HOME

TheInfoList



OR:

Caller identification (Caller ID) is a
telephone A telephone is a telecommunications device that permits two or more users to conduct a conversation when they are too far apart to be easily heard directly. A telephone converts sound, typically and most efficiently the human voice, into e ...
service, available in analog and digital telephone systems, including
voice over IP Voice over Internet Protocol (VoIP), also called IP telephony, is a method and group of technologies for the delivery of speech, voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet. The terms In ...
(VoIP), that transmits a caller's telephone number to the
called party The called party (in some contexts called the "B-Number") is a person who (or device that) answers a telephone call. The person who (or device that) initiates a telephone call is the calling party. In some situations, the called party may number m ...
's telephone equipment when the call is being set up. The caller ID service may include the transmission of a name associated with the calling telephone number, in a service called
Calling Name Presentation Caller Name Presentation (CNAP) or Caller Name Delivery (CNAM) is used in US-based telephone networks to provide name identification of the calling party. The CNAM information is most often displayed in Caller ID. The information could be the person ...
(CNAM). The service was first defined in 1993 in
International Telecommunication Union The International Telecommunication Union is a specialized agency of the United Nations responsible for many matters related to information and communication technologies. It was established on 17 May 1865 as the International Telegraph Unio ...
—Telecommunication Standardization Sector (ITU-T) Recommendation Q.731.3. The information received from the service is displayed on a telephone display screen, on a separately attached device, or on other displays, such as cable television sets when telephone and television service is provided by the same vendor. Value to society includes use by suicide-prevention hot lines and enabling businesses "like pizza restaurants and florists" to quickly have confidence in telephoned orders. The customer has control as to whether one's full name or merely first initial appears, a choice that to avoid a fee must be selected when the initial listing is generated. Caller ID service, which is also known by similar terms such as CID, calling line identification (CLI, CLID), calling number delivery (CND), calling number identification (CNID), calling line identification presentation (CLIP), and call display, does not work with
Centrex Centrex is a portmanteau of central exchange, a kind of telephone exchange. It provides functions similar to a PBX, but is provisioned with equipment owned by, and located at, the telephone company premises. Centrex service was first installed ...
, a phone system widely used by corporations that allows outside callers to dial an extension without going through an operator.


Calling-line identification

In some countries, the terms caller display, calling line identification presentation (CLIP), call capture, or just calling line identity are used; call display is the predominant marketing name used in Canada (although some customers still refer to it colloquially as "caller ID"). The concept of calling number identification as a service for POTS subscribers originated from automatic number identification (ANI) as a part of toll free number service in the United States. However, caller ID and ANI are not equivalent services. ANI was originally a service in a non-electronic central office that identified the telephone number of the line from which a call was originated. Previous to this, the calling number could not be identified electronically. In addition to the caller's telephone number, caller ID may also transmit the subscriber's name, when available. The name can be passed on by the originating central office, or it is obtained from a line information database by the terminating switch. If no name is available, the city, State, Province, or other designation may be sent. Some of these databases may be shared among several companies, each paying every time a name is "extracted". It is for this reason that mobile phone callers appear as "WIRELESS CALLER", or the location where the phone number is registered. The displayed caller ID also depends on the equipment originating the call. If the call originates on a POTS line (a standard loop-start line), then caller ID is provided by the service provider's local switch. Since the network does not connect the caller to the callee until the phone is answered, generally the caller ID signal cannot be altered by the caller. Most service providers, however, allow the caller to block caller ID presentation through the vertical service code ''*67''. A call placed behind a private branch exchange (PBX) has more options. In the typical telephony environment, a PBX connects to the local service provider through Primary Rate Interface (PRI) trunks. Generally, although not absolutely, the service provider simply passes whatever calling line ID appears on those PRI access trunks transparently across the Public Switched Telephone Network (PSTN). This opens up the opportunity for the PBX administrator to program whatever number they choose in their external phone number fields. Some IP phone services (ITSPs, or Internet Telephony Service Providers) support PSTN gateway installations throughout the world. These gateways egress calls to the local calling area, thus avoiding long distance toll charges. ITSPs also allow a local user to have a number located in "foreign" exchange; the New York caller could have a Los Angeles number, for example. When that user places a call, the calling line ID would be that of a Los Angeles number, although they are actually located in New York. This allows a call return without having to incur long distance calling charges. With cellphones, the biggest issue appears to be in the passing of calling line ID information through the network. Cellphone companies must support interconnecting trunks to a significant number of wireline and PSTN access carriers.


