Fixed network voice implementation method based on broadband core network

Abstract

The invention discloses a fixed network voice implementation method based on a broadband core network. Each fixed network voice device can access a plurality of backbone networks; comprising the steps of selecting and setting a voice service and establishing a voice service link layer; and a voice service session layer calling process. The method has the advantages that based on a broadband core network (BNC) architecture, a network transmission scheme of a control plane and a data plane of fixed network voice is reconstructed, broadband co-construction and sharing are achieved, the network construction and operation efficiency is improved, the network construction and operation cost is reduced, and the user experience is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of broadband network construction, and is particularly applicable to a fixed network voice implementation method based on a broadband core network. Background Art

[0002] Fixed-line voice refers to voice calls made through broadband networks, such as voice calls and videos under WIFI. Fixed-line IPTV connects the set-top box to the broadband network to provide users with video services such as digital TV viewing, on-demand, and playback.

[0003] Fixed-line voice and fixed-line IPTV rely on the home broadband network, access the optical modem provided by the backbone network operator through the router, and then access the optical distribution box of the backbone network operator through the wiring cabinet. Generally, the fiber-to-the-home facilities in residential areas are built by the building developer and the residential buildings at the same time. Each backbone network operator needs to lay out public optical cables and optical distribution facilities outside the residential buildings according to its own situation. When the user selects a backbone network operator, the backbone network operator will issue the company's optical modem to the user, and then connect the user's home optical fiber to its own optical distribution facilities. When the user changes the backbone network operator, the optical modem needs to be replaced, and the user's home optical fiber connection from the optical distribution facilities of other operators needs to be removed and then connected. This results in that in the same area, each backbone network operator needs to invest in a certain amount of public optical cables and optical distribution facilities. The user's choice preference will lead to a waste of resources invested by the operator and low efficiency. At the same time, when each telecommunications business operator performs fiber jump operations, there are often serious unsafe factors, which often lead to network failures, increase the number of network repair reports, and reduce user experience.

[0004] Broadband core network (BNC) is a new network architecture for broadband networks, which is mainly responsible for access control, service management and traffic forwarding of broadband services. Based on the concept of SDN technology, it realizes the separation of user plane and control plane of BNG network elements, and can open the separation of forwarding and control of BNC through standardized interfaces. How to improve the construction and operation efficiency of fixed networks, reduce construction and operation costs, and improve the user experience of fixed-line voice and fixed-line IPTV based on the new broadband core network (BNC) architecture has become an important direction for network optimization. Summary of the invention

[0005] The present invention aims to provide a method for implementing fixed network voice based on a broadband core network, aiming to solve the problems of low fixed network construction and operation efficiency and poor user experience of fixed network voice.

[0006] To achieve the above object, the present invention adopts the following technical solutions: The fixed network voice implementation method based on broadband core network described in the present invention, each fixed network voice device can access multiple backbone networks; including selecting and setting voice services, establishing voice service link layer; voice service session layer call flow; The steps of selecting and setting the voice service include: S1.1 The fixed network voice device enters the optical modem management system through the unique identity code of the user optical modem connected to the fixed network voice device; S1.2, the optical modem management system guides the user to enter the broadband service system of the selected backbone network operator, enter the user information and fixed-line voice service information and complete the payment, and obtain the fixed-line Internet account, password and phone number; S1.3, the broadband service system of the selected backbone network operator sends the user information and fixed network voice service information to the BSS system of the selected backbone network operator; S1.4, the BSS system synchronously updates the user's network access rights and service features to the backbone network operator's AAA system and soft switch system.

[0007] Furthermore, the voice service link layer establishment includes a link layer control plane process and a link layer data plane process; The link layer control plane process includes: S2.1.1, the user optical modem ONU connected to the fixed network voice equipment starts the IPOE process and broadcasts the DHCP message to the broadband core network pool end UP; S2.1.2, the broadband core network UP sends the message to the broadband core network CP for adjudication, and determines the backbone network operator corresponding to the fixed-line voice service of the fixed-line voice device by identifying the backbone network operator corresponding to the user's optical modem ONU; S2. 1.3, the broadband core network CP requests an address from the corresponding backbone network operator's DHCP server, selects an appropriate broadband core network UP to undertake the ONU business, and sends a forwarding flow table to the designated broadband core network UP; S2. 1.4, the designated broadband core network UP will convert the forwarding flow table into a local forwarding table entry; S2.1.5, the designated broadband core network UP unicasts a DHCP offer reply to the user optical modem ONU, and subsequent request / ack messages are unicasted between the user optical modem ONU and the broadband core network UP selected by the broadband core network CP.

