Customer Premise Equipment and Application

Customer Premise Equipment and Application Chapter 5

Objectives • Discuss the purpose of customer premise equipment in a telecommunications network • Identify the significant components of a modern telephone • Discuss the varieties of station equipment • Explain how private switching systems integrate with both CPE and the PSTN • Describe how enhanced CPE services and applications work and how businesses benefit from using them Modified by: Brierley

Introduction to Customer Premise Equipment • Everything on the consumer’s side of the demarcation point is known as customer premise equipment (CPE), because it resides on the customer’s premises. • In telecommunications, a telephone and any connected parts are known as station equipment because in the business world, they are located at a person’s station, or desk. Modified by: Brierley

Inside a Modern Telephone Modified by: Brierley

Handset Modified by: Brierley

Local Loop Current Modified by: Brierley

Wiring Modified by: Brierley

Wiring • Tip - the wire that supplies the ground (or zero charge) from the central office’s battery to the telephone. • Ring - the wire that carries a negative charge (-48 V) from the central office’s battery to a telephone. In other words, the ring is the wire that carries signals. • Hybrid coil - introduced into telephone sets to separate the incoming transmit and receive signals into their own two-wire connections. Modified by: Brierley

Wiring Modified by: Brierley

Ringer • The device that sounds a bell or tone to indicate an incoming call. • Ringing tone/ringback - the tone created by the combined frequencies of 440 Hz and 480 Hz. • Distinctive ringing - a unique ringing sound or cadence for different types of calls. Modified by: Brierley

Dialer • Rotary dialing - a user chooses a number and turns a wheel from that number to the finger stop then releases the wheel. • Touch-tone dialers - operate by transmitting a combination of two frequencies each time a button is pressed. Pressing each button issues a different combination of frequencies. Modified by: Brierley

Dialer Modified by: Brierley

Station Protection Modified by: Brierley

Pay Telephones • Telephones provided for public use that require coin, collect, or credit card payment to complete calls. • COCOT (customer-owned coin-operated telephone) - the name commonly used in the telecommunications industry to refer to a pay phone. • Totalizer - determines what type of coin was deposited and relays the information to the switch through pulses of brief, dual-frequency tones. Modified by: Brierley

Pay Telephones Modified by: Brierley

Cordless Telephones • Telephones that can be used without a physical connection to a telephone set, but still rely on a stationary telephone, or base station, to connect to the PSTN. • The main drawback to cordless phones is the ease with which signals can be picked up by eavesdroppers. • Spread spectrum transmission - signals are separated and distributed over a wide range of frequencies. Modified by: Brierley

Cordless Telephones Modified by: Brierley

TTY and TDD • TTY (TeleTYpewriter) - a device invented by the Teletype Corporation that uses alphanumeric characters entered through a keyboard to communicate over a voice or data network. • TDD (Telecommunications Device for the Deaf) - a specially designed device that uses a TTY and a terminal or computer screen to help speech and hearing-impaired people communicate over the PSTN. • TDDs can use relay centers, or call centers with operators who translate the typed input for the nonhearing-impaired party and type responses for reception by the hearing-impaired party’s TDD. Modified by: Brierley

TTY and TDD Modified by: Brierley

Key Telephone Systems • A system that gives all telephone users within an organization centralized access to one of many incoming PSTN lines. • A KTS typically consists of a wall-mounted control console that connects to the organization’s internal phones and to the telephone company’s end office. • This console, called a key service unit (KSU), signals the telephone attendant about incoming calls, controls busy indicator lights on line buttons, and tracks call information, among other tasks. Modified by: Brierley

Key Telephone Systems Modified by: Brierley

Key Telephone Systems • Features of electronic KTSs include: • Call forwarding • Caller identification • Direct inward dialing • Do not disturb • Message waiting • Music on hold • Station restriction • Voice mail Modified by: Brierley