CLI localisation

Calling line identity (CLI) localisation is the process of presenting a localised calling line identity to the recipient of a telephone call. CLI localisation is used by various organisations, including call centres, debt collectors and insurance companies. CLI localisation allows companies to increase their contact rate by increasing the chance that a called party will answer a phone call. Because a localised CLI is displayed on the called party's device, the call is perceived as local and recognisable to the caller rather than a withheld, unknown or premium rate number. The presented telephone number is adjusted depending on the area code of the dialed number. In 2020, the
Eastern District of Texas The United States District Court for the Eastern District of Texas (in case citations, E.D. Tex.) is a federal court in the Fifth Circuit (except for patent claims and claims against the U.S. government under the Tucker Act, which are appealed t ...
found a single missed call using a localized number was enough to trigger Article III standing under
Telephone Consumer Protection Act The Telephone Consumer Protection Act of 1991 (TCPA) was passed by the United States Congress in 1991 and signed into law by President George H. W. Bush as Public Law 102-243. It amended the Communications Act of 1934. The TCPA is codified as ...
(TCPA). The court reasoned, "At issue in this case is a missed call, not a single, unsolicited text message. It only takes one glance at a text message to recognize it is for an extended warranty for a car you have never owned or a cruise you have won from a raffle you never entered. A missed call with a familiar area code, on the other hand, is more difficult to immediately dismiss as an automated message."