[0008] Furthermore, the DHCP message includes an identifier of a backbone network operator selected by the user.

[0009] Furthermore, the link layer data plane process includes: S2.2.1, the user optical modem ONU connected to the fixed network voice equipment sends voice traffic to the broadband core network UP selected by the broadband core network CP; S2.2.2, the broadband core network UP routes and forwards the voice traffic to the core router CR of the corresponding backbone network operator; S2.2.3, the core router CR looks up the table and forwards the voice traffic to the backbone bearer network; the backbone bearer network forwards the voice traffic to the SBC server of the backbone network.

[0010] Furthermore, the destination MAC of the voice traffic is a virtual MAC of a designated broadband core network UP, and the source IP is an IP of the user's optical modem ONU.

[0011] Furthermore, the voice service session layer call process includes a session layer control plane process and a session layer data plane process; the session layer control plane process includes: S3.1.1, the fixed network voice device sends a call request through the connected user optical modem ONU; S3.1.2, the user's optical modem ONU converts the call request into a digital signal, which is sent via the optical fiber broadband network, access bearer network to the broadband core network UP, CP to the SBC server of the backbone network; S3.1.3, after the SBC server performs a security check, it selects an appropriate soft switch system to forward the call request according to the preset strategy or the backbone network core network soft switch specified by the user; S3.1.4, the soft switch system queries the called number routing table, obtains the user's routing information, and determines whether to accept the call; S3.1.5, if the call is accepted, the soft switch system forwards the call request to the SBC server or soft switch system where the called user is located; S3.1.6, after receiving the call request, the SBC server or soft switch system where the called user is located sends it to the ONU of the called user; S3.1.7, the ONU of the called user converts the call request into a voice signal and notifies the called user through the fixed network voice equipment; S3.1.8, after receiving the hang-up request, the soft switch system disconnects the call and releases related resources.

[0012] Furthermore, the session layer data plane process includes: S3.2.1, the user initiates a call, and the fixed network voice equipment converts the voice signal into an analog signal; S3.2.2, the user's ONU converts the analog signal into a digital signal and encodes it; S3.2.3, the encoded voice data is routed via the optical fiber broadband network, access bearer network to the broadband core network UP to the SBC of the backbone network specified by the user; S3.2.4, the SBC of the backbone network specified by the user encapsulates the encoded voice data and transmits it to the target soft switch device through the IP network; S3.2.5, after receiving the voice data, the target soft switch device performs decapsulation and decoding processing to restore the voice signal; S3.2.6, the decoded voice data is routed through the soft switch device and sent to the SBC where the called user is located; S3.2.7, SBC sends the voice data to the called user's ONU, and the ONU decodes the voice data and converts the digital signal into an analog signal; S3.2.8, plays the analog signal to the called user through the fixed network voice equipment.

[0013] The advantages of the present invention are that based on the broadband core network (BNC) architecture, the network transmission scheme of the control plane and data plane of fixed-line voice is reconstructed, broadband co-construction and sharing is realized, the efficiency of network construction and operation is improved, the cost of network construction and operation is reduced, and the user experience is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 The figure is a schematic diagram of selecting and setting the fixed network voice service in the method of the present invention.

[0015] Figure 2 The present invention is a flow chart of the control plane of the link layer of the fixed network voice service in the method of the present invention.

[0016] Figure 3 The figure is a schematic diagram of the data plane flow of the link layer of the fixed network voice service in the method of the present invention.

[0017] Figure 4 The present invention is a flow chart of the control plane of the session layer of the fixed network voice service in the method of the present invention.

[0018] Figure 5 The present invention is a flow chart of the data plane of the session layer of the fixed network voice service in the method of the present invention. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] In the present invention, fixed-line voice service refers to the fixed-line voice service provided by the backbone network (service) operator through the soft switch system on the broadband integrated bearer network. The user's fixed telephone terminal accesses the BNC network through dialing, and then realizes the interaction of called terminal paging and traffic through the soft switch system. Voice service user traffic is divided into control plane traffic used for authentication, access and other operations, and data plane traffic to realize user traffic traffic interaction.

