Correlation faults between softswitch and bearer network means that the fault phenomenon is reflected on the switch side, but the actual fault point is the network fault on the IP bearer network. There have been many related failures in the operation of the softswitch network. The failure has a large impact and is difficult to deal with, which has become a common problem faced by relevant maintenance departments. Relevance problem analysis At present, the soft-switching network and the IP bearer network are still loosely coupled. This loose coupling is embodied in two aspects: firstly, it is reflected in maintenance management, which is often divided into professional maintenance management by different teams, and is monitored by different network management systems, and IP network maintenance often only considers the characteristics of the original Internet and private line data services, and does not consider the characteristics of real-time services such as voice. Its end-to-end service quality change of the bearer network lacks corresponding means; secondly, it is reflected in technology At the service layer, the softswitch network lacks an effective means of sensing the end-to-end service quality of the bearer network. When the bearer network fails or the service quality deteriorates, the softswitch cannot accurately and timely alert and switch. Due to this loose coupling relationship, there is a lack of detailed and accurate alarm information on the device and the network management, and the main fault handling personnel are generally still exchange professionals, causing the operation and maintenance personnel to do not know how to deal with the fault, which seriously affects the efficiency of fault repair. At the same time, compared with the original PSTN network, the softswitch network uses the IP network as its bearer network, which also reflects different characteristics in the relationship between bearer and service failure, as follows. ——Switching protection in the switching side: In the PSTN network, the switch can sense TDM transmission problems (such as interruption and sliding code) and switch, while the IP network can only sense the interruption of the physical layer of the bearer network, but not the QoS changes of the bearer network. Therefore, the softswitch network cannot switch according to the QoS of the bearer network. ——The protection switching capability of the bearer network: The transmission equipment in the PSTN network can perform protection switching based on interruption and sliding code, and the protection switching capability is strong, while the IP network can only switch according to the physical layer interruption, and cannot switch according to QoS changes, resulting in The non-interrupted failure of the IP network board easily affects the softswitch service. ——Fault location means: The transmission protocol in the TDM network is relatively simple (mainly the physical layer), and it can be quickly located by simple maintenance methods such as self-loop, while the application layer and other protocols are involved in the IP network. The problem is more difficult, which makes it difficult to quickly distinguish between a softswitch and an IP bearer in a softswitch network. ——Voice quality: The PSTN network has exclusive bandwidth when it occupies the voice path, and all users in the IP network share the bandwidth, making it difficult for the IP-based softswitch network to guarantee reliable voice bandwidth. ——The granularity of voice transmission: 2M and 155M interfaces are used to transmit services in the PSTN network, and the granularity is relatively small, while the IP-based softswitch network traffic is concentrated, and the core equipment is mostly transmitted through the GE port, and the business granularity is large , Making the impact of the bearer network failure on the business volume huge. ——In terms of network maintenance indicators: The definition of a major fault in the PSTN network that affects 100,000 user hours is a major network fault, and the highest service standard for IP networks (gold customers) is 4 hours of fault repair time, which makes the bearer network consider smaller faults. The soft switching network will become a major failure in terms of providing voice services. Due to these differences, compared with the original transmission network failure on the switching network, the IP bearer network failure has a greater impact on the soft switching network, and we can not borrow some of the original PSTN troubleshooting methods and experience to deal with soft switching and The associated fault of the bearer network. This requires the maintenance department to focus on softswitch bearer characteristics and to innovate from the maintenance operation system and maintenance methods. On the one hand, the probability of softswitch and bearer-related failures is minimized, and on the other hand, the efficiency of handling softswitch and bearer-related failures is improved. Suggested countermeasures The reasons related to the softswitch and bearer correlation problems are more complicated, and many technical problems and support methods cannot be solved in the short term. Therefore, it is recommended that the relevant maintenance departments take different countermeasures at different stages and according to different conditions. (1) Short-term response measures The purpose of short-term countermeasures is to reduce the probability of occurrence of softswitch bearer failures, shorten the time for handling faults after the occurrence of bearer layer failures, and avoid the expansion of the scope and impact of failures. ——Carry out network self-inspection to reduce hidden troubles; ——Optimize the alarm information of softswitch equipment and network management; ——Enhance the transparency of the bearer network; ——Incorporate the softswitch CE equipment into the data maintenance department for unified maintenance; ——Combine the softswitch and bearer network protection switching methods to ensure the coordination of protection switching; ——Summary the fault phenomena, optimize the fault handling process, and suggest that the relevant departments handle them in parallel under partial fault conditions. (2) Interim response measures The purpose of the mid-term countermeasures is to enable automatic detection and real-time alarm of the monitoring system for the quality and faults of the bearer network, and maintenance personnel to take the initiative to deal with the business before the large-scale users are affected. The main methods include the establishment of a full-range quality monitoring system at the bearer layer and a softswitch integrated alarm system. ——Establish the whole-process quality monitoring system of the bearer layer Aiming at the problem that the existing bearer network lacks end-to-end service quality monitoring means, it is recommended to build a whole-process quality monitoring system of the bearer layer by deploying probes to end-to-end the softswitch bearer network Real-time monitoring of connectivity and service quality. ——Establish a comprehensive softswitch alarm system. At present, the softswitch and bearer networks of the current network manage the equipment through their own network management systems. System alarms are only output to their own network management. In the event of a problem, maintenance personnel need to comprehensively check multiple systems for failures. Correlation analysis and judgment affects the speed of troubleshooting. In response to this problem, it is recommended to build a comprehensive softswitch alarm system to centrally present the alarms of softswitch equipment and bearer network equipment, as well as signaling monitoring, bearer monitoring and other auxiliary systems, and to associate the softswitch and bearer network faults and occur in the network In case of problems, the fault point can be quickly presented, and the maintenance personnel can be guided to deal with it in time. (3) Long-term response measures The purpose of the long-term response measures is to automatically discover, real-time alarm, and automatic switching for the network fault bearing layer equipment to minimize the impact surface. The main measures are: ——On the basis of the whole-process quality monitoring system of the softswitch service, the device switching control function is added to enable it to control the switching of the softswitch system and the bearer network equipment through the detection results. ——Requires bearer network equipment manufacturers to improve the equipment according to the characteristics of the real-time services carried (such as voice, fax, video, IPTV, etc.), provide traffic monitoring, flow control, network index monitoring, alarm notification, automatic routing switching, etc. Features. The bearer mode of the packet network increases the difficulty of maintaining the softswitch network, but we cannot deny the application results of the softswitch network due to these maintenance difficulties. At present, the maintenance department can reduce the occurrence of faults through the improvement of fault handling methods and the accumulation of maintenance experience. Probability, improve the efficiency of fault handling. But in the end, to solve the impact of the bearer network failure on the softswitch service, it is also necessary to continuously improve the softswitch system so that it can sense the bearer network failure and the change of service quality, so that it can quickly switch when the bearer network failure occurs, reducing the business influences. Easy Electronic Technology Co.,Ltd , https://www.pcelectronicgroup.com
A big difference between the softswitch network and the traditional PSTN is the switch from circuit switching to packet switching, and its bearer network from the transmission network to the IP packet network. While this transformation brings various advantages to operators on the network and services, it also poses some new challenges to maintenance. Among them, the handling of the correlation failure between the softswitch and the bearer network is a major problem that plagues the maintenance of the softswitch network. In recent years, Chinese telecommunications operators have begun to build large-scale softswitch networks.