Page 1 of 6 Title Demonstrate knowledge of telecommunications bearer and switching systems Level 4 Credits 20 Purpose This unit standard covers underpinning knowledge for people engaged in installation and maintenance of telecommunications bearer and switching systems. People credited with this unit standard are able to demonstrate knowledge of: the telecommunications OSI model; digital multiplexing; digital switches and networks; telecommunications bearer systems; telecommunications transmission and switching installation and testing practices; the fundamentals of a broadcast control system, and a coaxial or fibre cable communication system for provision of customer services; data fundamentals relevant to business services; plans and specifications used in the installation of telecommunications bearer and switching systems; and retrofitting telecommunications bearer and switch installations. Classification Telecommunications > Telecommunications - Service Delivery Available grade Achieved Guidance Information 1 References Electricity Act 1992; Electricity Safety Regulations 2010; Telecommunications Act 2001; and its subsequent amendments and replacements. 2 Definitions BER bit error rate. BNC bayonet navy connector. Cable any or all of copper cable, fibre optic cable, coaxial cable. Industry practice those practices, which competent practitioners within the industry recognise as current industry best practice. LAN local area network. MUX multiplexing equipment. OSI the open system interconnection model.
Page 2 of 6 OTDR optical time division reflectometry. PABX private automatic branch exchange. PCM pulse code modulation systems. PDH plesiochronous digital hierarchy. PMUX physical multiplexing equipment. ROM read only memory. SDH synchronous digital hierarchy. SkipMUX skip multiplexing equipment. STP shielded twisted pair cable. TDR time domain reflectometry. UTP unshielded twisted pair cable. VMUX virtual multiplexing equipment. 3 The phrase in accordance with industry practice is implicit in all performance criteria in this unit standard. Outcomes and performance criteria Outcome 1 Demonstrate knowledge of the telecommunications OSI model. 1.1 The seven layers of the OSI model are defined in terms of their attributes. physical, data link, network, transport, session, presentation, application. 1.2 Typical examples of applications and types of transmission media are outlined for the seven layers of the OSI model. Outcome 2 Demonstrate knowledge of digital multiplexing. 2.1 The operating principles of a digital multiplexing system are described with reference to major components and signal waveforms. analogue-digital conversion, Nyquist Sampling Theorem, time division multiplexing, demultiplexing, digital-analogue conversion, synchronisation, analogue interfaces. 2.2 The effects of sampling and transmission errors on speech are described, and acceptable bit error rate for end-to-end transmission is stated.
Page 3 of 6 2.3 The fundamentals of different types of digital multiplexing systems are described in terms of operation and applications. PMUX, VMUX, SkipMUX, drop and insert MUX. 2.4 SDH and PDH hierarchies are described in terms of operation and applications. Outcome 3 Demonstrate knowledge of digital switches and networks. 3.1 The operation of a typical electronic switch is described with reference to a block diagram indicating all major functional elements including support services. switch PABX, public network exchange; support services power supplies, alarm telemetry and control. 3.2 The effects of jitter and slipping on the operation of the switch are explained. 3.3 The major functions of a subscriber line interface are explained. battery feed, ringing, supervision, hybrid, balance network, amplification, level adjustment. 3.4 The hierarchy of switches from local exchange to international exchange and how synchronisation is maintained are described. 3.5 The concepts of diversity through self-healing rings and hitless switching are explained in the context of network architecture. 3.6 A typical fault and alarm system is described with reference to operation and facilities provided. Outcome 4 Demonstrate knowledge of telecommunications bearer systems. bearer systems PCM, fibre optic, coaxial cable, microwave. 4.1 The operation of bearer systems is described with reference to block diagrams showing all major elements, interfaces, and support services. support services power supplies, alarm telemetry and control. 4.2 Interfaces between major elements are described with reference to waveforms, bit rate, and power feeding where applicable.
Page 4 of 6 4.3 Common impairments to the quality of transmission are described with reference to causes and system design factors to minimise them. 4.4 A typical fault and alarm telemetry system is described with reference to operation and facilities provided. Outcome 5 Demonstrate knowledge of telecommunications transmission and switching installation and testing practices. 5.1 The principles of earthing and shielding for safety, and for minimisation of noise and interference are described in accordance with industry practice. 5.2 Safety practices relating to fibre optic cable and connectors are described. 5.3 Installation requirements for location, space, and support services for a small equipment installation are described in accordance with industry practice. 5.4 Common transmission level and impairment measurements are described, and appropriate instruments identified. bit error rate (BER), loss versus frequency, psophometric noise, attenuation, crosstalk, time division reflectometry (TDR), optical time domain reflectometry (OTDR), clocking and synchronisation jitter and slipping. 5.5 Commonly used connectors are identified, and cable terminations are made according to industry standards. connectors UTP, STP, coaxial, BNC, optical fibre. 5.6 Terminating facilities are described with reference to connector types and installation practice. structure and location of cabinets, closets, frames. Outcome 6 Demonstrate knowledge of the fundamentals of a broadcast control system, and a coaxial or fibre cable communication system for provision of customer services. 6.1 A typical control system for commercial radio programmes is described with reference to major components, their functions, and waveforms at the interfaces.
Page 5 of 6 6.2 A typical coaxial or fibre cable communication system for provision of customer services is described with reference to major components, their functions, and waveforms at the interfaces. Outcome 7 Demonstrate knowledge of data fundamentals relevant to business services. 7.1 Data network infrastructures are described in terms of components, interfaces, and transmission media. components terminators, connectors, boot ROMs, hubs, repeaters, servers, workstations; interfaces connectors, internet protocols; media cables, wireless. 7.2 LANs are described in terms of their objectives and benefits. typical objectives simplicity, reliability, transparency, manageability; typical benefits shared resources, incremental growth, security. Outcome 8 Demonstrate knowledge of plans and specifications used in the installation of telecommunications bearer and switching systems. 8.1 A typical set of plans is interpreted. correct identification from the plans of type, location, and interconnections of frames, cabinets and other equipment racks, cables, cable trays, terminating boxes. 8.2 A typical specification is interpreted. all practical installation requirements are identified. Outcome 9 Demonstrate knowledge of retrofitting telecommunications bearer and switch installations. 9.1 The elements for planning a retrofit installation that will integrate with existing switching and transmission equipment infrastructures are outlined. typical elements scope of work, site survey, locating cables, verification of existing infrastructure and documentation.
Page 6 of 6 9.2 Factors influencing re-use or replacement of existing equipment are outlined. 9.3 Methods for the recovery and disposal of existing switching and transmission equipment, and cabling are outlined. Planned review date 31 December 2020 Status information and last date for assessment for superseded versions Process Version Date Last Date for Assessment Registration 1 20 September 2002 N/A Rollover and Revision Rollover and Revision 2 25 February 2008 N/A 3 23 November 2017 N/A Consent and Moderation Requirements (CMR) reference 0101 This CMR can be accessed at http://www.nzqa.govt.nz/framework/search/index.do. Comments on this unit standard Please contact Infrastructure ITO qualifications@connexis.org.nz if you wish to suggest changes to the content of this unit standard.