9 - 1 - 1 System Lesson

The table below provides links to materials which are relevant and applicable across all of the courseware in this program. For ease of access, this table is reproduced on every page of each lesson.

Materials  Web Sites   Glossary   Bibliography   Formulas   Tables   Media   Resources   Maps   Documents   News   GIS   Careers

Lesson Outline Menu Module Description Duration Introduction 20 minutes The Public Switched Telephone System 30 minutes The 9-1-1 System 30 minutes The Cell Telephone System 30 minutes VOIP 30 minutes 911 Operation 30 minutes The Pitt Emergency Alert Notification System 30 minutes Total Module Duration 205 minutes

Introduction The emergency reporting system, commonly known as 9-1-1, is a standardized system for reporting emergencies over the telephone network. The requirements for an emergency reporting system include:

Easy to dial Available on all devices - telephones, computers, etc. Available everywhere Available on all systems - all vendors, all types (wireline, cellular, etc.) No charge Local service - connects to closest responders

The emergency reporting system originated in Great Britain as the 9-9-9 emergency telephone system established in 1937. The first US 9-1-1 system was set up in Haleyville, Alabama on February 16, 1968. Since that time systems have been implemented in most cities, counties or regions in the United States.

To guarantee ubiquitous access to emergency services, providers of public telephones (Pay Phones) were required to allow the 9-1-1 number to be dialed without inserting a coin. With the advent and popularity of the cell phone, pay telephones had almost become extinct. However, they have made a resurgence in cities with homeless areas. For example, a pay phone exists righr in the middle of the Hollywood "Walk of Fame" on Hollywood Boulevard.        Public Phone (Pay Phone)

9-1-1 Web Sites Government/Professional National Emergency Number Association (NENA) 9-1-1 Resource Center FCC 9-1-1 Allegheny County 9-1-1 Industry Council for Emergency Response Technologies (iCERT) NG 9-1-1 Institute Commercial 9-1-1 Magazine 9-1-1 Advisor Software TeleCommunications Systems Short Message Service (SMS) - text messaging FCC SMS

The Public Switched Telephone Network (PSTN) To understand how the 9-1-1 system operates, we must first know a little about how the telephone system operates. The provision of telephone service ansd the portfolio of services has changed dramatically in recent years and is still changing. We are going to take a simplified approach that is historical and focuses on wire providers, cellular providers and Internet providers. Historically the telephone network in the United States was a hierarchical network consisting of two types of companies: Local Exchange Companies (LECs) provided local service, sometimes called last mile service. Nationally there are about 1500 LECs. Verizon and Colsolidated Communications are examples in Pittsburgh. More recently cable companies such as Comcast have been permitted to provide local telephone service. Interexchange Carriers (IXCs) or long distance carriers provide communications between local exchange carriers. Sprint and AT&T are examples of IXCs. The diagram below shows the architecture of an LEC. Customers telephones are connected by wires called local loops to an end or central office. Business customers may have more sophisticated equipment, called Customer Premise Equipment (CPE), at their sites that provides the equivalent of an internal telephone network. Pitt has such equipment called a Private Braanch Exchange (PBX), located in Posvar Hall. An end office might host the equipment for one or more exchange. Telephone numbers are set and managed by the North American Number Plan Authority (NANPA). See www.nanpa.com. Our telephone numbers consist of three parts: NPA - the Area Code e.g. 412 or 724 for our area NXX - the Exchange e.g. 624 or 647 for Pitt XXXX - the Extension In urban areas if traffic warrants it, end offices are connected together by high capacity lines called trunks. In the original telephone system all of these connections were analog. Today, all trunks connecting telephone offices are digital. Most business and some commercial end users have digital local loops. In fact, Digital Subscriber Line (DSL) service is becoming very popular. In urban areas, the end offices are connected to an office called a Tandem End Office. Pittsburgh has two tandem end offices one in Oakland and one downtown. End offices are also connected to toll offices which connect the LEC to the IXC.