[0021] The fixed-line voice implementation method based on broadband core network described in the present invention is based on a new broadband core network (BNC) architecture. The broadband core network (BNC) architecture is based on the technical concept of SDN, which can realize the separation of the user plane and the control plane of the broadband network gateway BNG network element; and then adopt cloud native technology to realize the cloud-based intensive deployment of the management layer and the control plane network element. The network functions of the control plane are further defined as a number of "service" modules that can be flexibly called, which can realize the modular deployment of different functions of the BNG control plane, decoupling between modules, and elastic expansion of different modules; realize load sharing among multiple modules with the same function; realize plug-and-play of functional units through automatic discovery and registration of functional units, and adopt standardized API interfaces to realize the openness of BNC capabilities.

[0022] The broadband core network BNC mainly includes the broadband core network control plane (BNC-CP) and the broadband core network user plane (BNC-UP).

[0023] The BNC control plane includes the control plane functions (CTRL, UPMNG, ACC, etc.) of the traditional broadband network gateway (BNG), RADIUS server, DHCP server, as well as CDN control plane, intelligent business analysis (CAM) and other network elements to realize functions such as user access control and business management. In the future, the control plane network elements should evolve towards a service-oriented architecture. The various control plane network elements should be interconnected using service-oriented interfaces, and the necessary control plane network elements should be selected and deployed according to the needs of network business development.

[0024] The BNC user plane is mainly responsible for user service traffic forwarding and traffic control. According to business development needs, it deploys SAC / SAD network elements on demand to provide business intelligent perception and value-added services, and deploys CDN resource pools to provide CDN services.

[0025] The broadband core network is managed by a unified BNC management and control system, which is responsible for the management and operation of the BNC system, service status monitoring, alarm management, rapid fault location and demarcation, service configuration, etc. Each BNC network element and management and control system should support IPv4 / IPv6 dual-stack mode and IPv6 single-stack mode.

[0026] Among them, the main functions of the BNC control plane include CTRL control module, UPMNG management module, ACC access module, AAA responsible for authentication, authorization and billing function module, DHCP address module, CAM and CDN control plane modules. CTRL is responsible for allocating IP addresses to users and interacting with various servers. UPMNG is responsible for UP device status management, sending configurations to the broadband core network user plane UP, creating and distributing forwarding table entries. ACC is responsible for processing PPPoE and DHCP dial-up messages. AAA is responsible for authentication, authorization and billing functions. DHCP is responsible for address management and allocation. CAM is a central analysis platform that collaborates with the intelligent traffic collection unit and is responsible for collecting user flow logs and policy coordination. The CDN control plane is responsible for policy control of CDN, etc.

[0027] The main functions of the BNC user plane include BNC-UP, SAU, CDN and other modules. The BNC-UP module is responsible for completing functions such as user service traffic forwarding and traffic control, including: traffic forwarding, QoS, traffic statistics, unicast routing protocol, multicast routing protocol, SRv6 and other forwarding plane functions. The SAU service perception unit is responsible for completing service collection, analysis and reporting functions, including: SAC (card-type service perception unit) and SAD (stand-alone service perception unit). The CDN content provision module is responsible for providing content services to users.

[0028] In the fixed network voice implementation method based on broadband core network described in the present invention, each fixed network voice device can access multiple backbone networks; the specific implementation process includes three processes: selecting and setting voice services, establishing voice service link layer; and voice service session layer call flow.

[0029] like Figure 1 As shown, the steps of selecting and setting the voice service include: S1.1 The fixed-line voice device enters the optical modem management system through the unique identity code of the user's optical modem connected to the fixed-line voice device. Generally, a QR code representing the unique identity of the optical modem is set on the surface of the optical modem ONU (can be posted externally). Users can scan the code to enter the APP, mini program or public account. The APP, mini program or public account will update the selection information of the backbone network operator to the RMS optical modem management system. The RMS optical modem management system pushes the user's selection of the service network (the first backbone network, the second backbone network, and the Nth backbone network's services) to the optical modem ONU corresponding to the user's home.

[0030] S1.2, the optical modem management system guides the user to enter the broadband service system of the selected backbone network operator, enter the user information and fixed-line voice service information and complete the payment, and obtain the fixed-line Internet account, password and phone number. The user can also modify the password by himself.