History

In 1968, Theodore George "Ted" Paraskevakos, while working in as a communications engineer for
SITA Sita (; ) also called as Janaki and Vaidehi is a Hindu goddess and the female protagonist of the Hindu epic, ''Ramayana''. She is the consort of Rama, the avatar of the god Vishnu, and is regarded as a form of Vishnu's consort, Lakshmi. She ...
in
Athens, Greece Athens ( ; el, Αθήνα, Athína ; grc, Ἀθῆναι, Athênai (pl.) ) is both the capital and largest city of Greece. With a population close to four million, it is also the seventh largest city in the European Union. Athens dominates ...
, began developing a system to automatically identify a telephone caller to a call recipient. After several attempts and experiments, he developed the method in which the caller's number was transmitted to the receiver's device. This method was the basis for modern-day Caller ID technology. From 1969 through 1975, Paraskevakos was issued twenty separate patents related to automatic telephone line identification, and since they significantly predated all other similar patents, they appear as
prior art Prior art (also known as state of the art or background art) is a concept in patent law used to determine the patentability of an invention, in particular whether an invention meets the novelty and the inventive step or non-obviousness criteria ...
in later United States patents issued to
Kazuo Hashimoto was a Japanese inventor who registered over 1,000 patents throughout the world, including patents for Caller-ID system and telephone answering machine. He patented his first telephone answering machine, the Ansa Fone, in Japan in 1954, followed ...
and Carolyn A. Doughty. In 1971, Paraskevakos, working with
Boeing The Boeing Company () is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, telecommunications equipment, and missiles worldwide. The company also provides leasing and product ...
in
Huntsville, Alabama Huntsville is a city in Madison County, Limestone County, and Morgan County, Alabama, United States. It is the county seat of Madison County. Located in the Appalachian region of northern Alabama, Huntsville is the most populous city in t ...
, constructed and reduced to practice a transmitter and receiver, representing the world's first prototypes of caller-identification devices. They were installed at Peoples' Telephone Company in
Leesburg, Alabama Leesburg is a town in Cherokee County, Alabama, United States. At the 2020 census, the population was 911. History Leesburg was originally called Hamptonville; it was named for Joseph Hampton and the Henslee family respectively. A post office wa ...
, and were demonstrated to several telephone companies. These original and historic working models are still in the possession of Paraskevakos. In the patents related to these devices, Paraskevakos also proposed to send
alphanumeric Alphanumericals or alphanumeric characters are a combination of alphabetical and numerical characters. More specifically, they are the collection of Latin letters and Arabic digits. An alphanumeric code is an identifier made of alphanumeric c ...
information, such as the caller's name, to the receiving apparatus and to make banking by telephone feasible. He also proposed to identify the calling telephone by special code; e.g., "PF" for public phone, "HO" for home phone, "OF" for office phone, "PL" for police. In May 1976, Kazuo Hashimoto, a prolific
Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...
ese inventor with over one thousand patents worldwide, first built a prototype of a caller ID display device that could receive caller ID information. His work on caller ID devices and early prototypes was received in the
Smithsonian Institution The Smithsonian Institution ( ), or simply the Smithsonian, is a group of museums and education and research centers, the largest such complex in the world, created by the U.S. government "for the increase and diffusion of knowledge". Founded ...
,
National Museum of American History The National Museum of American History: Kenneth E. Behring Center collects, preserves, and displays the heritage of the United States in the areas of social, political, cultural, scientific, and military history. Among the items on display is t ...
in 2000. U.S. patent 4,242,539, filed originally on May 8, 1976, and a resulting patent re-examined at the patent office by AT&T, was successfully licensed to most of the major telecommunications and computer companies in the world. Initially, the operating telephone companies wanted to have the caller ID function performed by the central office as a voice announcement and charged on a per-call basis. John Harris, an employee of
Northern Telecom Northern may refer to the following: Geography * North, a point in direction * Northern Europe, the northern part or region of Europe * Northern Highland, a region of Wisconsin, United States * Northern Province, Sri Lanka * Northern Range, a r ...
's telephone set manufacturing division in
London, Ontario London (pronounced ) is a city in southwestern Ontario, Canada, along the Quebec City–Windsor Corridor. The city had a population of 422,324 according to the 2021 Canadian census. London is at the confluence of the Thames River, approximate ...
, promoted the idea of displaying caller ID on a telephone. The telephone was coded ECCS for ''Enhanced Custom Calling Services''. A video of his
prototype A prototype is an early sample, model, or release of a product built to test a concept or process. It is a term used in a variety of contexts, including semantics, design, electronics, and Software prototyping, software programming. A prototyp ...
was used to leverage the feature from the central office to the telephone set. In 1977, the Brazilian inventor Valdir Bravo Salinas filed a patent application for a caller ID device at the Brazilian Patent and Trademarks Office (INPI). The patent was issued in 1982 as patent PI7704466 and is the first patent issued for a caller ID equipment in
Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...
. Later in 1980, two other Brazilian inventors, João da Cunha Doya and
Nélio José Nicolai Nélio José Nicolai (c. 1940 – 11 October 2017) was a Brazilian electrotechnician who is believed to have invented caller ID. Nicolai was born in Belo Horizonte and studied at the Escola Técnica de Minas Gerais (current Federal Center for ...
, filed patent applications for other caller ID devices. Doya’s application was filed on May 2, 1980 and issued as patent PI8003077. Nicolai’s application was filed on July 2, 1980 and rejected for being a copy of Salinas' invention. In 1981 another application for a caller ID equipment was filed at the INPI by José Daniel Martin Catoira and Afonso Feijó da Costa Ribeiro Neto. This application was granted and the patent issued as patent PI8106464. The first market trial for Caller ID and other "
Custom Local Area Signaling Services A vertical service code (VSC) is a sequence of digits and the signals star (*) and number sign (#) dialed on a telephone keypad or rotary dial to enable or disable certain telephone service features. Some vertical service codes require dialing o ...
" (CLASS) was conducted by BellSouth in January 1984 in Orlando, FL after having been approached by Bell Labs (prior to AT&T's Divestiture on January 1, 1984) to conduct a trial. A press conference with ABC, NBC, CBS, and CNN was conducted announcing the event. The name Caller ID was decided by the BellSouth Product Team, purposely not trademarking the name so that other Telcos would be free to adopt the name for ubiquity. The other regional Bell operating companies later adopted the name and eventually became the generally accepted name in the United States. Planning for the trial was initiated by a team in
Bell Laboratories Nokia Bell Labs, originally named Bell Telephone Laboratories (1925–1984), then AT&T Bell Laboratories (1984–1996) and Bell Labs Innovations (1996–2007), is an American industrial research and scientific development company owned by mult ...
,
AT&T AT&T Inc. is an American multinational telecommunications holding company headquartered at Whitacre Tower in Downtown Dallas, Texas. It is the world's largest telecommunications company by revenue and the third largest provider of mobile tel ...
, and
Western Electric The Western Electric Company was an American electrical engineering and manufacturing company officially founded in 1869. A wholly owned subsidiary of American Telephone & Telegraph for most of its lifespan, it served as the primary equipment ma ...
before the
Bell System divestiture The breakup of the Bell System was mandated on January 8, 1982, by an agreed consent decree providing that AT&T Corporation would, as had been initially proposed by AT&T, relinquish control of the Bell Operating Companies, which had provided loc ...
, with the participation of Bell Atlantic. The purpose of these trials was to assess the revenue potential of services that depend on deployment of the common channel signaling network needed to transmit the calling number between originating and terminating central offices. Trial results were analyzed by
Bellcore iconectiv is a supplier of network planning and network management services to telecommunications providers. Known as Bellcore after its establishment in the United States in 1983 as part of the break-up of the Bell System, the company's name ...
members of the original team. In 1987, Bell Atlantic (now
Verizon Communications Verizon Communications Inc., commonly known as Verizon, is an American multinational telecommunications conglomerate and a corporate component of the Dow Jones Industrial Average. The company is headquartered at 1095 Avenue of the Americas i ...
) conducted another market trial in
Hudson County, New Jersey Hudson County is the most densely populated county in the U.S. state of New Jersey. It lies west of the lower Hudson River, which was named for Henry Hudson, the sea captain who explored the area in 1609. Part of New Jersey's Gateway Region in t ...
, which was followed by limited deployment. BellSouth was the first company to deploy Caller ID commercially in December 1988 in
Memphis, Tennessee Memphis is a city in the U.S. state of Tennessee. It is the seat of Shelby County in the southwest part of the state; it is situated along the Mississippi River. With a population of 633,104 at the 2020 U.S. census, Memphis is the second-mos ...
, with a full deployment to its nine-state region over the next four years. Bell Atlantic was the second local telephone company to deploy Caller ID in New Jersey's Hudson County, followed by US West Communications (now
CenturyLink Lumen Technologies, Inc. (formerly CenturyLink) is an American telecommunications company headquartered in Monroe, Louisiana, that offers communications, network services, security, cloud solutions, voice, and managed services. The company is ...
) in 1989.


