Look at the practical application of soft switch technology in NGN

The soft switch technology is still quite common, So I studied the practical application of the soft switch technology in NGN. I will share it with you here, hoping it will be useful to you. Soft switches are important devices and systems that provide call control in various services of the Next Generation Network. However, soft switches are not all about the next generation network. As an important part of next-generation network call control, soft switches still need to work with other key technologies and equipment to jointly develop richer video and multimedia services.

1. Thoughts on popular soft switch ideas

At present, one popular term in the discussion of soft switches is "Softswitch is the core of the Next Generation Network". I think this term is worth further consideration and discussion. The soft switch technology is one of the most important and critical technologies in the Next Generation Network for voice business aggregation nodes. There is no doubt that we should give extraordinary attention and attention. However, the technical features of vswitches do not provide the only direct core network technology.

In addition, the concept that "Softswitch is the core of the Next Generation Network" will bring about confusion in some basic propositions and logical confusions. The core technologies of the Next Generation Network should fundamentally include various network technology systems that support voice, data, and video services. The soft switch itself is only a local device system and does not have the characteristics of a comprehensive network architecture. Vswitches do not directly provide IP data services. Vswitches support video and multimedia endpoint services through the extension of call control mode and functions. However, vswitches still need to collaborate with other key technologies and devices to develop richer video and multimedia services. The soft switch technology is mainly designed for centralized call control functions. In addition to the soft switch technology, the next generation network will also rely on a series of other existing IP technologies and other application technologies to support voice, data, video, and other services.

In terms of policy, the phrase "Softswitch is the core of the Next Generation Network" often easily leads to the assumption that the soft switch technology is equivalent to the next generation network technology, so as to focus on the research and practice of a single soft switch technology and its surrounding areas. The future investment will only be considered for devices and systems related to vswitches. This leads to short-sighted strategic thinking that only looks at trees and does not look at forests.

In terms of technology, "Softswitch is the core of next-generation networks" often easily leads to the expectation of all next-generation networks on soft switch devices, then, we thought about constructing the so-called next-generation network with soft switches as the core, so that the discussion and practices on next-generation networks remain at the conceptual level of basic, local, small-scale, and individual device system technologies for a long time, as a result, the local structure of the soft switch is the overall network architecture of the Next Generation Network.

In practice, the test and Discussion on the networking mode of soft switches are very easy to cause people to ignore the practice and discussion of other next-generation network technologies, thus limiting that the next-generation network can only be connected by soft switches. the "no-network" mode of the full flat network ". Obviously, the "no-network" next-generation network architecture can only support one or several soft switches, which is not suitable for telecom operators to operate on a large scale. This phenomenon is called the "island phenomenon" of the soft switch technology practice ".

In terms of the network structure, "Softswitch is the core of next-generation networks" cannot answer questions such as the need for next-generation networks without core network technologies. If not, how can we avoid the "island phenomenon" of soft switches ", if necessary, what is the core network technology of the Next Generation Network, how to solve the coordination and interconnection between soft switches, how to carry out the next generation network-wide business and other basic issues.

2. Analysis of Two policies for the NGN network architecture system

In the discussion of the next-generation network architecture system, there have always been two different strategies: one is to emphasize smart endpoints, edges, and simple network facilities, because the driving force of end-to-end multimedia convergence comes from endpoints and edges, the flourishing innovation and prosperity of next-generation network services depend on this. The success of the Internet also confirms the importance of this idea to multimedia services. Another idea is to advocate simple endpoints and edges and smart network facilities, because only simple and unified endpoints and edge devices are conducive to standardized management and control. The speech service provided by the PSTN network has verified the reliability of this business practice. Itu h. The 323 protocol and the ietf sip Protocol are the technical systems that reflect the first strategic thinking to some extent. MGCP/H of IETF/ITU. Vswitches characterized by the 248 protocol are the means to implement the second strategy. As mentioned above, in order to achieve the telecom operation goal of end-to-end IP phones to a greater extent, people have designed a soft switch technology mechanism for telecom operators. The IP telephone voice service is the most important and fundamental service function in the soft switch.

