Push forward networks with Softswitch Technology

The development of networks is evolving from technology-driven to business-driven. Although the rapid development of the Internet and the emergence of a variety of data-type businesses are constantly emerging, the development of networks is subject to the existing telecom networks and IP network structures and technologies, how to achieve the integration of data and voice services, how to develop more and more services, and how to accelerate the pace of user-oriented business development to improve flexibility has become the driving force for the development of the entire information network. To this end, people provide value-added services through the intelligent network technology on the basis of traditional networks. However, the future network architecture oriented to grouping, broadband, and service represents the general trend of network evolution. In the future, the network will be a user-oriented network and an open business network.
As a functional entity, Softswitch provides Call Control and Connection Control functions for businesses with real-time requirements for the next generation network, and is the core of call and control for the Next Generation Network. To put it simply, Softswitch is an entity that implements the "Call Control" function of a traditional Programmable switch. However, the traditional "Call Control" function is integrated with the business, different services require different call control functions, while Softswitch is unrelated to services. This requires that the call control function provided by Softswitch is the Basic Call Control Function of various services. Softswitch will provide important support for Business independence and openness.

As an open entity, Softswitch must adopt an open protocol with external interfaces.

Interface between media gateway and SoftSwitch-this interface is used to control the bearer, resource control, and management of media gateway by SoftSwitch. This interface can use the Media Gateway Control Protocol (MGCP) or H.248, MEGACO Protocol.

The interface between the signaling gateway and the softswitch: used to transmit the signaling information between the softswitch and the signaling gateway. This interface can use signaling to control the transmission protocol (SCTP) or other similar protocols.

Interface between Softswitch-implement interaction between different SoftSwitch. This interface can use SIP-T or BICC protocol.

Interfaces between SoftSwitch and application/service layer: interfaces for accessing various databases, third-party application platforms, and various functional servers are provided to support various value-added services, management services, and third-party applications. For example:

Interface between SoftSwitch and Application Server: this interface can use the SIP protocol or API, such as Parlay, to provide support for third-party applications and various value-added services.

Interface between SoftSwitch and Policy Server: Implements dynamic intervention on the Work of network devices. This interface can use the COPS protocol.

Interface between SoftSwitch and gateway center: implements network management, which can use SNMP protocol.

Interface between SoftSwitch and SCP of Intelligent Network: to support existing intelligent network services, this interface can use the INAP protocol.

The main functions of softswitch include:

Media Gateway access function-this function can be considered as an adaptation function that can connect to various media gateways, such as PSTN/ISDN, IP relay media gateway, ATM media gateway, user media gateway, wireless media gateway, and data media gateway. You can also directly connect to the H.323 terminal and the SIP client terminal to provide services.

Call Control Function-call control is one of the important functions of SoftSwitch. It completes the establishment, maintenance, and release of basic calls and provides control functions, including call processing, Connection Control, smart call trigger detection, and resource control are the soul of the entire network.

Service provision function-as Softswitch plays a very important role in the process of evolution from circuit switching to sub-networking, Softswitch should be able to provide all the services provided by the PSTN/ISDN switch, it includes basic services and supplementary services. It should also be able to work with existing intelligent networks to provide services provided by existing intelligent networks.

Interconnection functions-currently, H.323 and SIP are two competing protocols in the group network. Among them, the H.323 protocol is the ITU-T standard, and the SIP protocol is the IETF standard, both of them can complete call establishment, release, service supplement, capability exchange, and other functions. The H.323 Protocol adopts the design concept of ISDN and uses the Q.931 protocol to establish and release a call. It is obviously characteristic of telecommunication network manageability and integration. At present, the H.323 protocol has been widely used on the Internet. In comparison with the SIP protocol, the H.323 protocol is more mature. Therefore, the IP address and telephone network of each operator in China currently use this protocol. The SIP protocol is simple, scalable, and closely related to existing Internet applications. Many people think that the Protocol is easy to implement and has developed rapidly in the near future, especially in the United States, at the same time, SIP will be widely used in the third-generation mobile communication core network and intelligent network. Multiple protocols are one of the main features of SoftSwitch. Therefore, Softswitch should support both Protocols at the same time.