Type II caller ID

In 1995, Bellcore released another type of
modulation In electronics and telecommunications, modulation is the process of varying one or more properties of a periodic waveform, called the ''carrier signal'', with a separate signal called the ''modulation signal'' that typically contains informatio ...
, similar to
Bell 202 The Bell 202 modem was an early (1976) modem standard developed by the Bell System. It specifies audio frequency-shift keying (AFSK) to encode and transfer data at a rate of 1200 bits per second, half-duplex. It has separate sets of circuits fo ...
, with which it became possible to transmit caller ID information and even provide call-disposition options while the user was already on the telephone. This not-for-free service became known in some markets as call waiting ID, or (when it was combined with call-disposition options) Call Waiting Deluxe; it is technically referred to as
Analog Display Services Interface {{Update, date=March 2018 Analog Display Services Interface (ADSI) is a telephony technology that is used in plain old telephone service (POTS) or computer-based private branch exchange (PBX) telephone service. It works in conjunction with a ...
. "Call Waiting Deluxe" is the Bellcore (now
Telcordia Technologies iconectiv is a supplier of network planning and network management services to telecommunications providers. Known as Bellcore after its establishment in the United States in 1983 as part of the break-up of the Bell System, the company's name ...
) term for Type II caller ID with Disposition Options. This class-based POTS-telephone calling feature works by combining the services of
call waiting Call waiting is a telephone service where a subscriber can accept a second incoming telephone call by placing an in-progress call on hold—and may also switch between calls. With some providers it can be combined with additional features such as ...
with caller ID but also introduces an "options" feature that, in conjunction with certain screen-based telephones, or other capable equipment, gives a telephone user the option to * Switch: Place the current call on hold to take the second call (not a new feature) * Hang-up: Disconnect the current call and take the second call (not a new feature) * Please Hold: Send the caller either a custom or telephone-company-generated voice message asking the caller to hold * Forward to Voice Mail: Send the incoming caller to the recipient’s
voice mail A voicemail system (also known as voice message or voice bank) is a computer-based system that allows users and subscribers to exchange personal voice messages; to select and deliver voice information; and to process transactions relating to ind ...
service. * Join: Add the incoming caller to the existing conversation. data checksum digit d1 d2 d3 d4 s1 s2 s3 s4 1 1 0 0 0 1 1 1 1 2 0 1 0 0 0 1 1 1 3 1 1 0 0 1 0 1 1 4 0 0 1 0 0 0 1 1 5 1 0 1 0 1 1 0 1 6 0 1 1 0 0 1 0 1 7 1 1 1 0 1 0 0 1 8 0 0 0 1 0 0 0 1 9 1 0 0 1 1 1 1 0 0 0 1 0 1 0 1 1 0 * 1 1 0 1 1 0 1 0 # 0 0 1 1 0 0 1 0 A 1 0 1 1 1 1 0 0 B 0 1 1 1 0 1 0 0 C 1 1 1 1 1 0 0 0 D 0 0 0 0 0 0 0 0 FSK mark= 1200 Hz space= 2200 Hz 1200 bpsk The above flexibility requires the immediate presence of both a phone and a display screen, not one "several rooms away" from the other. By 2007, Verizon and AT&T had bundled these services with still others, including speed dialling, "free" inside wiring maintenance, and unlimited minutes. The result was increased monthly spending for those customers adding features, but reduced individual charges for those options they already had.


