In-depth introduction to the structure and application of VoIP Broadband Access Network

This article introduces the structure and application of the VoIP broadband access network. Before giving you a detailed introduction to the VoIP broadband access network, we will first let you know how to prevent the VoIP broadband access network, and then give a comprehensive introduction, when I found this article to solve similar problems, I felt pretty good.

Evolution of network devices and structures of VoIP Broadband Access Networks

The traditional VoIP broadband access network architecture is based on the traditional gateway architecture with powerful functions and complex structures. Its biggest drawback is that the entire network is a "Blind network" with low intelligence and the network is uncontrollable, this causes no QoS Assurance for the voice quality. Based on the reality and application, and drawing on the experience of Traditional Telecom, the MGCP Media Gateway Control Protocol emerged in the VoIP broadband access network technology, separating the functions of traditional gateways.

The media exchange function and control function of the traditional gateway are separated, so that the gateway only undertakes the simple media transformation function. The complex control function is controlled by the centralized independent entity, that is, implementing SoftSwitch, in this way, the VoIP broadband access network is gradually developed into a centralized and smart structure. See network topology examples.

Benefits of using the network topology example:
◆ Provide highly reliable telephone services
◆ Compatible with existing user devices
◆ Provide new services more quickly
◆ Upgrade and maintenance are simple and quick.

The above network diagram shows the current local network topology of the new telecom operator. The functions of each device are as follows:
◆ Convergence switch: if the new telecom operator can operate local voice services and obtain number resources, it will receive the original PSTN traffic, or before the IP telephone equipment protocol standards are not unified, connect VoIP broadband access networks between different devices.
◆ Gateway GW): the PSTN voice is compressed and converted into an IP stream. It is also responsible for call processing, signaling and protocol conversion.
◆ IP/MAN: ip man, mainly composed of routers and switches.
◆ Call Command Center: Provides network user management and authentication, call routing information, and billing functions.
◆ Call management: it is called an agent. It is responsible for call establishment, release, persistence, transfer, and other call handling procedures for RGW/CPE users.
◆ Database/DHCP server: Responsible for user data management and dynamic IP Address allocation.
◆ RGW/CPE: A residential/user gateway device that connects to the user's PC with 10/100 Base, connects to a common telephone with 10/100 Base, and connects to a metropolitan area network with Base.

Several main elements of network networking

◆ Signaling streams are separated from media streams and voice streams. Call command centers, call management, and database/DHCP servers are only involved in the handling of call processes. Based on user information, establish and release the media channels and generate corresponding billing information. Media streams are transmitted only between RGW and CPE that need to exchange information over the IP metropolitan area network. If RGW/CPE is cross-network, they can be transmitted through a gateway switch.

◆ The IP address of each RGW/CPE can be a static public IP address, or a public or private IP address can be dynamically allocated by the DHCP server; while each network phone port of RGW/CPE does not require an IP address; when the computer accesses the Internet, the DHCP server dynamically allocates public or private IP addresses.

◆ The network phone number of each user follows the E.164 serial number principle. The IP address and port number of the RGW/CPE registered by the user correspond to the phone number assigned to the user.

◆ Each call command center can manage multiple call agents, each call agent can manage multiple RGW/CPE, and the call command center and call agent can be upgraded online, therefore, the capacity can be determined based on market requirements. The initial capacity is 0.1 million for the call command center and 2000 for the call agent. After the RGW is deployed, it is impossible to consider upgrading. Therefore, we should design the capacity of the RGW Based on the residential property in China. Generally, 10 LAN ports and 10 network telephone ports are recommended. CPE is used at home, so 1 LAN port and 2 network phones are recommended.

◆ Although the above scheme has not been applied on a large scale so far, its security and reliability, big talk processing capabilities, and so on need to be tested, its layout is not as limited as that of the traditional PSTN, the excellent scalability and comprehensive VoIP broadband access network capabilities will certainly be the best network construction for new telecom operators when they plan to carry out basic voice services.