[0031] S1.3, the broadband service system of the backbone network operator selected by the user sends the user information and fixed-line voice service information, including the user's Internet account and password, the user's identity information, service selection information, and fixed telephone number to the BSS system of the selected backbone network operator.

[0032] S1.4, the BSS system synchronously updates the user's network access rights and service features to the backbone network operator's AAA system and soft switch system.

[0033] At this point, the user has completed the backbone network operator selection and service settings for the fixed-line voice service and can start the fixed-line voice service.

[0034] The development of fixed voice services is generally divided into two levels: The first level is to realize the connection of the link layer first. Through the decision of the broadband core network CP, the user's ONU is connected to the first backbone network, so that the user network and the SBC and soft switch of the first backbone network can achieve link access.

[0035] The second layer is the connection at the voice session layer, which enables the voice gateway in the ONU to establish a session layer connection with the soft switching system of the first core network through the SBC of the first backbone network, and realize the communication of telephone services under the signaling scheduling of the soft switching system of the first core network.

[0036] The architecture of the broadband core network is similar to that of the soft-switched core network, both of which are control and bearer separation architectures. Therefore, the link layer and session layer mentioned above each include service flows of the control plane and the data plane. That is, the voice service link layer establishment includes the link layer control plane flow and the link layer data plane flow. The voice service session layer call flow includes the session layer control plane flow and the session layer data plane flow.

[0037] Specifically, if Figure 2 As shown, the link layer control plane process includes: S2.1.1, the user optical modem ONU connected to the fixed network voice equipment starts the IPOE process, and broadcasts the DHCP message to the broadband core network pool end UP through the OLT.

[0038] S2.1.2, the broadband core network UP encapsulates the message into the VXLAN tunnel and sends it to the broadband core network CP for decision. The message sent includes the backbone network operator's ID. The broadband core network CP identifies the backbone network operator corresponding to the user's optical modem ONU by identifying the backbone network operator's ID, and determines the backbone network operator corresponding to the fixed-line voice service of the fixed-line voice device.

[0039] S2.1.3, the broadband core network CP requests an address from the corresponding backbone network operator's DHCP server, selects a suitable broadband core network UP to undertake the ONU service, and sends a forwarding flow table to the designated broadband core network UP.

[0040] S2. 1.4, the designated broadband core network UP converts the forwarding flow table into a local forwarding table entry.

[0041] S2.1.5, the designated broadband core network UP unicasts a DHCP offer reply to the user optical modem ONU, and subsequent request / ack messages are unicasted between the user optical modem ONU and the broadband core network UP selected by the broadband core network CP.

[0042] like Figure 3 As shown, the link layer data plane process includes: S2.2.1, the user optical modem ONU connected to the fixed network voice equipment sends voice traffic to the designated broadband core network UP, where the destination MAC of the voice traffic is the designated broadband core network UP virtual MAC, and the source IP is the user optical modem ONU.

[0043] S2.2.2, the broadband core network UP routes and forwards the voice traffic to the core router CR of the corresponding backbone network operator.

[0044] S2.2.3, the core router CR looks up the table and forwards the voice traffic to the backbone bearer network; the backbone bearer network forwards the voice traffic to the SBC server of the backbone network.

[0045] like Figure 4 As shown, the session layer control plane process includes: S3.1.1, the user sends a call request through the fixed network voice device connected to the user's optical modem ONU. The call request is designated to the core network soft switch of the backbone network to be connected.

[0046] S3.1.2, the user's optical modem ONU converts the call request into a digital signal, which is transmitted via the optical fiber broadband network, access bearer network to the broadband core network UP, CP to the SBC server of the backbone network.

[0047] S3.1.3, after receiving the call request, the SBC server first performs a security check to ensure that the request comes from a legitimate user and device. After that, the SBC server selects the most appropriate soft switch system to forward the call request according to the preset strategy, such as load balancing, network status, etc., or the backbone network soft switch system specified by the user.

[0048] In addition, the SBC server needs to perform necessary address conversion and protocol adaptation on the call request to ensure that it can be correctly identified and processed by the target soft switch system (i.e., the backbone network soft switch system where the called user is located).

[0049] S3.1.4, after receiving the call request, the target soft switch system performs call control processing according to the user information and business logic, which mainly includes the soft switch system querying the called number routing table of the designated backbone network, obtaining the user's routing information, and determining whether to accept the call.