Operation

In the United States and Canada, caller ID information is sent to the called party by the
telephone switch telephone exchange, telephone switch, or central office is a telecommunications system used in the public switched telephone network (PSTN) or in large enterprises. It interconnects telephone subscriber lines or virtual circuits of digital syste ...
as an analog data stream (similar to data passed between two
modem A modulator-demodulator or modem is a computer hardware device that converts data from a digital format into a format suitable for an analog transmission medium such as telephone or radio. A modem transmits data by Modulation#Digital modulati ...
s), using Bell 202 modulation between the first and second rings, while the telephone unit is still on hook. If the telephone call is answered too quickly after the first ring, caller ID information may not be transmitted to the recipient. Also, in the United States and Canada a caller may block the display of the number they are calling from by dialling *67 before dialling the phone number. This will not work when dialling an "800" number, where the receiver of the call pays for the call or when 911 emergency calls are made. There are two types of caller ID: number-only and name+number. Number-only caller ID is called Single Data Message Format (SDMF), which provides the caller's telephone number, the date and time of the call. Name+number caller ID is called Multiple Data Message Format (MDMF), which in addition to the information provided by SDMF format, can also provide the directory listed name for the particular number. Caller ID readers which are compatible with MDMF can also read the simpler SDMF format, but an SDMF caller ID reader will not recognize an MDMF data stream, and will act as if there is no caller ID information present, e.g. as if the line is not equipped for caller ID. Instead of sending the caller ID in between the first and second ring, some systems (such as in the UK) use
line reversal Line most often refers to: * Line (geometry), object with zero thickness and curvature that stretches to infinity * Telephone line, a single-user circuit on a telephone communication system Line, lines, The Line, or LINE may also refer to: Arts ...
to announce the caller ID, or caller ID signals are simply sent without any announcement. Instead of Bell 202, the European alternative
V.23 ''V.'' is the debut novel of Thomas Pynchon, published in 1963. It describes the exploits of a discharged United States Navy, U.S. Navy sailor named Benny Profane, his reconnection in New York City, New York with a group of pseudo-bohemianism, b ...
is sometimes used (without the 75-baud reverse channel) or the data is sent using
DTMF Dual-tone multi-frequency signaling (DTMF) is a telecommunication signaling system using the voice-frequency band over telephone lines between telephone equipment and other communications devices and switching centers. DTMF was first developed ...
signalling. In general, CID as transmitted from the origin of the call is only the calling party's full phone number (including area code, and including international access code and country code if it's an international call). The calling party name is added by the consumer's terminating central office if the consumer has subscribed to that service. Calling name delivery is not automatic. A query (dip) with
Signalling System 7 Signalling System No. 7 (SS7) is a set of telephony signaling protocols developed in 1975, which is used to set up and tear down telephone calls in most parts of the world-wide public switched telephone network (PSTN). The protocol also perform ...
(SS7) query may be initiated by the called party's central office to retrieve the information for Calling Name delivery to the caller ID equipment at the subscriber's location, if the caller's name has not already been associated with the calling party's line at the originating central office. Canadian systems (depending on the provider) using CCS7 automatically (but not in all cases) send the calling name with the call set-up and routing information at the time of the call. To look up the name associated with a phone number, the carrier, in some instances, has to access that information from a third-party database, and some database providers charge a small fee for each access to such databases. This CNAM dip fee is very small – less than a penny per call. AT&T starts their negotiations for CNAM dip fees at about $.004 per lookup. OpenCNAM fees are a bit more expensive, up to $.0048 per lookup. To avoid such charges, some carriers will report the name as "unavailable", or will report the name as "''(city), (state)''" based on the phone number, particularly for wireless callers. For toll-free numbers, they may report a string such as if the name is not available in a database.
Smartphone A smartphone is a portable computer device that combines mobile telephone and computing functions into one unit. They are distinguished from feature phones by their stronger hardware capabilities and extensive mobile operating systems, whic ...
s can use a third-party
mobile app A mobile application or app is a computer program or software application designed to run on a mobile device such as a phone, tablet, or watch. Mobile applications often stand in contrast to desktop applications which are designed to run on d ...
to do the name lookup in a third-party database.


