How does the Softswitch technology provide and transfer multiple services?

There are many areas worth learning about the Softswitch technology. Here we mainly introduce how the Softswitch technology provides and transfers multiple services. The purpose of the network is to provide effective communication means, its user-level interfaces are various services. Users care about cheap and easy-to-use services, such as phones, on-demand videos, and multimedia text messages. network operators are concerned about how to provide these services at a low cost but efficiently. Technology is always lagging behind people's potential needs, although technology is constantly improving.

As long as you look at all the current networks, including PSTN, Internet and wireless networks, and provide a variety of discrete and poor services, the fact that technology lags behind demand is obvious. Specifically, the technical deficiencies come from both sides: one is the lack of telecommunication network technology, and the other is the lack of TCP/IP network technology.

The disadvantages of both are cost problems. The circuit switching technology used by telecom networks cannot efficiently carry unexpected services, such as data, compressed images, and compressed videos, these will be mainstream communication services in the future. Traditional Telecom networks cannot provide interfaces for these services, while ATM is too costly to get started. Although the cost of TCP/IP network is low and all services are supported, it cannot guarantee that service provision can satisfy users. Therefore, the primary problem of the Next Generation Network (NGN) is to solve the convergence of telecommunication networks and TCP/IP networks-integration at various layers, including the physical layer, transmission layer, control layer, and service layer. This convergence will absorb the advantages of the two types of networks and improve their shortcomings.

Adapting to a variety of services means that the network will have different intelligence, which is the problem to be solved by intelligent exchange or Softswitch technology. The Softswitch technology will solve the problem of fast creation and deployment of a variety of services and new services, and greatly reduce operation costs by fully adopting the group exchange technology at the transport layer. This is very interesting, because in the past, the TCP/IP network used the telecommunication network circuit to transmit its data packets, but now the telecommunication network has to use the grouped data network as its transmission layer technology.

Gradient rather than revolution

The Softswitch technical system includes the media access control system, business support system, transmission system, and control system. These aspects are independent, there are many protocol standards, and the development level is also different, but the evolution of different subsystems together constitutes a new softswitch system architecture. The evolving and integrated technologies include all network layers:

Integration of the access layer: the core network uses a relatively simple technology, such as SDH and DWDM. The access network has multiple features, such as data user access, analog user access, ISDN access, V5 access, and relay access. The integration of the access layer is reflected in the segmentation transformation of traditional facilities, such as the recent emergence of VDSL + Ethernet technology. This will be an important step towards NGN, because the access network is directly oriented to a large number of users and occupies 80% of the total infrastructure. The access layer device of Softswitch technology is a media gateway, responsible for the conversion and control of different access technologies.

Integration of the transport layer: TCP/IP technology will be fully used, but the connectionless feature of TCP/IP technology is not suitable for service QoS requirements. Therefore, it must be supplemented by the control layer protocol, to provide satisfactory transmission, such as MPLS and traffic engineering. The devices in this area are mainly improved routers and switches. The new routing devices will not only provide the best-effort service, but also use complex Queue Management Algorithms Based on the Control Information provided by the control layer, provides quantitative transmission effects to support classified businesses.
Integration of control layer: the control layer is closely related to the business and needs to deal with various systems, such as routers, application servers, and database subsystems. This is part of the true embodiment of network intelligence. Traditional signaling and routing protocols are combined with semantic transformations), or independent protocols are used to respond to various business needs and control the network elements.

Integration of the business layer: the service creation and provision of NGN are more convenient and flexible, and standard APIs are adopted. By providing a platform based on standard APIs, operators can quickly create new businesses and quickly implement them using the intelligence of the Softswitch technology system. The advantage is that the separation of business and call control is conducive to introducing competition at the business layer. The progress in this area includes Parlay standards, including API support for communication, information, messaging, entertainment, billing, and other services. The H.323 protocol is also an application layer protocol. Its original intention is mainly for video conferencing services. However, in the past two years, it has been applied in VoIP, and ITU continues to expand H.323, to provide a wider range of capabilities, such as support for multimedia services.

Convergence from products

Technological updates are a slow process. The goal of the Softswitch technology is the next generation network, but the technology and equipment updates are gradual. At present, the Softswitch technology is driven by both sides of the Telecom and data camps. The former includes old telecom manufacturers such as Nortel, LUCent, and EriCsson, while the latter includes Sun, Microsoft, Cisco, and 3Com. Of course, in view of their own experience, different manufacturers will have their own focus on different aspects of SoftSwitch. Manufacturers from the data network camp will pay more attention to QoS Assurance for TCP/IP networks and the implementation of service layer protocol standards; telecommunications vendors provide updated devices at the control and media access layers of the network.

At present, the new generation of softswitch products are still in the testing stage, but some of the above mentioned products in the field of Softswitch technology have been used early, such as video conferencing systems based on the H.323 protocol stack and IP Telephone Gateway systems, and is gradually improving and planning to replace the complicated H.323 SIP protocol.

Progress and objectives

There is no mature experience in building networks based on Softswitch technology at home and abroad. The main problem is that due to the lack of large-scale actual network operations, the overall performance test of the softswitch system can only be carried out in a small network, the test results cannot be simply analogous to large-scale networking. Therefore, the main task at present is to obtain the real performance prediction results of softswitch from the test network's Softswitch practice. As for the key role of softswitch in the development of networks, the successful implementation of the softswitch architecture remains to be seen.