Broadband core network deployment method based on forwarding and control separation

Abstract

The invention discloses a broadband core network deployment method based on forwarding and control separation. A broadband core network control plane is deployed in a provincial centralized manner and is deployed in a different-address or different-place 1 + 1 hot standby manner; broadband core network user planes are deployed in a centralized manner according to cities and different local addresses are in 3 + 1 warm standby; control planes of the broadband core network communicate with each other through MER equipment, are borne by using L3VPN, and are connected to an intelligent metropolitan area network by using the MER equipment to communicate with CR equipment; the broadband core network user plane double-uplink different-local-address two CRs are incorporated into the autonomous domain management of the metropolitan area network, and uplink broadband core network control plane and downlink OLT equipment are connected through the intelligent metropolitan area network. Compared with a traditional BRAS, under the same hardware condition, the number of supported users is larger, forwarding plane resources are utilized more efficiently, and the capacity expansion requirement is lowered; the IP addresses can be controlled in a centralized mode, applied and distributed according to needs, automatically released after being used, efficiently used and easy to operate, maintain and manage.

Description

Technical Field

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

[0002] The metropolitan area network mainly includes a core router (CR, Core Router), a service router (SR, Service Router), a broadband remote access server (BRAS, Broadband Remote Access Server), and an aggregation switch (SW, Switch).

[0003] The traditional BRAS is located in the service control layer of the metropolitan area data network, responsible for functions such as broadband access, authentication, authorization, and charging, managing the bandwidth allocation and service traffic aggregation of broadband users, completing the connection of broadband users such as PPPoE and IPoE (IP over Ethernet), and also providing services such as value-added services. The BRAS device serves both as a home broadband access Internet gateway and as a three-layer edge of the IP network, making the control plane and the forwarding plane tightly coupled. Although the BRAS device has a strong traffic forwarding ability, small traffic such as ITMS (Integrated Terminal Management System) services and VoIP services occupies a large amount of session (a session is a software user entry of the BRAS, usually a session occupies a user license, allocates a user ID, and is a performance parameter used by the device to control users) concurrency capabilities, resulting in mutual influence between the session and memory of the device in processing, unable to fully utilize the forwarding and access capabilities of the device, difficult to reuse and share the VLAN of the BRAS, and even unable to solve the fundamental problem even with the QINQ technology (also known as Double VLAN, double-layer VLAN); and different VLAN domains are isolated from each other and cannot communicate with each other. As the number of users continues to increase, the network configuration and management difficulty continue to increase.

[0004] At present, the business scope of broadband is changing from a single ToH business to a composite ToB / ToH business. The business scenarios are diverse and the business requirements are changeable, requiring the core capabilities of the broadband network to change from simple service access capabilities to service-oriented service control, innovation, and operation capabilities, evolving from traditional broadband services to future fixed-mobile convergence access and cloud-network collaborative service directions.

[0005] In order to achieve this goal, the "optical access network + BNG + network operation support" will be reconstructed into a new end-to-end broadband network. Referring to the concept of the 5G core network, the broadband network gateway will be promoted to evolve into the broadband network core network BNC. Enhancing service-oriented business control and innovative service capabilities has become a technical problem that needs to be solved urgently. Summary of the invention

[0006] The present invention aims to provide a broadband core network deployment method based on transfer and control separation, aiming to solve the current deployment problem of broadband network gateway evolution to broadband network core network with transfer and control separation.

[0007] To achieve the above object, the present invention adopts the following technical solutions: The broadband core network deployment method based on separation of forwarding and control described in the present invention is that the broadband core network control plane is centrally deployed by province, and is deployed in different addresses or 1+1 hot standby in different places; the broadband core network user plane is centrally deployed by city, and is deployed in different local addresses with 3+1 warm standby; the broadband core network control planes are interconnected through MER equipment, using L3VPN bearer, and using MER to access the intelligent metropolitan area network and communicate with CR equipment; the broadband core network user plane is dually connected to two CRs at different local addresses, included in the metropolitan area network autonomous domain management, and connected to the broadband core network control plane through the intelligent metropolitan area network, and connected to the OLT equipment below.

[0008] Preferably, when the OLT device is connected to the broadband core network user plane through a convergence device, the broadband core network user plane is centrally deployed by city and prefecture, and 1+1 warm standby is adopted.

[0009] Preferably, the OLT device is connected to the broadband core network user plane via a layer 2 aggregation device, and performs service distribution and port aggregation on the OLT via a layer 2 transparent transmission method.

[0010] Preferably, the broadband core network control plane communicates with the external server via Native IP and the public network plane.

