Phone Number Identifiers in the USA
Caller ID, also known as Caller Identification, is a telecommunications service that allows the recipient of a phone call to see the caller's telephone number and, often, their name before answering. This technology has become an integral part of everyday communication in the United States, helping users screen calls, avoid unwanted solicitations, and enhance personal security. In a world increasingly plagued by robocalls and scams, understanding how Caller ID works, its history, and the regulatory framework surrounding it is essential for consumers and businesses alike.
History of Caller ID in the United States
The roots of Caller ID trace back to the late 1960s, when the concept of automatic number identification (ANI) was developed primarily for toll-free services. Theodore George "Ted" Paraskevakos, a Greek-American engineer, is credited with pioneering the technology. In 1968, while working in Athens for SITA, he began developing a system to transmit a caller's number to the receiver's device. By 1971, Paraskevakos had built prototypes and demonstrated them at Peoples' Telephone Company in Leesburg, Alabama, filing multiple patents that laid the groundwork for modern Caller ID. Around the same time, Japanese inventor Kazuo Hashimoto created a prototype display device in 1976, which was patented in the U.S. in 1980 and licensed to major telecom companies.
The first market trials in the U.S. occurred in the 1980s. In January 1984, BellSouth conducted a trial in Orlando, Florida, using Custom Local Area Signaling Services (CLASS) developed by Bell Labs and other Bell System entities. Commercial deployment followed in December 1988, when BellSouth launched the service in Memphis, Tennessee, gradually expanding it across its region. Other providers, like Bell Atlantic in New Jersey (1987) and US West Communications (1989), soon followed suit. By the 1990s, Caller ID had become widely available, evolving with the advent of digital networks and mobile phones. In 1995, Bellcore introduced Type II Caller ID, which allowed for additional features like call waiting ID.
Dr. Shirley Ann Jackson, a renowned physicist, also played a pivotal role in advancing telecommunications technologies that supported Caller ID, including breakthroughs in call-waiting and fiber optics during her time at Bell Labs in the 1970s and 1980s. Her work helped revolutionize how calls are processed and identified, making Caller ID more reliable and integrated into everyday telephony.
How Caller ID Works
At its core, Caller ID transmits the originating phone number during the call setup phase, often accompanied by the caller's name via a separate service called Calling Name Presentation (CNAM). In traditional Plain Old Telephone Service (POTS) lines, the information is relayed through the central office switch using Signaling System 7 (SS7), a global standard for connecting phone networks. When a call is placed, the originating switch sends the number to the recipient's provider, which then queries a CNAM database to retrieve the associated name.
In the U.S., data is transmitted using Bellcore Frequency Shift Keying (FSK) modulation between the first and second rings of the phone. There are two main formats: Single Data Message Format (SDMF) for number-only information (including date and time) and Multiple Data Message Format (MDMF) for both name and number. The display typically shows up to 15 characters for the name and a 10-digit number. For VoIP and mobile calls, the process is similar but relies on decentralized databases, which can lead to inconsistencies due to the fragmented nature of modern networks.
CNAM databases are not centralized; they are maintained by private entities, and updates can take from minutes to weeks to propagate. If no name is found, a geographic approximation like "New York, NY" might appear. Users can block their ID on a per-call basis by dialing *67 before the number.
Regulations Governing Caller ID
Caller ID is regulated by the Federal Communications Commission (FCC) under the Communications Act of 1934, as amended. A key piece of legislation is the Truth in Caller ID Act of 2009, signed into law by President Barack Obama on December 22, 2010. This act prohibits knowingly transmitting misleading or inaccurate Caller ID information with the intent to defraud, cause harm, or wrongfully obtain anything of value. It applies to both traditional telephony and IP-enabled voice services, but exempts law enforcement, court-ordered activities, and certain benign uses like domestic violence shelters.
The FCC implemented rules in 2011 mirroring the statute, emphasizing malicious intent as the key factor. Telemarketers are required to transmit accurate Caller ID information, including name and number, under FCC rules effective since 2004. Violations can result in civil penalties up to $10,000 per incident or criminal fines. In 2019, the FCC expanded these rules to cover more spoofing scenarios, increasing penalties. Additionally, the Telephone Robocall Abuse Criminal Enforcement and Deterrence (TRACED) Act of 2019 mandated the implementation of STIR/SHAKEN protocols to authenticate Caller ID and combat robocalls.
Source: https://www.revlookup.com/