Uses


Telemarketing

Telemarketing organisations often spoof caller ID. In some instances, this is done to provide a "central number" for consumers to call back, such as a toll-free number, rather than having consumers call back the outbound call center where the call actually originated. However, some telemarketers block or fraudulently spoof caller ID to prevent being traced. It is against United States federal law for telemarketers to block or to send misleading caller ID. Individuals may file
civil suit - A lawsuit is a proceeding by a party or parties against another in the civil court of law. The archaic term "suit in law" is found in only a small number of laws still in effect today. The term "lawsuit" is used in reference to a civil act ...
s and the
Federal Communications Commission The Federal Communications Commission (FCC) is an independent agency of the United States federal government that regulates communications by radio, television, wire, satellite, and cable across the United States. The FCC maintains jurisdiction ...
(FCC) can
fine Fine may refer to: Characters * Sylvia Fine (''The Nanny''), Fran's mother on ''The Nanny'' * Officer Fine, a character in ''Tales from the Crypt'', played by Vincent Spano Legal terms * Fine (penalty), money to be paid as punishment for an offe ...
companies or individuals for illegally spoofing or blocking caller ID.


Mobile providers

Most mobile phone providers used the caller ID to automatically connect to voice mail when a call to the voice mail number was made from the associated mobile phone number, bypassing the need to enter a password. While this was convenient for many users, because of spoofing, this practice has been replaced by more secure authentication by many carriers.


Regional differences

Caller ID transmission is implemented using different technologies and standards in some countries. In the United States the Bellcore FSK standard is prevalent, whereas Taiwan uses ETSI FSK. Sometimes individual service providers within a country use different standards. Caller ID converters can be used to translate from one standard to another.


UK

Telephone equipment usually displays CLID information with no difficulty. Modems are notoriously problematic; very few modems support the
British Telecom BT Group plc (trade name, trading as BT and formerly British Telecom) is a British Multinational corporation, multinational telecommunications holding company headquartered in London, England. It has operations in around 180 countries and is th ...
standard in hardware; drivers for those that do often have errors that prevent CLID information from being recognised. Other UK telephone companies use slight variations on the Bellcore standard, and CLID support is "hit and miss".


Australia

CND is currently available in Australia to subscribers to the Integrated Services Digital Network (ISDN). There is a legislation under section 276 of the Australia Industry Code - Calling Number Display (ACIF C522: February 2003).


Legal issues


United States

In the United States, telemarketers are required to transmit caller ID. This requirement went into effect on January 29, 2004. It is generally illegal to spoof Caller ID if done "with the intent to defraud, cause harm, or wrongfully obtain anything of value". The acts are prohibited under Truth in Caller ID Act of 2009. Courts have ruled that caller ID is admissible. Providers are required by FCC rules to offer "per-call" blocking of caller ID to their customers. Legislation in the United States in made
caller ID spoofing Caller ID spoofing is the practice of causing the telephone network to indicate to the receiver of a call that the originator of the call is a station other than the true originating station. This can lead to a caller ID display showing a phone ...
illegal for fraudulent purposes. In March 2017 the FCC approved a new rule that would allow telecommunication companies to block robocallers that use fake caller ID numbers to conceal their true location and identity. The rule means telecommunication companies can block robocallers at the network level, long before a call passes through a carriers network and arrives at a subscriber's house or business. T-Mobile was the first major US carrier to announce plans to implement blocking technologies based on the new rule. Starting in mid-2017, and with intended culmination in 2019, the FCC pushed forward Caller ID certification implemented via a methodology of
SHAKEN/STIR STIR/SHAKEN, or SHAKEN/STIR, is a suite of protocols and procedures intended to combat caller ID spoofing on public telephone networks. Caller ID spoofing is used by robocallers to mask their identity or to make it appear the call is from a legi ...
. This initiative was further strengthened by the TRACED Act, enacted in December 2019.