[0011] Preferably, the OLT device is connected to the intelligent metropolitan area network in a QinQ manner, and EVPN VPLS is deployed between the MER in the aggregation area and the MER in the user plane of the broadband core network, and the outer VLAN of the OLT message is matched to introduce the traffic into the EVPN VPLS instance.

[0012] The advantages of the present invention are as follows. Compared with traditional BRASs, in the broadband core network deployment based on separation of control and forwarding, the control functions are centrally managed in the cloud. Under the same hardware conditions, it can support a larger number of users, utilize forwarding plane resources more efficiently, and reduce the expansion requirements; it can centrally control IP addresses, apply for allocation on demand, automatically release them after use, and use them efficiently. The operation and maintenance management is simple, and there is a single connection with the logical structure of the service system, simplifying the docking of the service system; the processing speed of user on-line packets and control packets will be greatly improved, effectively avoiding the avalanche effect under the pressure of a large number of users; at the same time, the user plane increases the basic configuration of the forwarding plane device, and the control plane can be independently upgraded, greatly shortening the service on-line cycle and significantly improving the efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the broadband core network deployment with separation of control and forwarding according to the present invention.

[0014] Figure 2 It is a schematic diagram of the bearer between CPs of the broadband core network with separation of control and forwarding according to the present invention.

[0015] Figure 3 It is a schematic diagram of the bearer between CP and CR of the broadband core network with separation of control and forwarding according to the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0016] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0017] As Figure 1 shown, in the broadband core network deployment method based on separation of control and forwarding according to the present invention, the broadband core network BNC adopts a deployment mode of separating the broadband core network control plane CP and the broadband core network user plane UP. The broadband core network control plane CP is centrally deployed by province, and adopts a cross-machine room different-site or off-site 1+1 hot standby deployment. The broadband core network control plane CP is respectively deployed in two core computer rooms, which can ensure the security of the CP. At the same time, the broadband core network control plane CP adopts a different-site hot standby mode of deployment to ensure the reliability of the CP. Real-time synchronization of user data is carried out between the primary and standby broadband core network control planes CP; to ensure fast service switching in case of faults. AAA (authentication, authorization, and accounting system) and DHCP Server, etc. utilize existing equipment.

[0018] MER devices are set up in the computer room where the control plane CP of the broadband core network is located. The control plane CPs of the broadband core network at different sites or in different locations communicate with each other through MER devices and use L3VPN for bearer. That is, the sub-interface of the MER at the CP pool end of the broadband core network is configured to bind to the L3VPN instance, and the traffic path is CP1 - MER at the pool end - CP2. As Figure 2 shown. Among them, CP1 and CP2 are two different control planes CPs of the broadband core network deployed at different sites or in different locations. The MER at the pool end is the MER device set up in the computer room where CP1 and CP2 are located.

[0019] The user plane UP of the broadband core network is deployed in a centralized pool by city and is located in the core computer room of the city, with 3 + 1 warm standby at different bureau locations. The user plane UP of the broadband core network is dual - uplinked to two CRs (core routers) at different bureau locations, and the routing organization between the user plane UP of the broadband core network and the CRs is consistent with that of the traditional BNG. The user plane UP of the broadband core network is incorporated into the management of the metro area autonomous domain. At the same time, the user plane UP of the broadband core network is uplinked to the control plane CP of the broadband core network through the intelligent metro network and downlinked to the OLT device.

[0020] Specifically, when the user plane UP of the broadband core network is uplinked to the control plane CP of the broadband core network through the intelligent metro network, both the user plane UP of the broadband core network and the control plane CP access the MCR of the intelligent metro network through the MER to realize the transmission of signaling information between them. The control plane CP also accesses the MCR of the intelligent metro network through the MER to realize the connection with the CR device. It communicates with external servers (such as RADIUS servers, DHCP servers, etc.) through the public network plane using Native IP, as Figure 3 shown.

[0021] The OLT device is uplinked to the user plane UP of the broadband core network, including access through the MER of the intelligent metro network or through the aggregation of switches. When the OLT device is uplinked to the user plane UP of the broadband core network through the aggregation device, the user plane UP of the broadband core network is deployed in a centralized manner by city and adopts 1 + 1 warm standby. The OLT device is directly connected to the user plane UP of the broadband core network through the fiber of the layer - 2 aggregation device, and the service distribution and port aggregation of the OLT are carried out in a layer - 2 transparent transmission manner. The service flow is OLT - aggregation switch - user plane UP of the broadband core network.

[0022] When the OLT device accesses the user plane UP of the broadband core network through the MER of the intelligent metro network, an MER device is set up in the computer room where the user plane UP of the broadband core network is located. The OLT accesses the MER device of the intelligent metro network in the form of QinQ. At the same time, EVPN VPLS is deployed between the MER in the aggregation area and the MER of the user plane of the broadband core network to match the outer VLAN of the OLT packet and introduce the traffic into the EVPN VPLS instance.