Obviously, the true meaning of the next generation network requires both the innovation and prosperity of smart endpoint services and the system's scalable management. The difficulties discussed in the next-generation network architecture system are how to comprehensively balance multiple technologies. I think that, considering the current technological maturity and development, H. 323 protocol, SIP protocol and MGCP/H. Vswitches characterized by the 248 protocol are implemented by IP phones and next-generation networks. These three technologies have their own differences and expertise that need to complement each other. The best strategy is to adopt a network architecture system and implementation means that integrate the three technologies.

In fact, the system of the Next Generation Network should be composed of the core network and the local soft switches located in the next generation network access and edge locations. The core network of the Next Generation Network is a backbone communication network that covers the service scope of operators. It is used to achieve interconnection between soft switches, between multiple operators, and between different networks, implement network-wide traffic control and scheduling, share the network-wide services of centralized database retrieval, share the business creation environment, and provide network governance across the network. The core network of NGN provides functions such as networking, routing policies, traffic control, network-wide service creation and governance, and network-wide maintenance and governance. It is obvious that among the three main technologies implemented by the next generation network IP Phone, H. 323 protocol network technology and SIP network technology will play a major role in the core network. Many telecom operators in the world have used H. 323 of the proxy servers for network guard or SIP and other network application servers achieve networking, networking, and network-wide business and O & M.

This does not mean denying the important and vital position of the soft switch technology in the Next Generation Network. The next-generation network architecture is developed by H. 323 and the SIP network system, but the access and convergence of the most popular and basic IP phone services in the next generation network mainly rely on MGCP/H. 248 protocol-characterized soft switch technology. As many scholars have already pointed out, soft switches can also be seen in H. 323 and the result of smart gateway decomposition in the SIP System. In this way, the network architecture of the three technologies may be more clear. In fact, a true soft switch should be a general-purpose classless soft switch which undertakes the important responsibilities of regional or local system platforms in the Next Generation Network, it is capable of simultaneously controlling network access traffic and controlling edge interconnected traffic of the PSTN network. Regional general-purpose soft switches and National Core backbone networks can build a complete next-generation network communication system.

Conclusion

To sum up, soft switches are an important part of the call control, media control, and service provision and distribution systems for Voice/Data/video services in the next generation network. The next generation network not only requires a soft switch as a Technical Experiment of the local structure and scope, but also needs it as part of the entire IP telephone network architecture and H. 323 commercial practices integrating technologies such as SIP and other technologies. Many other problems related to the operation and governance of soft switches also need to be verified through the operation and implementation of the IP telephone network. Small-scale or laboratory tests of soft switches are of limited significance. Because the small network test mode is not necessarily suitable for the big network of Telecom IP, the small network test results in the laboratory do not necessarily fully explain the problems of the big network of Telecom IP. Therefore, only the test results of IP Phone applications in large production networks can fundamentally Promote the Development of the Next Generation Network.

The soft switch technology will face challenges in the process of large-scale integration with the IP telephone network and making it scalable, reliable, and operable. Telecom operators and equipment vendors should have reached a consensus on vision and cooperation, so as to work together to promote the depth and popularization of the correct concept of soft switches, we encourage you to explore innovative models of soft switches from different perspectives and advocate soft switches as new tools and means to drive new business models and create new market mechanisms. However, at the same time, it is necessary to solve the problems and challenges faced by technology moving towards the market so that technology can serve the business needs and business motivations of telecom operators, this will guide the entire industry to always adhere to the principles of business-oriented technology, user-oriented and business-oriented, so that the soft switch technology can provide the most comprehensive and systematic assurance for China Telecom operators to move towards the next generation network and enhance their competitiveness.