OSN3500 EFS0A Single Board Introduction

OSN3500 EFS0A single board consists of Ethernet Access Module, Network Processing Module, Mapping Module, Interface Conversion Module, Logic Control Module, Clock Module and Power Supply Module, and the specific functions of each module are shown below:

OSN3500 EFS0A Single Board Ethernet Access Module In the receiving direction, the Ethernet access module converts the optical signals sent from Ethernet devices such as switches or routers into electrical signals. If the signal is accessed from an electrical interface, no optical conversion is required. At thePHYlayer, the Ethernet access module performs decoding operations on the electrical signal and detectsthe ETH_LOSalarm signal. The Ethernet access module then performs serial-to-parallel conversion of the electrical signal and sends the converted signal to the network processing module. In the transmit direction, the Ethernet access module performs the parallel-to-serial conversion operation andencodes the signal and performs the electro-optical conversion operation at thePHYlayer.

The OSN3500 EFS0A single board network processing module consists of a network processor and a switching network. The network processor first performsMACfunctions, including code conversion, Ethernet packet framing,CRCchecksum and Ethernet performance statistics. Once the Ethernet frames, which have undergone the stripping operation, have entered the core of the network processor, the data streams are categorized according to service type and configuration requirements. The frames are then encapsulated or decapsulated. The network processing module supports the following encapsulation formats:MPLS,L2 MPLS VPN, and Ethernet/VLANIn the receive direction, the network processing moduleperforms mapping and forwarding operations for services withTunnelandVCidentifiersbased on the service configuration.In the sending direction, the network processing moduleextractsthe TunnelorVCidentifiers according to the level (PorPE)of the device. Then, the service is distributed or forwarded.

The OSN3500 EFS0A single-board network processing module supports the following functions: flow detection and flow classification, unicast, multicast, and broadcast for flows, data priority setting, weighted fair queuing, and four levels of service hierarchy .

OSN3500 EFS0A Single Board Mapping Module: The mapping module completes the encapsulation and mapping functions. In the uplink direction, the mapping module first encapsulates Ethernet signals intoLAPSorGFPformat and cascades them. Then, the mapping module converts the Ethernet signals intoSDHsignals. In the downlink direction, the mapping module demapsthe SDHsignals and compensates for the virtual cascade delay. Through the alignment operation, the mapping module decapsulates the packets according to the encapsulation format. The decapsulated data is finally sent to the network processing module.

The OSN3500 EFS0A single-board interface conversion module convertsthe622M LVDSbus of theSDHsystemto a parallel bus. The high-speed backplane interface is connected to the system's low-speed interface chip through the interface conversion module.

The OSN3500 EFS0A single-board logic control module consists of aCPU, registers, oscillator, Ethernet port, andHDLCcontroller. The Logic Control Module is connected to external circuits via a bus and accomplishes the following functions: managing and configuring other modules on this board; and inter-board communication via the internal Ethernet interface.

The control module also contains the basic logic units. The control module performs the following functions: reads and writes registers, providesan interface to the CPU, detects and selects the clock, performs phase identification and frequency division operations on the clock, checks the presence status of the cross-over boards, the main control board, and the circuit boards, controls the shutdown operations of the optical modules, performs communication functions, and controls the indicator lights.

The EFS0A single-board clock module tracks the system reference clock and generates the working clock required by each chip. The clock frequency can be50 MHz,77 MHz,125 MHz, or155 MHz.The power supply module is mainly responsible for convertingthe-48V/-60Vpower supplyfrom theinput HuaweiSDHequipmentto the DC voltage required by all modules of the single board. You can refer to the information HuaweiOSN3500equipmentEFSOsingle board.