[0050] S3.1.5, if the call is accepted, the soft switch system forwards the call request to the SBC server or soft switch system where the called user is located; if the called user is also in the same core network, the connection may be made directly through internal routing.

[0051] S3.1.6, after receiving the call request, the SBC server or soft switch system where the called user is located sends the call request to the ONU of the called user.

[0052] S3.1.7, the ONU of the called user converts the call request into a voice signal and notifies the called user through the fixed network voice equipment. After the called user answers the call, the two parties start a voice call.

[0053] S3.1.8, when the call ends, either party can initiate a hang-up request. The hang-up request is transmitted and processed through the same path. After receiving the hang-up request, the soft switch system disconnects the call and releases related resources.

[0054] like Figure 5 As shown, the session layer data plane process includes: S3.2.1, the user initiates a call, and the fixed-line voice equipment converts the voice signal into an analog signal.

[0055] S3.2.2, the user's ONU converts the analog signal into a digital signal and encodes it (such as G.711, G.729, etc.) for transmission on the IP network.

[0056] S3.2.3, the encoded voice data is routed via the optical fiber broadband network, access bearer network to the broadband core network UP to the SBC of the backbone network specified by the user; S3.2.4, the SBC of the backbone network specified by the user encapsulates the encoded voice data (such as RTP / RTCP encapsulation) and adds necessary signaling information (such as SIP signaling) to ensure the integrity and reliability of data transmission.

[0057] The encapsulated voice data is transmitted to the target soft switch device through the IP network.

[0058] S3.2.5, after receiving the voice data, the target soft switch device performs decapsulation and decoding processing to restore the original voice signal.

[0059] S3.2.6, the decoded voice data is sent to the SBC where the called user is located through the internal routing of the target soft switch device.

[0060] S3.2.7, SBC sends the voice data to the ONU of the called user, and the ONU decodes the voice data and converts the digital signal into an analog signal.

[0061] S3.2.8, the user's ONU plays the analog signal to the called user through the fixed network voice equipment.

[0062] The SBC mentioned in the present invention is a Session Border Controller. SBC has security protection functions and can prevent denial of service (DoS) attacks, distributed denial of service (DDoS) attacks, etc. For example, when a network is hit by a large amount of malicious traffic trying to impact a communication session, SBC can identify and block these abnormal traffic to protect the session security of the internal network. It can detect signaling and media streams and filter out illegal access requests, just like a security firewall in network communication.

[0063] SBC also has the function of network address translation (NAT) traversal. In IP communication, the existence of address translation (NAT) between private and public networks can cause problems in session establishment. SBC can achieve NAT traversal, allowing terminal devices in different network address environments to successfully establish and maintain communication sessions. For example, when an IP phone in an enterprise's internal private network is talking to other communication devices in an external public network, SBC can help solve the communication barriers caused by address translation.

[0064] SBC also supports multiple communication protocols and can achieve conversion between different protocols. For example, in a soft switch network, there may be SIP (Session Initiation Protocol), H.323 and other protocols. SBC can convert and adapt between these different protocols, so that devices using different protocols can have effective session communication. At the same time, it can also handle boundary session management between different service provider networks to ensure the quality and compliance of cross-network communication.

[0065] SBC can optimize media streams, such as adjusting the encoding format and bandwidth of voice or video. For example, when the media encoding formats of two terminal devices are inconsistent, SBC can transcode the media stream so that both parties can communicate normally. It can also monitor the quality of the media stream. When it finds that the media quality has deteriorated (such as network congestion causing voice jams or blurred video images), it takes corresponding measures to improve the communication quality, such as adjusting the transmission path or bandwidth allocation.

Claims

1. A method for implementing fixed network voice based on broadband core network, characterized in that: Each fixed-line voice device can access multiple backbone networks; Including selecting and setting up voice services, and establishing the voice service link layer; Voice service session layer call flow; The steps of selecting and setting the voice service include: S1.1 The fixed network voice device enters the optical modem management system through the unique identity code of the user optical modem connected to the fixed network voice device; S1.2, the optical modem management system guides the user to enter the broadband service system of the selected backbone network operator, enter the user information and fixed-line voice service information and complete the payment, and obtain the fixed-line Internet account, password and phone number; S1.3, the broadband service system of the selected backbone network operator sends the user information and fixed network voice service information to the BSS system of the selected backbone network operator; S1.4, the BSS system synchronously updates the user's network access rights and service features to the backbone network operator's AAA system and soft switch system.