Telephone Central Office or End Office

When a customer (subscriber) picks up his or her telephone, a connection is signalled to the end office that serves that custoner. Equipment in the end office captures the number dialed. Each telephone office has one or more switches that routes the call based on the number captured. If the number is for a customer served by the same end office then the two customers are connected through the end office. When the number is for a different local end office, if the end offices are connected by a trunk, then the call is routed through the trunk. Otherwise, the call is routed through the tandem end office. Calls that are for subscribers within the region are routed through the toll office. Calls out of the area code are routed through the toll office to the IXC.

The diagram below shows the architecture for the Interexchange Carriers. These networks connect the local carriers. Calls that traverse these networks are long distance calls.

The Phone System in Emergencies

The local telephone system operates of of 48 volt direct current (DC) power. This system is completely independent of the electrical network. The phone lines are powered by banks of batteries in the central office. In some emergencies when electrical power has failed, the wireline phone system will still work. The phone company has emergency generators to keep the batteries recharged. Some subscribers have updated their phones using cordless phones that can be carried around. These phones will not work when the power goes out because the base station relies on the house power. For emergency purposes, it is advisable to keep around an old style telephone set that that will continue to operate when the power goes out.

Cordless Telephone

Standard Telephone

The 9-1-1 System The 9-1-1 system was developed to allow the reporting of emergencies rapidly, efficiently and without error. The diagram below shows the architecture of a modern 9-1-1 system. Originally 9-1-1 was developed to serve wireline telephone users. The service was quickly expanded to support handicapped users (deaf, non-speaking and others). The basic idea here was that since everyone was physically attached to the end of a line (wire) the location of the caller could be easily determined. When someone dialed the special code 911, that call would be directed through the phone network From an end office or a tandom office to a 9-1-1 switch as shown in the diagram.

Definitions:     ANI: Automatic Number Identification - commonly known as Caller ID. Looks up the phone number in the MSAG and returns the name of the subscriber. ALI: Automatic Location Identification - Looks up the phone number in the MSAG and returns the address of the subscriber. MSAG: Master Street Address Guide - a database that contain subscriber information. PSAP: Public Service Answering Point - also know as the 9-1-1 Call Center, Dispatch Center

When a customer makes a 9-1-1 call, the end office routes the call to a 9-1-1 switch. The switch looks up the number in a database called the MSAG (Master Street Address Guide). The MSAG contains address data for all subscribers. The lookup returns the name, address and the PSAP (Public Service Answering Point) closest to the customer. The switch uses this data to route the call to the PSAP And passes the MSAG data along to the PSAP. The PSAP is where the local emergency dispatchers are housed. A 9-1-1 dispatcher receives the call and, based up an established protocol, sends the nearest and appropriate police, fire, EMS or other units to the customer's location. The picture below shows a typical dispatcher's workstation in the PSAP. Pittsburgh's PSAP is co-located with its Emergency Operations Center (EOC) located in the Point Breeze section of the city.

The Cellular Telephone System The schematic below shows the architecture of the cellular telephone network. The customer (subscriber) has a telephone unit that communicates via radio with a cell tower. The system is designed so that there are numerous cell towers covering a region. At any time, a given subscriber's call is controlled by the cell site closest to him or her. The neighboring cells can detect the communication. When the customer moves from one cell to another, called roaming, the system automatically assigns the new cell cite as the controlling site. Call channels are allocated so that two adjacent cells do not use the same channel. Each of the cell sites is connected to a cell end office called the Mobile Telephone Switching Office (MTSO). The MTSO is connected by trunks to the Public Switched Telephone Network. This architecture allows cell phone users to call other cell phone users as well as wireline subscribers.

Cellular telephony initially provided some challenges to the 9-1-1 system. Because the cell phoen could be anywhere, the MSAG data did not give dispatchers a location to dispatch emergency equipment to. Often the callers did not know where they were. As a stopgap measure, some cellular providers provided a service by which the location of the cell phone was approximated using triangulation from the known positions of the cell towers. Next generation telephones which have Global Positioning System (GPS) capabilities built in and can transmit these to the phone company along with the call.

