Chengdu Telecom Man Qos Deployment

The Internet provides best effort interconnection service, which is lack of reliability, so that it is only met for connectivity applications. While multimedia technology develops rapidly, the Internet has gradually evolved from a pure data network into a integrated transmission network that can transmit data, voice, image, and other multimedia information, so as to serve IP phones, real-time video conferencing, video streaming, distance learning, secure business trade, inter- enterprise business, as well as other low-bandwidth but conversation sensitive applications. Clearly the way of best effort is unable to satisfy these applications, which require Quality of Service (QoS). The network should be redesigned based on these applications in order to control the bandwidth occupied by low-end business network, and guarantee the Quality of Service for high-value-added applications. To a Network Service Provider, one of the aims is to increase the profitability as possible within limited resources and network bandwidth. QoS allows service providers to serve the type of priority, bandwidth allocation, in order to control the network bandwidth, delay, jitter and packet-loss. By deploying QoS features according to the Service Level Agreement (SLA), service providers can treat flows designated by SLA in preference to other flows, thus ensure the implementation of the network strategy and guarantee the specific application data stream transmission.Internet Engineering Task Force (IETF) defines two models for the implementation of QoS: Integrated Services (Int-Serv) and Differentiated Services (Diff-Serv); Int-Serv complies with QoS signaling model, and terminal hosts send signaling to the network to request QoS, so as to set aside bandwidth and network resources; Diff-Serv works on the QoS configuration model, and the service units are set to varied types of data streams with different QoS requirements; Int-Serv or Diff-Serv model can be applied according to the strategy.The Metropolitan Area Network of Chengdu Telecommunication Corporation mainly provides the non-difference service or ordinary broadband service and lease line service. As value-added services growing rapidly, this network can not acclimatizes itself to the development of business. In order to turn this Metropolitan Area Network into a integrated business carrier network that has the ability to provide comprehensive service support, satisfies the requirements of different customers, with excellent extension and stability, in which all business and devices can be managed and analyzed, according to the claims of China Telecommunication Corporation and Sichuan Telecommunication Company Limited, Chengdu Telecommunication Corporation carried out the test and evaluation of all devices'ability to support QoS within the Metropolitan Area Network of Chengdu Telecommunication Corporation and finally fulfilled the deployment of QoS throughout the entire Metropolitan Area Network. Devices at the pool layer classify and tag customers'flow, also regulate and reshape that flow. Devices at the core layer provide a scheduling mechanism for a strict priority queue and many poll queues, schedule and transfer data packet based on its QoS level, following a discarding mechanism. By this way, a customer's Quality of Service can be guaranteed when there is jam on the link.Having been deployed QoS, the Metropolitan Area Network of Chengdu Telecommunication Corporation becomes a clearly structured, completely functioned, centrally controlled integrated business carrier network with the ability to provide differentiated services, that can afford voice, video and data services. Many technical support and experience have been acquired for the succeeding province-wide deployment of QoS.