Design And Implementation Of The IP Board Card In Three-Stage Hybrid Reconfigurable Switch

With the widely use of communication satellite,the demand of capacity and quality of the satellite communication is higher and higher.The switch this paper refers to combines three technologies,three-stage clos switch and hybrid switch and reconfigurable technology.Three-stage clos switch supply the switch on satellite with large capacity switch network.Hybrid switch technology provides packet switch and circuit switch on one switch level,which could guarantee the service of bandwidth and delay and supply flexible dynamic bandwidth service.And the reconfigurable technology offer high flexibility for connection service.In the three-stage hybrid reconfigurable switch system,IP board card achieves the function of service convergence and cell format adaption and transfers the cell through board bus to the input stage of the core switch network.Cell cache function exists in the input stage,and scheduling will be operated according to the service.For circuit service,fixed delay and path will be allocated by the three stages,and for packet service,middle stage arbitrates some disputes caused by input stage and sends the link result back to input stage.When input stage gets the result,dequeue and sending of the cell stored in the buffer ram will be operated.Output stage sent the circuit service cell according to the fixed time slot to the IP board card just like the input stage.When packet service cells are received,these will be queuing in buffer ram and then sent to IP board card to finish the switch process.The functions of the IP board card presented in this paper are:(1)translating the two network service into fixed length cell.(2)converging the service into 1 Gbps high-speed service flow.(3)distributing the bandwidth by controlling the quantity of the network service into the core switch network.