2. The method for implementing fixed network voice based on broadband core network according to claim 1, characterized in that: The voice service link layer establishment includes a link layer control plane process and a link layer data plane process; The link layer control plane process includes: S2.1.1, the user optical modem ONU connected to the fixed network voice equipment starts the IPOE process and broadcasts the DHCP message to the broadband core network pool end UP; S2.1.2, the broadband core network UP sends the message to the broadband core network CP for adjudication, and determines the backbone network operator corresponding to the fixed-line voice service of the fixed-line voice device by identifying the backbone network operator corresponding to the user's optical modem ONU; S2. 1.3, the broadband core network CP requests an address from the corresponding backbone network operator's DHCP server, selects an appropriate broadband core network UP to undertake the ONU business, and sends a forwarding flow table to the designated broadband core network UP; S2. 1.4, the designated broadband core network UP will convert the forwarding flow table into a local forwarding table entry; S2.1.5, the designated broadband core network UP unicasts a DHCP offer reply to the user optical modem ONU, and subsequent request / ack messages are unicasted between the user optical modem ONU and the broadband core network UP selected by the broadband core network CP.

3. The method for implementing fixed network voice based on broadband core network according to claim 2, characterized in that: The DHCP message includes the identifier of the backbone network operator selected by the user.

4. The method for implementing fixed network voice based on broadband core network according to claim 2, characterized in that: The link layer data plane process includes: S2.2.1, the user optical modem ONU connected to the fixed network voice equipment sends voice traffic to the designated broadband core network UP; S2.2.2, the broadband core network UP routes and forwards the voice traffic to the core router CR of the corresponding backbone network operator; S2.2.3, the core router CR looks up the table and forwards the voice traffic to the backbone bearer network; The backbone bearer network forwards voice traffic to the SBC server of the backbone network.

5. The method for implementing fixed network voice based on broadband core network according to claim 4, characterized in that: The destination MAC of the voice traffic is the virtual MAC of the designated broadband core network UP, and the source IP is the IP of the user's optical modem ONU.

6. The method for implementing fixed network voice based on broadband core network according to claim 2, characterized in that: The voice service session layer call process includes a session layer control plane process and a session layer data plane process; The session layer control plane process includes: S3.1.1, the fixed network voice device sends a call request through the connected user optical modem ONU; S3.1.2, the user's optical modem ONU converts the call request into a digital signal, which is sent via the optical fiber broadband network, access bearer network to the broadband core network UP, CP to the SBC server of the backbone network; S3.1.3, after the SBC server performs a security check, it selects an appropriate soft switch system to forward the call request according to the preset strategy or the backbone network core network soft switch specified by the user; S3.1.4, the soft switch system queries the called number routing table, obtains the user's routing information, and determines whether to accept the call; S3.1.5, if the call is accepted, the soft switch system forwards the call request to the SBC server or soft switch system where the called user is located; S3.1.6, after receiving the call request, the SBC server or soft switch system where the called user is located sends it to the ONU of the called user; S3.1.7, the ONU of the called user converts the call request into a voice signal and notifies the called user through the fixed network voice equipment; S3.1.8, after receiving the hang-up request, the soft switch system disconnects the call and releases related resources.

7. The method for implementing fixed network voice based on broadband core network according to claim 5, characterized in that: The session layer data plane process includes: S3.2.1, the user initiates a call, and the fixed network voice equipment converts the voice signal into an analog signal; S3.2.2, the user's ONU converts the analog signal into a digital signal and encodes it; S3.2.3, the encoded voice data is routed via the optical fiber broadband network, access bearer network to the broadband core network UP to the SBC of the backbone network designated by the user; S3.2.4, the SBC of the backbone network specified by the user encapsulates the encoded voice data and transmits it to the target soft switch device through the IP network; S3.2.5, after receiving the voice data, the target soft switch device performs decapsulation and decoding processing to restore the voice signal; S3.2.6, the decoded voice data is routed through the soft switch device and sent to the SBC where the called user is located; S3.2.7, SBC sends the voice data to the ONU of the called user, and the ONU decodes the voice data and converts the digital signal into an analog signal; S3.2.8, plays the analog signal to the called user through the fixed network voice equipment.

Images