[0023] After adopting the broadband core network deployment method based on separation of transfer and control described in the present invention, the bearing processes of home broadband services, IPTV on-demand service bearing processes, IPTV multicast service bearing processes, voice service bearing processes, home gateway management service bearing processes, and Internet dedicated line service bearing processes will all be optimized and adjusted accordingly.

[0024] For the home broadband service bearing process, during dial-up authentication, the ONU starts the PPPOE process, broadcasts the PADI message to all UPs at the pool end, and the UP encapsulates the message into a VxLAN tunnel and sends it to the CP for adjudication. The CP selects a suitable UP to bear the service of this ONU; unicasts a PADO back to the ONU, and subsequent PADR / PADS messages are all sent unicast between the ONU and the designated UP.

[0025] The ONU starts the PPP three-stage negotiation process. The CP completes the authentication interaction between this ONU and the AAA. After successful authentication, the CP assigns an address. After the ONU passes the authentication, it obtains the address and completes the three-stage negotiation interaction; the CP issues a forwarding flow table to the UP, and the UP converts the received flow table into a local forwarding entry; the CP requests to start the charging process. The service traffic path is ONU-OLT-MER-MCR-UP pool end MER-UP-CR.

[0026] For the IPTV on-demand service bearing process, during dial-up authentication, the user terminal initiates an IPoE dial-up, and the initiated DHCPDiscover message reaches the UP pool through the OLT and the intelligent network. All UPs receive the dial-up traffic; the UP, as the user gateway, sends the DHCP message to the CP through the VxLAN channel; the CP relays the DHCP request message to the DHCP server, and the DHCP server sends the request message to the Radius server to complete the AAA authentication; the CP selects a UP to access the user and assigns an IP address. The corresponding service traffic path is CDN-CR-UP-pool end MER-MCR-MER-OLT-user.

[0027] For the IPTV multicast service bearing process, during dial-up authentication, the dhcp discover message is broadcast to all UPs at the pool end. The UP encapsulates the message into a VxLAN tunnel and sends it to the CP. The CP authenticates with the AAA according to the option field in the message. After successful authentication, the CP assigns an address (or requests an address from the DHCP server as a dhcp relay). The CP selects a suitable UP, and subsequent dhcpoffer / request / ack are all unicast; the CP issues a forwarding flow table; the CP requests the AAA to start the charging process. The corresponding service traffic path is multicast source-CR-intelligent metropolitan area network-OLT-ONU-IPTV set-top box.

[0028] For the voice service bearer process, during dial-up authentication, the ONU starts the IPoE process, broadcasts the DHCP Discover message to all UPs at the pool end. The UPs encapsulate the message into a VxLAN tunnel and send it to the CP for adjudication. The CP assigns an address, selects a suitable UP to undertake the service for this ONU, unicasts a DHCP offer to the ONU, and subsequent request / ack messages are all sent unicast. The CP issues a forwarding flow table to the UP, and the UP converts the received flow table into a local forwarding entry. The corresponding service traffic path is user-OLT-MER-MCR-MER at the pool end-UP-CR-ASBR-bearer network-SBC.

[0029] For the home gateway management service bearer process, during dial-up authentication, the DHCP Discover message is broadcast to all UPs at the pool end. The UPs encapsulate the message into a VxLAN tunnel and send it to the CP for adjudication. The CP assigns an address, selects a suitable UP to undertake the service for this ONU, unicasts a DHCP offer to the ONU, and subsequent request / ack messages are all sent unicast. The CP issues a forwarding flow table to the UP, and the UP converts the received flow table into a local forwarding entry. The corresponding service traffic path is user-OLT-MER-MCR-MER at the pool end-UP-CR-ASBR-bearer network-RMS server.

[0030] For the Internet dedicated line service bearer process, the Internet dedicated line authentication process uses the IPOE method for access (public network IP static address allocation). During authentication, the IP address of the user device is statically configured, and a UP is manually specified to undertake the bearer for this user. The user device sends an ARP request message to the specified UP, and the UP sends a reply message to the user device. The corresponding service traffic path is user-OLT-MER-MCR-MER at the pool end-UP-CR.

[0031] The present invention deploys the control plane CP of the broadband core network centrally by province, with 1+1 hot standby deployment at different addresses or locations. Real-time synchronization of user data is carried out between the two CPs. When one CP fails, the other CP can smoothly take over all UPs, and users do not need to redial. When a whole UP fails, the number of users on this UP will be evenly distributed to the remaining UPs to achieve user load sharing.

