SDH/MSTP and PTN network docking guidance I. Scope of application This guideline applies to synchronous digital series / multi-service transport platform (hereinafter referred to as SDH/MSTP) and packet transport network (hereinafter referred to as PTN) network docking scenarios, PTN network bearer circuits and the existing SDH/MSTP network interoperability when the solution, the configuration principles, etc. are explained. Second, SDH/MSTP and PTN network docking guiding principles (a) Transmission network architecture Guangdong Mobile local transmission network SDH/MSTP/PTN equipment system layer is mainly backbone layer, convergence layer, access layer three-layer structure, the backbone layer is mainly to provide relay circuits between the core network elements, to complete the connection with the upper trunk and interconnection and interoperability with other operators' networks; the convergence layer consists of an important business with the status of the convergence node, responsible for the interoperability of PTN network bearer circuit and the existing SDH/MSTP network solutions. The convergence layer is composed of convergence nodes with important business status, responsible for business convergence and channeling in a certain area; the access layer is mostly composed of access nodes such as mobile communication base stations, IP access points and customer access terminals, which connect circuits to the convergence layer in the vicinity. (B) cross-network docking SDH/MSTP and PTN cross-network docking is mainly for the existing network architecture, across the SDH, PTN network backbone layer, convergence layer, access layer network docking, at this stage to achieve the purpose of PTN network access, SDH network terminals are mainly (the 2G network, for example: the existing BSC ports are connected to the SDH network, the PTN access to the 2G base station needs to be). According to the different configurations of network docking interface and protection, it can be mainly divided into two ways of network-side and user-side docking. 1. Network-side docking: the service circuit is not terminated at the SDH/PTN network docking interface (not landed), and cross-network docking is realized in the way of pass-through, and the docking of the PTN and SDH network side includes the tunnel mode, the tunnel mode, the tunnel mode, the tunnel mode, the tunnel mode, the tunnel mode, the tunnel mode, the tunnel mode, and the tunnel mode. The PTN and SDH network side docking includes "tunneling mode", "gateway mode" and other ways of docking. Network side docking in the convergence node and the core node for docking, to facilitate the integration and processing of services. This method can realize end-to-end management and configuration of circuits, and can realize end-to-end circuit double node, double route security protection, the disadvantage is the relatively large occupation of SDH network resources. 2, user-side docking: service circuits in the SDH/PTN network docking interface to the end (landing), in the ODF/DDF to achieve cross-network docking; this way of circuit configuration is flexible, less resources occupied by the existing network, in the various layers of the circuit within the dual-route protection can be achieved, the disadvantage is that the circuit is layered configuration, can not be realized dual-node protection. (3) Network-side and user-side docking methods are used in different network scenarios, and the local municipal companies can select them according to the actual situation of their SDH/PTN networks and resource utilization. (iii) Network-side docking mode 1. "Tunneling mode": l Docking interface: PTN and MST network docking place P adopts GE and CSTM-1 for docking, and the MSTP service landing place carries out service termination conversion through PTN terminal equipment (to be added). l Service configuration: services are carried out in PTN terminal equipment (to be added). l Service configuration: services are carried out in PTN terminal equipment (to be added). l Service Configuration: The services are transparently transmitted within the PTN and SDH networks, and the MSTP services are landed at the MSTP service landing place through the terminal equipment. Create tunnels and pseudowires from P1 to P4. blue LSPs. create EOS services from S2 to S1 in the MSTP network to transparently carry the LSPs of the PTN. create CES E1 services from P1 to P4 to the C.STM-1 interface termination of the P4 node. Then connect this C.STM-1 to S1 and configure the time slot crossover to the service network element side. l Protection setup: the service end-to-end is protected by LSP 1:1: Create a tunnel and pseudo line from P1 to P4. such as the blue LSP. create a protection tunnel from P1 to P4. such as the red LSP. and create an LSP 1:1 protection group. Create EOS services from S2 to S1 in the MSTP network, transparently carrying the blue and red LSPs of the PTN, respectively. Create a CES E1 service from P1 to P4, terminating at the C.STM-1 interface of the P4 node. Then connect this C.STM-1 to S1. l Clock Configuration: The transmission of 2G services requires only frequency synchronization and can be realized by adopting the scheme of network-wide frequency synchronization (that is, clock synchronization). the PTN can obtain clocks from a variety of interfaces, and the details of the support are shown below Physical-layer Clock Frequency Synchronization Supported by the PTN: It can track the external clock source (2 Mbit/s, 2 MHz), line clock source (SDH line, synchronous Ethernet line), and tributary clock source (E1). Supports line clock output, branch clock output and external clock output. Supports non-SSM (Synchronization Status Message), standard SSM and extended SSM. This solution suggests that the PTN directly track the frequency of the SDH network to achieve network-wide clock synchronization. If time synchronization is required, since MSTP usually does not support 1588V2, it is recommended that time signals be introduced from the aggregation layer and the PTN network complete its own 1588V2 synchronization. l Management Solution If PTN and MSTP can adopt unified network management, PTN and MSTP are managed and maintained on the same network management; if PTN and MSTP cannot realize unified network management, then consider adopting sub-network management. 2. "Gateway mode": PTN and SDH are connected through C,STM-1/STM-44 network management mode. PTN transmits alarm, SD (performance degradation triggering protection inversion) and DCN information to PW and VC12 through the single board of gateway, so as to realize the interoperability of PTN and MSTP networks. In the case of this method of connection, the MSTP and PTN networks carry out service scheduling through a unified end-to-end. When the PTN network fails, the alarm is transmitted to the MSTP network through the PW in the gateway board, and the SNCP inversion is realized in the NodeB node; when the MSTP fails, the alarm is transmitted to the PTN network through the VC12 in the gateway board, and the PW inversion is realized in the RNC node, thus realizing the complete network inversion operation. This method has not yet been launched by the equipment manufacturers of commercial chassis, the relevant configuration principles to be related to the launch of the product, the provincial company unified organization of the test is issued. (D) user-side docking SDH/PTN user-side docking through the end of the business landing way to docking, because its business has ended, so according to the actual needs of the flexibility to select the convergence layer, backbone layer, backbone scheduling layer, and other layers of the network for docking, specifically as follows: In the case of the user-side docking, the convergence room, the core building are not new PTN equipment, in the existing equipment, increase the port of the disk In the case of user-side docking, no new PTN equipment is added in the convergence equipment room and the core equipment building, and port racks are added to the existing equipment to realize the interconnection of PTN convergence (backbone) system equipment and SDH local equipment. In order to enhance the efficiency of network resource utilization, the user-side pairing should be based on the 155M optical port method.