ABB FOX61 Series User Manual

Contents

ABB FOX61 Series User Manual Manual pdf 21 page image

F U N C T I O N A L D E S C R I P T I O NFOX61xLEDE1 215.2 ProtectionLEDE1 supports 1+1 subnetwork connection protection (SNCP) for P12 andP0-nc signals.P12 and P0-nc protection switching for signals from the network or aggre-gate side takes place on a tributary unit, e.g. LEDE1. A P12 or P0-nc signaltransported over the network is received e.g. on one or two SAMO1 units asa working and a protecting signal. The signal state of the working and pro-tecting signal is brought via the PBUS to the LEDE1 unit. The LEDE1 unitperforms the selection according to the signal states of the two signals.Figure 6: P12 SNCP with two SAMO1 units1+1 SNCP provides the following functions:• The LEDE1 unit selects the received signal from one of the two P12 orP0-nc signals and switches to the other P12 or P0-nc if this signal fails.• The operation type can be revertive or non-revertive (future release).• The switching type can be unidirectional or bidirectional.The unidirectional protection switching uses no protocol. The bidirectionalprotection switching uses the remote defect indication (RDI) as switchingcriterion. This provides bidirectional protection switching also when onlyone direction of a bidirectional connection fails.The bidirectional switching type is only available for ports that are config-ured for one of the terminated transport modes.• There is no restriction about the selection of working and protecting P12or P0-nc.P12 and P0-nc protection switching takes place in the P12/P0-nc cross con-nect function of the PBUS access circuit.Protection switching action can be driven by two different request types:• Traffic signal requests:− Signal fail (SF).P-12VC-12C-12P12E1P-12VC-12C-12LEDE1SAMO1SAMO1PBUS