Blocking and unblocking caller ID

Caller ID blocking is the common term for a service by which a caller can prevent the display of the calling number on the recipient's telephone. Blocking the number is formally referred to as ''calling line identification restriction'' (CLIR). This customer option was part of the legal authorization for New York State's 1992 authorization of Caller ID. Telecommunications regulators vary in their requirements for the use and effectiveness of assorted technologies to prevent numbers from being displayed. Generally,
unlisted number In telephony, an unlisted number (United States, New Zealand), ex-directory number (United Kingdom) silent number, silent line (Australia), or private number (New Zealand, and Canada) is a telephone number that, for a fee, is intentionally not l ...
s are always blocked. Non-published and regular listed numbers are not usually blocked. But there is varying treatment for the determination of call display blocking because of many factors. If desired, customers should inquire carefully to make sure their number will not be displayed. The telephone service provider may also have vertical service codes which can be dialed to configure blocking as active for all calls or on a call-by-call basis. In some locations in the United States, regulations allow (or require) blocking to be automatic and transparent to the caller. Where blocking is applied on a call-by-call basis (that is, at the time a call is made), subscribers can block their caller ID by dialing a special code (a vertical service code, or VSC) before making a call. In
North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...
and some other regions, the code is *67 (1167 on rotary phones), while in the
United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and North ...
and
Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...
, it is 141. This special code does not block the information from companies using call capture technology. This means that equipment with caller ID will simply display the word "PRIVATE" or "WITHHELD". When CNID is blocked at the caller's request, the number is actually transmitted through the entire telephone network, with the "presentation withheld" flag set; the destination CO is expected to honor this flag, but sometimes does not—especially when the destination phone number is served by an ISDN PRI. Alternatively, in cases where caller ID is being blocked automatically, it can only be released on a call-by-call basis by dialing a special code (*82 in North America; 1470 in the UK). See "Enabling", below. Similarly, some countries offer anonymous caller rejection, which rejects all calls when the subscriber's name, number (or both) is blocked. Some
telephone companies A telephone company, also known as a telco, telephone service provider, or telecommunications operator, is a kind of communications service provider (CSP), more precisely a telecommunications service provider (TSP), that provides telecommunica ...
protect their clients from receiving calls with blocked information by routing anonymous calls to a service (such as AT&T Privacy Manager), where the caller is required to announce himself or herself. The service then asks the called party if they want to accept or reject the call. Other telephone companies play a recording to the caller advising them of the called party's rejection configuration, and often offer advice (such as prefixing their dialing with *82) on how to get their call to the intended called party. Emergency services will most likely be able to show the restricted number using a service called ''calling line identification restriction override'' (CLIRO), or by using general ANI services. These features create a
cat-and-mouse game Cat and mouse, often expressed as cat-and-mouse game, is an English-language idiom that means "a contrived action involving constant pursuit, near captures, and repeated escapes." The "cat" is unable to secure a definitive victory over the "mous ...
situation,(
Wired ''Wired'' (stylized as ''WIRED'') is a monthly American magazine, published in print and online editions, that focuses on how emerging technologies affect culture, the economy, and politics. Owned by Condé Nast, it is headquartered in San Fra ...
)
whereby subscribers must purchase additional services in order to cancel out other services.


Disabling caller ID delivery

Depending on the operator and country, there are a number of prefix codes that can block or disable Caller ID transmission by the caller. Prefixing a telephone number with the following codes disables Caller ID on a per-call basis: Other countries and networks vary; however, on
GSM The Global System for Mobile Communications (GSM) is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe the protocols for second-generation ( 2G) digital cellular networks used by mobile devices such ...
mobile networks, callers may dial #31# before the number they wish to call to disable it. Some countries and network providers do not allow Caller ID blocking based on the domestic telecommunications regulations, or CLIR is only available as an external app or value-added service.


Enabling caller ID delivery

Depending on the operator and country, there are a number of prefix codes that can unblock or enable Caller ID transmission by the caller. On GSM mobile networks, callers may dial *31# to enable caller ID on all subsequent calls.