VOIP (Voice Over Internet Protocol) Many subscribers are using the Internet to make telephone calls through services such as Skype www.skype.com. These people can use their telephones or more usually their computers to make these calls. The customer is connected to or dials up a business called an Internet Service Provider (ISP). The ISP is connected to the Internet Service Provider is connected to the Internet directly or through a common carrier. The call is carried through the Internet which completes the call through the local carrier. This arrangement created the same kinds of problems that cellular telephones did (i.e. the 9-1-1 dispatcher did not know where the call was coming from. Efforts are being made to relate IP addresses to physical addresses to remedy theis problem.

9-1-1 Operations 9-1-1 service has evolved over the years and continues to evolve as technology changes. The sections below outline the types of 9-1-1 currently in use or planned. Basic Enhanced (E9-1-1) Wireless VOIP Reverse 9-1-1

Basic 9-1-1

When the three-digit number is dialed, a call taker/dispatcher in the local public safety answering point (PSAP), or 9-1-1 call center, answers the call. The emergency and its location are communicated by voice (or TTY) between the caller and the call taker.

Enhanced 9-1-1

The call is selectively routed to the proper PSAP for the caller’s location, and the PSAP has equipment and database information (MSAG) that display the caller's phone number and address to the call taker.

Wireless Phase I

The call taker automatically receives the wireless phone number. This is important in the event the wireless phone call is dropped, and may allow PSAP employees to work with the wireless company to identify the wireless subscriber. Phase I also delivers the location of the cell tower handling the call. The call is routed to a PSAP based on cell site/sector information.

Wireless Phase II

Phase II allows call takers to receive both the caller's wireless phone number and their location information. The call is routed to a PSAP either based on cell site/sector location information.

VoIP

Business and residential use of Voice over Internet Protocol (VoIP) telecommunications services is growing at a rapid pace. Addressing for VoIP is being added to protocols.

Reverse 9-1-1

In an emergency, a dispatcher can bulk call a list of numbers and deliver a message simultaneously. Selection of this list can be by geographic area or other criteria. In effect this is a targeted alert system.

Coverage

As of February, 2021, the United States has 5,748 (6,143) primary and secondary PSAPs and 3,135 Counties which include parishes, independent cities, boroughs and Census areas.

99.4% of 5,748 PSAPs have some Phase I  99.2% of 5,748 PSAPs have some Phase II  97.8% of 3,135 Counties have some Phase I  97.3% of 3,135 Counties have some Phase II   98.9% of Population have some Phase I  98.9% of Population have some Phase II

Call Volume

An estimated 240 million calls are made to 9-1-1 in the U.S. each year.

According to the FCC, one-third are wireless calls. In many municiplaities, it’s one-half or more of all 9-1-1 calls. Example 9-1-1 Call Center call statistics from Midland County Michigan in 2009.

Call Stats for 2009  911 Landline Calls  24,817  911 Wireless Calls  15,709  911 VOIP Calls  851  911 Hang up Calls  1895  Non-911 Calls/Admin Lines   51,196  Total calls for 2009  105,667

Most of the calls to 9-1-1 are not emergencies or minor emergencies. Following are two examples of the wide range of calls that a 9-1-1 system and its operators must deal with: The Oak Street Call The Burger Call Bad Call Overview Darnell

Trends Estimates are that nearly 29.7% of all U.S. households currently rely on wireless as their primary service. VoIP is growing at an accelerated rate. Text messages may not be the most effective.

