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🔗 Internet 🔗 Computing 🔗 Telecommunications 🔗 Cryptography 🔗 Cryptography/Computer science

Bitmessage is a decentralized, encrypted, peer-to-peer, trustless communications protocol that can be used by one person to send encrypted messages to another person, or to multiple subscribers.

In June 2013, the software experienced a surge of new adoptions after news reports of email surveillance by the US National Security Agency.

Bitmessage was conceived by software developer Jonathan Warren, who based its design on the decentralized digital currency, bitcoin. The software was released in November 2012 under the MIT license.

Bitmessage gained a reputation for being out of reach of warrantless wiretapping conducted by the National Security Agency (NSA), due to the decentralized nature of the protocol, and its encryption being difficult to crack. As a result, downloads of the Bitmessage program increased fivefold during June 2013, after news broke of classified email surveillance activities conducted by the NSA.

Bitmessage has also been mentioned as an experimental alternative to email by Popular Science and CNET.

Some ransomware programs instruct affected users to use Bitmessage to communicate with the attackers.

🔗 Telecommunications 🔗 Systems 🔗 Business 🔗 Systems/Operations research

Virtual queuing is a concept used in inbound call centers. Call centers use an Automatic Call Distributor (ACD) to distribute incoming calls to specific resources (agents) in the center. ACDs hold queued calls in First In, First Out order until agents become available. From the caller’s perspective, without virtual queuing they have only two choices: wait until an agent resource becomes available, or abandon (hang up) and try again later. From the call center’s perspective, a long queue results in many abandoned calls, repeat attempts, and customer dissatisfaction.

Virtual queuing systems allow customers to receive callbacks instead of waiting in an ACD queue. This solution is analogous to the “fast lane” option (e.g. Disney's FASTPASS) used at amusement parks, which often have long queues to ride the various coasters and attractions. A computerized system allows park visitors to secure their place in a “virtual queue” rather than waiting in a physical queue.

In the brick-and-mortar retail and business world, virtual queuing for large organizations similar to the FASTPASS and Six Flags' Flash Pass, have been in use successfully since 1999 and 2001 respectively. For small businesses, the virtual queue management solutions come in two types: (a) based on SMS text notification and (b) apps on smartphones and tablet devices, with in-app notification and remote queue status views.

🔗 United States 🔗 Spaceflight 🔗 Telecommunications

The Iridium satellite constellation provides L-band voice and data information coverage to satellite phones, pagers and integrated transceivers over the entire Earth surface. Iridium Communications owns and operates the constellation, additionally selling equipment and access to its services. It was originally conceived by Bary Bertiger, Raymond J. Leopold and Ken Peterson in late 1987 (in 1988 protected by patents Motorola filed in their names) and then developed by Motorola on a fixed-price contract from July 29, 1993, to November 1, 1998, when the system became operational and commercially available.

The constellation consists of 66 active satellites in orbit, required for global coverage, and additional spare satellites to serve in case of failure. Satellites are in low Earth orbit at a height of approximately 781 km (485 mi) and inclination of 86.4°. Orbital velocity of the satellites is approximately 27,000 km/h (17,000 mph). Satellites communicate with neighboring satellites via K_a band inter-satellite links. Each satellite can have four inter-satellite links: one each to neighbors fore and aft in the same orbital plane, and one each to satellites in neighboring planes to either side. The satellites orbit from pole to same pole with an orbital period of roughly 100 minutes. This design means that there is excellent satellite visibility and service coverage especially at the North and South poles. The over-the-pole orbital design produces "seams" where satellites in counter-rotating planes next to one another are traveling in opposite directions. Cross-seam inter-satellite link hand-offs would have to happen very rapidly and cope with large Doppler shifts; therefore, Iridium supports inter-satellite links only between satellites orbiting in the same direction. The constellation of 66 active satellites has six orbital planes spaced 30° apart, with 11 satellites in each plane (not counting spares). The original concept was to have 77 satellites, which is where the name Iridium came from, being the element with the atomic number 77 and the satellites evoking the Bohr model image of electrons orbiting around the Earth as its nucleus. This reduced set of six planes is sufficient to cover the entire Earth surface at every moment.

Because of the shape of the original Iridium satellites' reflective antennas, the first generation satellites focus sunlight on a small area of the Earth surface in an incidental manner. This results in an effect called Iridium flares, where the satellite momentarily appears as one of the brightest objects in the night sky and can be seen even during daylight. Newer Iridium satellites do not produce flares.

🔗 Internet culture 🔗 Telecommunications 🔗 Websites 🔗 Websites/Computing

This is a list of notable active virtual communities with more than 1 million registered members.

Defunct

🔗 Technology 🔗 Physics 🔗 Telecommunications 🔗 Radio 🔗 Electronics 🔗 Engineering

In antenna theory, a phased array usually means an electronically scanned array, a computer-controlled array of antennas which creates a beam of radio waves that can be electronically steered to point in different directions without moving the antennas. The general theory of an electromagnetic phased array also finds applications in ultrasonic and medical imaging application (phased array ultrasonics) and in optics optical phased array.

