ADTRAN Express 6530 6530 Installation And Maintenance Manual

Also see for Express 6530: Job aid

Contents

61225001L1-5D 17The NTU provides framing on the E1 port asdescribed in G.704 (sections 2.3 and 5) and G.706(section 4) and G.736. In this mode, the data arrivingat the SHDSL interface need not contain any G.704framing and the NTU generates the framing. One ormore services can be routed into time slots 1-31.CRC-4 multiframe may be enabled or disabled. Thedefault is disabled. The NTU routes one or moreservices from the SHDSL payload into time slots1-31, as well as routing time slot 0. In this modeG.704 framing is present in the data arriving on theSHDSL interface, and this is passed transparently tothe G.703 interface.NOTENot all time slots are necessarily routed betweenthe SHDSL and G.703 interface – some may berouted from the SHDSL to the Nx64K interface.See the CRC-4 Multiframe subsection.The NTU monitors the G.704 framing to detect errors(and thus drive the NTU LEDs) and to determine thevalue of the TS0 spare bits. The NTU transfers allSHDSL payload time slots transparently through theG.703 port without framing or monitoring. In thismode the port operates as a 2 Mbit/s G.703 interfacewithout any G.704 framing. This implies that thewhole SHDSL payload comprises a single service.The following alarm conditions can be monitored onthe G.703/G.704 interface (if applicable to the currentconfiguration):1. AIS (Alarm Indication Signal)2. BER (Excessive Bit Error Rate)3. LOMFA (Loss of Multi-Frame Alignment)4. LOF (Loss of Frame)5. LOS (Loss of Signal)6. RAI (Remote Alarm Indication)7. SlipWhen the NTU is configured for an unframed servicethe only alarm available is LOS. Consequentialactions can only be undertaken if G.704 framing iseither delivered by the remote unit or is beinggenerated on the NTU. If framing is being generatedby the LT then the LT is responsible for these actions.While any of the alarm states LOS, AIS, LOF,LOMFA and BER are detected, the followingconsequential actions will occur:1. The remote alarm indication (bit 3 of the TS0B- word) will be set as described in the G.704,G.726 and G.706;2. The G.703/G.704 alarm LED will be on,3. AIS will be transmitted toward the network in allcorresponding data time slots.NOTERAI assertion by the NTU can be disabled (thedefault state) under the G.703 Options Screen bythe Customer RAI generation option.When remote alarm indication is detected, the alarmcondition will be displayed on the front panel.

/ 20

Related manuals for ADTRAN Express 6530