[0032] Finally, the present invention deploys the control plane CP of the broadband core network in the core computer room, and realizes the connection with the transmission through fiber optic jumpers, which is conducive to network management and network layer division. The user plane UP of the broadband core network is for service forwarding and is located at the same network position as the traditional metropolitan area network BRAS. In addition, it is located in the same computer room as the OLT to be cut over, which is convenient for fiber optic jumping and cutover operations. The deployment location can also be the same as that of the traditional metropolitan area network BRAS to meet the requirement of separation between CP and UP.

[0033] Compared with the traditional metropolitan area network BRAS (Broadband Remote Access Server), the weak computing and storage capabilities of the main control board of a single traditional BRAS device limit the user specifications of the forwarding plane physical devices. After the control function is centralized and cloud-managed, the number of users supported under the same hardware conditions has increased significantly. The more efficient resource utilization of the forwarding plane has reduced the expansion requirements and improved the resource utilization rate.

[0034] Compared with the situation in the existing network BRAS where the IP address pool is pre-planned, there are prediction errors and dynamic changes in the number of users, resulting in insufficient IP addresses for some devices and new users being unable to go online, while some devices have surplus IP addresses that cannot be shared with other devices and are wasted. In the present invention, the CP centrally controls the IP addresses, applies and allocates them on demand, and can automatically release them after use, enabling efficient use and simplified operation and maintenance management.

[0035] In addition, each traditional distributed BRAS (Broadband Remote Access Server) device needs to be configured on-site. For example, for 100 devices with 800 command lines per device, the total number of configuration command lines will reach 80,000. With BNC, through centralized management, global services are uniformly configured on the CP. Changes to basic Radius attributes and QoS configuration templates are also completed in the CP configuration and then distributed to all UP devices. The total number of configuration command lines = CP configuration + (channel configuration + interface configuration) × number of devices = 800 + (30 + 26) × 100 = 6,400, and the reduction in the configuration workload is as high as 90%.

[0036] The traditional BRAS has a mesh logical connection with the service system, and the upgrade and cutover of the service system are relatively cumbersome. In the BNC architecture of the present invention, only the CP is docked with the service system, and the logical structure with the service system presents a single connection, simplifying the service system docking; the processing speed of user online messages and control messages will be significantly improved, effectively avoiding the avalanche effect under the pressure of a large number of users.

[0037] Summarizing and analyzing the requirements for BRAS (Broadband Remote Access Server), more than 60% of the new requirements are mainly for modifying Radius attributes, QoS template sales menus, etc. in the control plane. The control plane of the traditional method also needs to be uniformly upgraded. For operators with more than a hundred devices, the upgrade time will last for several months or even one year. Under the BNC architecture of the present invention, basic configurations of forwarding plane devices are added to the UP, and at the same time, the software functions of the CP can be independently upgraded, greatly improving the efficiency.

[0038] In the broadband core network deployment method based on separation of control and forwarding according to the present invention, the control plane of the broadband core network configures corresponding hardware and software facilities according to the planned number of users to be carried. The user plane of the broadband core network calculates the corresponding resource requirements based on the concurrent online rate and the planned number of users to be carried, and configures as required.

Claims

1. A deployment method for a broadband core network based on separation of control and forwarding, characterized in that, The broadband core network control plane is centrally deployed by province, with 1+1 hot standby deployment at different sites or in different locations; the broadband core network user plane is centrally deployed by city, with 3+1 warm standby deployment at different locations; the broadband core network control planes are interconnected through MER equipment, using L3VPN bearer, and using MER to access the intelligent metropolitan area network and communicate with CR equipment; the broadband core network user plane is dually connected to two CRs at different locations, included in the metropolitan area network autonomous domain management, and connected to the broadband core network control plane through the intelligent metropolitan area network, and connected to the OLT equipment downstream.

2. The broadband core network deployment method based on separation of control and forwarding according to claim 1, characterized in that: When the OLT device is connected to the user plane of the broadband core network through the convergence device, the user plane of the broadband core network is centrally deployed in cities and counties, and 1+1 warm standby is adopted.

3. The broadband core network deployment method based on separation of control and forwarding according to claim 2, wherein: The OLT device is connected to the broadband core network user plane through a layer 2 aggregation device, and performs service distribution and port aggregation on the OLT through a layer 2 transparent transmission method.

4. A method for deploying a broadband core network based on separation of control and forwarding according to claim 1, characterized in that: The broadband core network control plane communicates with the external server via the public network plane through Native IP.

5. A method for deploying a broadband core network based on separation of control and forwarding according to claim 1, characterized in that: The OLT device is connected to the intelligent metropolitan area network in QinQ mode, and EVPN VPLS is deployed between the MER in the aggregation area and the MER on the user plane of the broadband core network, and the outer VLAN of the OLT message is matched to introduce the traffic into the EVPN VPLS instance.

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