Key Telephone Systems

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Key Telephone Systems
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Key Telephone Systems

• Objectives for Chapter Ten
• Explain where key telephone systems (KTS) may be
  used
• Discuss the differences between the key telephone
  systems and PBX
• Describe the components that comprise the KTS
• Explain why the movement to an IP telephone set
  has occurred

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Key Telephone Systems

• Key telephone system
• Another form of resource-sharing device
• Used to reduce number of outside telephone lines
• Provide access to many users
• 1,648 equates to 16 outside lines, 48 tel sets

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Key Telephone System Components

• Key service unit heart brain of system
• Line cards interface to CO lines
• Station cards control intelligence, interface to
  end users KTS, to line cards for access control
• Intercom cards optional
• Telephone sets single-or multiple-lines
• Power supplies, logic cards
• Wiring infrastructure

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Key Telephone Systems Wiring

• Infrastructure
• RJ-21x (telco block)
• RJ-11
• 66 block (vendor block)
• Horizontal run
• Four-pair
  cabling

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Key Telephone Systems Compared to PBX

• KTS is computer-stored, programmed-controlled
• Similar to PBX
• Large as 200 ports
• PBX small as 50 ports
• Basic market position
• Simple connections
• Rich in features
• Significant penetration into business community
• Departments use widely, behind PBX or Centrex
• Many try to emulate KTS with PBX functions
• Multiline sets
• Access to PBX features
• Clustering of workers via a key system

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Why Key Telephone Systems?

• Rationale for KTS
• Economies of scale lines to CO vs. stations
• Monthly savings vs. CO lines
• Cost of telephone system, factors
• Voice mail
• SMDR
• Automated attendant
• Least-cost routing
• Data, voice simultaneously
• ACD
• Wiring, installation
• Basic analog set vs. multiline sets
• Having a system or not?
• Maintenance
• Equipment
• Payout of straight line system vs. KTS
• Advantages beyond financial
• Intercom
• Easier to add features and services than for
  single-line

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Key Set Vendor Interfaces

• KTS Vendor interfaces
• Terminate lines in RJ-11C or RJ-21X
• 2500 set
• Battery backup

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IP Telephones

• Innovations in the KTS
• Migrating from data-oriented Internet to real-
  time voice over the Internet
• Cisco phone
• Default config msgs., conf, forward, speed 1,
  speed 2, redial, call park, call pick-up, night
  service

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IP Telephony

• GUI Interface
• IP Gateways
• Bridge circuit-switched
• Traditional telephony
• Packet world

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Vendor Proposal

• Purchase of key telephone system
• Know benefits features
• Capacity for growth before major upgrade required
• Never believe the best deal is on the table on
  the first proposal
• Preparation for purchasing key or PBX
• Needs assessment
• What are buying motivations?
• Look for hidden needs user survey
• Document needs and motivation
• Issue RFI to gather info about players in your
  area
• Use RFI to prequalify bidders
• Determine future needs., ie., system,
  growthdevelop RFP
• Budgetary approval in advance
• Release RFP, formulate target date
• Analyze bids, make short list of bidders
• Negotiate contract, firmly
• Allocate plenty of time for whole process
• Avoid paralysis by analysis (taking too long)

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Key Telephone Systems

• Notes