic such as voice can be…