Caller ID spoofing

Caller ID spoofing is the practice of causing the telephone network to display a number on the recipient's caller ID display that is different than that of the actual originating station. Many telephone services, such as ISDN PRI based PBX installations, and
voice over IP Voice over Internet Protocol (VoIP), also called IP telephony, is a method and group of technologies for the delivery of speech, voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet. The terms In ...
services, permit the caller to configure customized caller ID information. In corporate settings this permits the announcement of switchboard number or customer service numbers. Caller ID spoofing may be
illegal Illegal, or unlawful, typically describes something that is explicitly prohibited by law, or is otherwise forbidden by a state or other governing body. Illegal may also refer to: Law * Violation of law * Crime, the practice of breaking the ...
in some countries or in certain situations.


Dip fee fraud

A consumer's telephone company must pay a small fee for the Caller ID text that is transmitted during a call. The fee is called a CNAM dip fee. It is named a dip fee because the called party's carrier pays a fee to dip into the originating telephone company's database to get the Caller ID information. Several companies engage in generating dip fees by catering to companies that make a large number of outbound calls. CallerId4U and Pacific Telecom Communications Group cater to telemarketers and generate revenue on fees from Caller ID information. The telemarketers enter into an agreement with companies like CallerId4U and Pacific Telecom Communications Group and share the revenue produced during the telemarketing call. Dip fees vary wildly. According to Doug McIntyre, the wholesale rates are on the order of $0.002 to $0.006 per database dip. And according to Aaron Woolfson, president of TelSwitch Inc, the fee structure for dip fee fraud can include: * the carriers pay a fee of $0.003 per call or $300 per 100,000 calls to the database owner * the database owner pays the number dealers $0.0024 per call or $240 per 100,000 calls * the number dealers share revenue with the robocaller $0.00096 or $96 per 100,000 calls Consumers face significant barriers to exiting a call list and often cannot have themselves removed from the list. Calling the opt-out numbers often results in a fast-busy so the call never completes and the consumer remains on the list. According to reports companies like CallerId4U has thousands of phone numbers and thousands of FTC complaints filed against them each month for violating Do Not Call registration. The large number of phone numbers dilute the number of complaints against the company and phone number.


Trivia

* The inverse feature, giving the number originally dialed, is known as
direct inward dialing Direct inward dialing (DID), also called direct dial-in (DDI) in Europe and Oceania, is a telecommunication service offered by telephone companies to subscribers who operate a private branch exchange (PBX) system. The feature provides service for ...
, direct dialing inward, or
Dialed Number Identification Service Dialed Number Identification Service (DNIS) is a service offered by telecommunications companies to corporate clients which identifies the originally dialed telephone number of an inbound call. The client may use this information for call routing to ...
. This tells the PBX where to route an incoming call, when there are more internal lines with external phone numbers than there are actual incoming lines in a large company or other organisation. * Not all types of caller identification use 202-type modulation, nor do all systems send the information between the first and second ring, e.g., British Telecom sends the signal before the first ring, after a polarity reversal in the line. (Because of this most caller ID software is not compatible with BT even if the modem is.) As a result, not all caller ID devices are compatible from country to country or within the same country, even though the basic phone system is the same. Some providers use
FSK FSK may refer to: * FSK (band), a German band * Federal Counterintelligence Service, (Russian ') of Russia * Fiskerton railway station, in England * Forskolin, a diterpene * Forsvarets Spesialkommando, a Norwegian special forces unit * Fort Scott M ...
, while others use the DTMF protocol.


See also

*
Calling Name Presentation Caller Name Presentation (CNAP) or Caller Name Delivery (CNAM) is used in US-based telephone networks to provide name identification of the calling party. The CNAM information is most often displayed in Caller ID. The information could be the person ...
*
Local number portability Local number portability (LNP) for fixed lines, and full mobile number portability (FMNP) for mobile phone lines, refers to the ability of a "customer of record" of an existing fixed-line or mobile telephone number assigned by a local exchange ca ...
* Location Routing Number * Truth in Caller ID Act of 2009


References


External links


Report and Order from the FCC on Implementing the Telephone Consumer Protection Act of 1991, including rules and discussion of caller ID issues.





Additional MDMF details

Unknown Numbers Service - donotcalled.com
{{DEFAULTSORT:Caller Id Calling features Authentication methods Telephone service enhanced features Telecommunications-related introductions in 1987