RAD Data comm ASMI-450 operation manual Hdsl Signal Structure HDSL-Related System Functions

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Introduction

HDSL Signal

Structure

HDSL-Related System Functions

By reducing the line symbol rate, the maximum range that can be reached is increased. This is achieved by offering several versions of ASMi-450, each operating up to a given maximum rate. Together with the advanced digital signal processing techniques implemented in HDSL systems, this results in a robust data transmission system that can reliably operate over regular unconditioned local loops.

The HDSL signal is organized in frames. The HDSL frames carry user data, framing and synchronization data, and overhead data. The overhead data is used for a supervision and management channel, called embedded operations channel (EOC) that serves for status transfer, diagnostic loopbacks and tests, etc.

The HDSL subsystem performs the following main functions:

∙Mapping of input data bits into frames.

∙Start-up process.

∙Frame alignment.

∙System management by means of the EOC channel.

To achieve proper operation, one of the unit<F14P11>s serves as the master that controls the system start-up procedure, provides the timing reference for HDSL loop transmission, and manages the communication on the EOC channel. The master unit is called line termination unit (LTU) and is located at the central office side of the link; the other unit is called network termination unit (NTU) and is located at the remote end of the link.

The transmission of data on the HDSL loop is full duplex. To enable duplex transmission, HDSL transceivers use an echo canceller, based on advanced digital signal processing (DSP) techniques. When starting system operation, the echo canceller is “trained”, to enable the separation of the received signal from the transmit signal. The training is performed by transmitting a special sequence for a predetermined period. This process is called “start-up process”; data transmission can start only after its successful completion.

ASMi-450 Installation and Operation Manual

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Contents ASMi-450 Warranty Hdsl SelvRegulatory Information Declaration of Conformity Page Contents ASMi-450 Control from the Control Port Appendix a Connector Wiring Contents List of Figures List of Figures Xii List of Tables List of Tables Xiv Preliminary Preparations Starting Procedure Starting the ConfigurationConfiguration Procedure Step Action Use the CommandFunction Terminal Type TV920 VT52 VT100 Freedom 100/110 Type Configuration Display Commands Control Commands Command IndexQuick-Start Guide Functional Description Purpose and Main FeaturesTypical Application for ASMi-450 with Data Interface Hdsl Subsystem Characteristics Internal timing System TimingControl ASMi-450 Operation Local ControlRemote Management Introduction Power Requirements Test and Diagnostics CapabilitiesAlarms Physical CharacteristicsTransmission Media Hdsl Line Signal Binary Digits Quaternary SymbolOperating Environment Hdsl Signal Structure HDSL-Related System Functions Hdsl Interface Technical SpecificationsEthernet Interface Physical Characteristics General Chapter InstallationSite Requirements UnpackingASMi-450 Configuration Information GeneralOpening ASMi-450 Case Switch S1 Jumper and Switch Location FunctionsASMi-450 Internal Settings OFF Internal Settings Procedure Reinstalling ASMi-450 Cover Jumper R/CJumper FGND/GND Connector Location Grounding Power Connection Users Port Connections AC Power ConnectionDC Power Connection Hdsl Line Connections Control Port Connection Scope Chapter Front-Panel Operating InstructionsControl or Indicator Function Front Panel Controls, Connectors, and IndicatorsIndicators Indicator FunctionEthernet Interface General General Operating Instructions Display Functions Control of ASMi-450 Operation, GeneralDisplay Description See Configuration ParametersStatus Messages Test FunctionsPush-buttons Using Front-PanelOrganization ASMi-450 DisplayFront-Panel Operating Instructions Designation Function Values System Configuration ParametersControl Port Configuration Parameters Operating Instructions Turn-on Checking Current Operating ConfigurationDisplay CursorScroll Ethernet Interface Indications Fault IndicationsStep Action Key Display Normal Front-Panel IndicationsProtection Local Configuration Set-Up ProcedurePassword Configuration ProcedureAlready there Scroll to display the desired group Alarm Buffer Specific Configuration GuidelinesSP Parameters LCD Configuration Error Messages Front-Panel Operating Instructions Chapter ASMi-450 Control from the Control Port Hardware Requirements Clear to Send CTS Interface TypeData Terminal Ready DTR Request to Send RTSAutobaud Function Ring Indication RIData Set Ready DSR ASMi-450 Preparations Supervision Terminal Connections Internal SettingsControl Port Configuration Preparation for Use of Supervision TerminalOption Meaning Example of Usage Command Language Syntax Command OptionsCommand Protocol ASMi-450 Supervision LanguageIndex of Commands Command Purpose Options Format ASMi-450 Command Set DescriptionCLR ALM CLR LoopCLR TST DateDEF Agent Display Fields DEF NameDEF PWD DEF NodePurpose Format Use DEF SPPWD DEF Term DEF SYSDSP ALM Function Terminal Type VT-52 VT-100 Freedom-110Format Use Alarm No Alarm Syntax Meaning State Time Remote DB Remote AlarmRemote Signal Loss Quality AlarmConnected DSP HDR TSTDSP ST Line REM LAN notDSP ST Port Display FormatPurpose Format Use Display Format Exit DSP ST SYSHelp Init DB Parameter Designation Default ValuePassword LoopNode Time ResetStarting a Session Single ASMi-450 Control Session Ending a Control Session Configuration Error Messages ASMi-450 Control from the Control Port Status Indications and Messages Indicators DisplayON/OFF Message Description Corrective Actions AlarmASMi-450 Alarm Buffer Messages Cont’d Remote Alarm Remote Reverse Test Functions Test FunctionsOperating Instructions Loop REM REM PortActivating the Test Functions from a Control Terminal Power-Up Self-TestTrouble Symptoms Probable Cause Corrective Measures Troubleshooting InstructionsLAN Pin Designation Direction Function RS-530 DCE Connector and Adapter CablesPin Designation Direction Function 36/RS-449/422 RceaRceb V.35 DCE Connector X.21 DCE Connector Pin Line Connected Connected to To Terminal Hdsl Line ConnectorRS-232 V.24 Control Port Connector Pin FunctionEthernet Interface Connector Appendix B Snmp Management Snmp Environment General Snmp PrinciplesSnmp Operations Management Information Base MIB StructureMIBs Supported by the ASMi-450 Snmp Agent Access Restriction Using Snmp Communities Management Domains UnderSnmp Communities Read ASMi-450 CommunitiesAddress Class First Byte Address Range IP EnvironmentGeneral IP Environment IP Address StructureSnmp Management Snmp Traps Appendix C Installation in 19 Racks Figure C-1. Installation of Single Unit in 19 Rack Installation of Single UnitGeneral Preparations Installation of Two UnitsFastening the Two Units ASMi-450 To install the ferrite cores