Scheme of residual heat after the ingress network upgrades NGN

Current development dilemmas of domestic networks

After the restructuring, NGN and 3G represent the future direction of network development. The coexistence of multiple PSTN/NGN/3G networks will continue for a long time in the future, however, the existing render network and NGN are very different, and it is difficult to provide many personalized services that are easily provided in NGN, which is not conducive to the integration at the service layer. From the perspective of the local ISP networks that I participated in, the main problems faced by China's operators are as follows:

First, let's look at the existing network management system. Currently, the number of PSTN ports is too large, and the size of the Board is small and large, resulting in low network resource utilization and operational efficiency. In addition, incomplete mesh network connections between terminals and bureaus, as well as the integration of some ends and bureaus make the network layers unclear and the routes complicated, making maintenance and management more difficult.

Secondly, from the perspective of device management, there are a wide variety of local network terminal models, and the service provision capabilities are uneven, making it difficult to carry out value-added services across the network.

Fixed network operator's existing domestic network also encountered some difficulties in business development. Intelligent Network is currently the main method to provide value-added voice services for the PSTN, but it has shown great limitations. On the one hand, many end bureaus do not support SSPS. Most SSPs are independently created and attached to the PSTN network, making it difficult to quickly and uniformly launch smart services. On the other hand, the smart service trigger method is single. It only supports service trigger by access code. It does not support trigger by smart services without service access codes, such as caller authentication and called authentication. As a result, many new businesses cannot be implemented.

In addition, currently, user data in the PSTN is distributed, that is, the terminals and Exchange Board switches store and manage the user data respectively. This method has the disadvantages of preventing user data sharing.

In addition, from the perspective of the relationship between PSTN and PHS, PSTN and PHS are two independent networks, with no effective integration of network resources, number resources, customer resources, and management resources, it is difficult to carry out two-Network-Based Integrated Services.

How soft switches can be soft landing

For many local fixed-line network operators, the current huge domestic network is still its foundation, but the trend of PSTN fixed-line telephone revenue decline is inevitable. Voice services are being replaced by other communication methods such as SMS, E-mail, QQ, and VoIP. However, considering the relatively new vswitches, the utilization of devices is still very valuable, and the voice service is currently the most important telecom service, operators cannot give up on it at once.

At present, the maturity of softswitch applications in backbone networks is beyond doubt. However, after the introduction of backbone networks, due to the complexity of the end bureaus, business development also encountered difficulties. To solve this problem, operators tend to adopt the overlapping network development strategy. In the initial stage, the intercommunication between the softswitch network and the PSTN can be achieved through the interface bureaus or the exchange bureaus. In the middle and long term, with the gradual migration of PSTN users to the softswitch network, a local network can be integrated with multiple access modes, with Softswitch as the core. At the same time, the introduction of softswitch to the PSTN Local switching network is a gradual process. In the initial stage of its business development strategy, it can use new services to attract users. In the middle and long term, driven by new business applications, PSTN users are gradually migrated to the softswitch network, and the ingress network service is gradually evolving to the target network with Softswitch as the core.

Integration, adjustment and optimization

The author believes that at present, operators must prepare for the upgraded NGN network during network construction planning and adopt different strategies for the primary network, intelligent network, and Rural Network respectively.

After the Intelligent Transformation of the communications network, the Communications Board can be replaced by the relay gateway TG in the NGN, or the switch can be upgraded.

To achieve the above convergence, it is not recommended that you create a TDM telephone switch or narrowband voice access network device. You cannot use a TDM circuit switch to replace the device, the creation and expansion of TDM long-distance Circuit switches at DC2 level in the province are not allowed.

Existing intelligent networks can be integrated into NGN in two ways. The intelligent network can be upgraded to the service platform to be integrated into the NGN. The intelligent network can also be maintained in the original form and integrated into the NGN through interworking with the NGN service platform. Gradually reduce the size of the traditional PSTN network. If you have business needs and need to create new devices, you can select MSAN (Multi-Service Access Network) for network construction. Through the unified MSAN platform, you can access, integrate, and distribute multiple services, including voice, data, and leased lines. This allows you to connect POST services to the PSTN vswitch through V5, after grouping POST services, you can intervene in the softswitch network through the VOIP Ethernet interface, and achieve unified management of various services and resources. To avoid large-scale replacement of existing access networks, MSAN should be introduced to ensure smooth development of the NGN network with minimal changes to the existing network.

In rural areas, the transformation of optical fiber and integrated access equipment requires the transformation of local point sinking, while improving the broadband coverage in rural areas, synchronize and complete the adjustment of the speech service delivery area. In new rural areas, the user's cable access distance should be controlled within a certain distance, and comprehensive access equipment (MSAN) and ADSL2 + technologies should be deployed. For example, if the user's final capacity is larger than Y, the local IDC is used for construction. If the user's final capacity is smaller than Y, the outdoor integrated machine is used for construction. In administrative villages (natural villages), villages and towns (administrative villages) covered by optical cables, and areas that are close to each other and densely distributed, PON technology can be piloted to deploy ONU devices to provide voice and broadband services. (In this article, Y should be determined based on the actual situation .)

Pay attention to business needs during operation

On the management layer, fixed network operators should also determine the corresponding development principles based on network planning and business needs.

First, we should strictly control the selection and performance of equipment, and pay special attention to improving resource utilization. For example, when resizing a TDM circuit switch or narrowband voice access network device, you can expand the capacity of several existing devices without adding new racks. Check and create accounts for existing PSTN, module board, and access network device boards. If the switch and access network equipment need to be expanded, try to use the user board allocation method.

In addition, different device solutions should be used in different scenarios. For small and medium-sized enterprise users, new residential areas and rural areas, comprehensive access devices can be used to provide both broadband and voice access for users. The Softswitch AG device is mainly used to connect users with Softswitch voice and switch Switches of the existing end offices. For areas with a large user density, such as residential areas and commercial office buildings, Softswitch AG can be built to provide voice services. The PSTN switch of the backend server can be replaced by a large-capacity AG.

All in all, it is necessary to adapt to local conditions, improve the value of PSTN through network optimization and management optimization, reduce operation costs, and achieve "open-source and throttling ".

1. Mobile and fixed NGN integration solutions
2. NGN: Improving Softswitch technology to create a new business space