Security Systems Technological advancements have made security features more economical for home use. The are also advantageous for 9-1-1 systems. Security vendors provide monitoring and triage for alarms such that unecessary calls are not made. Some securityy vendors have patrols that are the first situation awareness responders. Security System Vendors The list below gives some of the popular commercial and home system vendors: ADT Security Systems - www.adt.com Brinks - brinkshome.com Guardian Protection Services - guardianprotection.com Ring - ring.com SimpliSafe - simplisafe.com Verisure - www.verisure.com Vivint - www.vivint.com Security System Features Selected Examples: Motion Detectors Silent/Audible Alarms Smoke Detectors Thermal Detectors Metal Detectors RFID Detectors Cameras Panic Buttons Door/Window Open Health and Senior Safety Elevated Skin Temperature WiFi Integration

Typical Alarm System Architecture

Typical CommercialAlarm System Architecture

Typical Alarm System ContrilPanel

The N11 System

As a result of many calls to 9-1-1 not being made for emergency purposes, authorities have developed an expanded three digit dialing system for non-emergency services. An N11 number is a special abbreviated dialing telephone number within the North American Numbering Plan www.nanpa.com , which directs access to special services.

Usage is assigned as follows:

2-1-1   Community services, United Way  3-1-1   Municipal government services, non-emergency www.city.pittsburgh.pa.us/mayor/html/311_non-emergency_services.html  4-1-1   Directory assistance  5-1-1   Traffic information or police non-emergency services www.511pa.com/Traffic.aspx  6-1-1   Telephone company (Telco) customer service and repair  7-1-1   Telephone Device for the Deaf (TDD) relay for the deaf  8-1-1   Underground public utility location. PA-One Call www.pa1call.org   9-1-1   Emergency services. Region 13 www.pa-region13.org

Exercise:     Test yourself as to what you learned about the 9-1-1 emergency system. The self test can be accessed by clicking: 9-1-1 Self Test.

Government Emergency Telecommunications Service The Government Emergency Telecommunications Service (GETS) is a service available to emergency personnel. GETS is a priority service that allows critical calls to get through in times of emergency when the phone system may be clogged. The image below shows the agencies that participate in the GETS program.

The GETS Network is composed of common carriers that provide telecommunications services to the government on a regular basis: Local Exchange Carriers (LECs) (e.g. Verizon, Consolidated Communications, etc.) Wireless providers (AT&T, sprint, Verizon, etc.) Personal communications services (PCS) The major long-distance networks provided by Interexchange Carriers (IXCs) - including their international services (e.g. AT&T, Verizon Business, and Sprint) Government-leased networks Federal Technology Service (FTS) Diplomatic Telecommunication Service (DTS) Defense Switched Network (DSN) GETS Access is provided through a Universal Access Number and a Personal Identification Number (PIN). The call is identified as a priority call and receives special treatment. The GETS system can be accessed through: Common telephone equipment Standard desk set STU-III (Secure phone) Facsimile Modem Wireless phone

Qualified recipients receive a GETS card that contains all of the pertinent information for system use. Both sides of a sample card are shown below.

Emergency Communications at Pitt

University of Pittsburgh's Computing Services and Systems Development (CSSD) offers an Emergency Notification Service . Students, faculty and staff can subscribe to receive text, voice and email notifications in the event of campus emergencies. Each subscriber can designate up to three contact numbers and specify text and/or voice messages.

For voice, the caller ID will display as 412-624-1526. We recommend that you add this phone number to your address book as "Pitt ENS" so that you will recognize it immediately. For text, the message will be sent from 41526. For email, the message will be sent from ens@pitt.edu. On March 8, 2012 a gunman killed one and injured seven in an atttack at the Western Psychiatric Clinic on the Pitt Campus. The Emergency Notification System was used to notify and provide instructions those enrolled while the event was taking place. See the story in the Pitt News.

Exercise:     Sign up for Pitt's Emergency Notification Service. Identify a number of situations/events where such a notification service would be useful.

Resources:      911 Dispatch,   www.911dispatch.com  National Emergency Number Association (NENA),   www.nena.org  Cellular Telecommunications & Information Association (CTIA),   www.ctia.org National Academies of Emergency Dispatch www.emergencydispatch.org Emergency Medical Dispatch Protocol Reference System Dispatch Magazine Online www.911dispatch.com

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