Private Branch Exchange (PBX) • A switch owned and operated by a business or other private organization that connects multiple telephone sets to one or more of the telephone company’s central offices. • Provides call setup and routing within an organization. • Whereas a KTS depends on a CO for dial tone, a PBX actually provides its connected telephones with dial tone. • A PBX can connect an organization to the PSTN through a trunk, a connection with significantly more bandwidth than a local loop which serves to directly connect switches. Modified by: Brierley

Private Branch Exchange (PBX) Modified by: Brierley

Components of a PBX • A PBX consists of four significant elements: • Station lines - the lines that connect individual telephone sets to the switch. • Central processor - the computer that oversees all PBX operations, including processing incoming calls, outgoing calls, call setup, routing, supervision, and data gathering • Switching module - The equipment that accomplishes call setup, routing, and supervision, just as a switch in a central office does. • Trunks - The lines that connect the switch to COs. Modified by: Brierley

Components of a PBX Modified by: Brierley

Features Offered by a PBX • Automatic call distribution (ACD) • Automated route selection (ARS) • Computer-telephony integration (CTI) • Power failure provisions • Station message detail recording (SMDR) • System management • Trunk queuing • Unified messaging • Wireless capabilities Modified by: Brierley

Centrex Systems • Centrex System - a switching system that provides features similar to those offered by a PBX. However, in a Centrex system, services are supplied from the LEC’s central office. • Prevents an organization from having to purchase and maintain its own switching equipment. • Business’s lines are separated from other PSTN lines at the LEC’s CO so that only the subscribing business can use them. Modified by: Brierley

Call Accounting • The process of collecting call information in a database format and making it available through a user interface, such as a software program. • For each outgoing call, a call accounting system can record: • Who initiated the call (from what extension) • The number and identification of the called party • How the call was dialed and routed • Whether the call was completed • How long it took to complete the call • Whether the call was local or long distance • How long the call lasted • How much the call cost Modified by: Brierley

Automatic Call Distribution (ACD) • A method of distributing incoming calls evenly over multiple stations, according to quantity of calls handled, free time, or availability. • Answers an incoming call, then analyzes information about the call. • ACDs can also generate information about calls, including how many were sent to a queue, how long the callers waited in the queue, and whether they hung up before the ACD could forward their call to an operator. Modified by: Brierley

Computer Telephony Integration • Significant call control functions that CTI enables, include: • Automatic dialing from a PC interface • Call screening based on incoming phone number identification • Call forwarding programmed through a simple PC interface • Automated attendant services • Call logging and the collection of call accounting data Modified by: Brierley

Computer Telephony Integration • Some of the significant media processing features that CTI enables include: • Voice message recording and playback • Fax storing and sending • Speech recognition and text-to-speech translation (for instance, your CTI-enabled computer could read an e-mail message to you) • Online call recording Modified by: Brierley

Computer Telephony Integration • Some of the customer data management features that CTI enables include: • Access to personal phone books saved on the network • Caller database records that appear when a number is selected from the phone book • Retrieval of customer calling patterns and billing information • Access to customer schedules Modified by: Brierley

Computer Telephony Integration Modified by: Brierley

Interactive Voice Response (IVR) • Enables individuals to provide and retrieve information to and from a computer through a touch-tone phone. • Saves money by allowing customers to help themselves rather than speak to a person and ask questions. • May provide information, accept information from a customer allow the customer to help direct his call through a series of options, or allow the caller to choose to speak with an operator. Modified by: Brierley

Voice Mail • Two categories of voice mail: • Standalone: may consist of a service supplied by a LEC’s CO or it may be a separate device, similar to an answering machine, connected to one or more station lines. • Integrated: one that is connected with a private switching system through a direct cable, similar to the way in which a CTI computer connects with a private switching system. Modified by: Brierley

Summary • Customer premise equipment includes telephones, modems, fax machines, answering machines, and so on. It may or may not be owned by the customer. • Touch tone, or simply tone, dialers operate by transmitting a combination of two frequencies each time a button is pressed. • In the telecommunications industry, a pay telephone is more commonly called a COCOT (customer-owned coin-operated telephone). Modified by: Brierley

Customer Premise Equipment and Application Chapter 5 END

Customer Premise Equipment and Application