In a simple array antenna, the radio frequency current from the transmitter is fed to multiple individual antenna elements with the proper phase relationship so that the radio waves from the separate elements combine (superpose) to form beams, to increase power radiated in desired directions and suppress radiation in undesired directions. In a phased array, the power from the transmitter is fed to the radiating elements through devices called phase shifters, controlled by a computer system, which can alter the phase or signal delay electronically, thus steering the beam of radio waves to a different direction. Since the size of an antenna array must extend many wavelengths to achieve the high gain needed for narrow beamwidth, phased arrays are mainly practical at the high frequency end of the radio spectrum, in the UHF and microwave bands, in which the operating wavelengths are conveniently small.

Phased arrays were originally conceived for use in military radar systems, to steer a beam of radio waves quickly across the sky to detect planes and missiles. These systems are now widely used and have spread to civilian applications such as 5G MIMO for cell phones. The phased array principle is also used in acoustics, and phased arrays of acoustic transducers are used in medical ultrasound imaging scanners (phased array ultrasonics), oil and gas prospecting (reflection seismology), and military sonar systems.

The term "phased array" is also used to a lesser extent for unsteered array antennas in which the phase of the feed power and thus the radiation pattern of the antenna array is fixed. For example, AM broadcast radio antennas consisting of multiple mast radiators fed so as to create a specific radiation pattern are also called "phased arrays".

🔗 Computing 🔗 Telecommunications 🔗 Lists

This list ranks the countries of the world by the number of mobile phone numbers in use. Note that it is not the number of phone devices that are being given here, but the number of phone numbers in a country. In some countries, one person might have two mobile phones. Also, some mobile phone numbers may be used by machines as a modem (examples: intrusion detection systems, home automation, leak detection).

🔗 Telecommunications

Signaling 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 performs number translation, local number portability, prepaid billing, Short Message Service (SMS), and other services.

In North America SS7 is often referred to as Common Channel Signaling System 7 (CCSS7). In the United Kingdom, it is called C7 (CCITT number 7), number 7 and Common Channel Interoffice Signaling 7 (CCIS7). In Germany, it is often called Zentraler Zeichengabekanal Nummer 7 (ZZK-7).

The SS7 protocol is defined for international use by the Q.700-series recommendations of 1988 by the ITU-T. Of the many national variants of the SS7 protocols, most are based on variants standardized by the American National Standards Institute (ANSI) and the European Telecommunications Standards Institute (ETSI). National variants with striking characteristics are the Chinese and Japanese Telecommunication Technology Committee (TTC) national variants.

The Internet Engineering Task Force (IETF) has defined the SIGTRAN protocol suite that implements levels 2, 3, and 4 protocols compatible with SS7. Sometimes also called Pseudo SS7, it is layered on the Stream Control Transmission Protocol (SCTP) transport mechanism for use on Internet Protocol networks, such as the Internet.

🔗 United States 🔗 Companies 🔗 Telecommunications 🔗 United States/Colorado

Qwest Communications International, Inc. was a large United States telecommunications carrier. Qwest provided local service in 14 western and midwestern U.S. states: Arizona, Colorado, Idaho, Iowa, Minnesota, Montana, Nebraska, New Mexico, North Dakota, Oregon, South Dakota, Utah, Washington, and Wyoming.

On April 22, 2010, CenturyLink announced it would acquire Qwest in a stock transaction. The merger closed on April 1, 2011. Qwest began doing business as CenturyLink in August 2011.

Qwest provided voice, Internet backbone data services, and digital television in some areas. It operated in three segments: Wireline Services, Wireless Services, and Other Services. The Wireline Services segment provided local voice, long-distance voice, and data and Internet (DSL) services to consumers, businesses, and wholesale customers, as well as access services to wholesale customers. The Wireless Services segment was achieved by a partnership with Verizon Wireless. Qwest also partnered with DirecTV to provide digital television service to its customers. In Phoenix, Denver, Salt Lake City, Boise, and Omaha, Qwest offered Qwest Choice TV (later also known as Qwest Digital Television), an IPTV service over DSL. This service was retired in October 2008 (after being no longer available to new customers in May 2008), leaving DirecTV as the only TV service Qwest provided. Qwest Choice TV customers were moved to DirecTV. The Other Services segment primarily involved the sublease of real estate assets, such as space in office buildings, warehouses, and other properties.

Qwest Communications also provided long-distance services and broadband data, as well as voice and video communications globally. The company sold its products and services to small businesses, governmental entities, and public and private educational institutions through various channels, including direct-sales marketing, telemarketing, arrangements with third-party agents, company's Web site, and partnership relations. As of September 13, 2005, Qwest had 98 retail stores in 14 states. Qwest Communications was headquartered in Denver, Colorado at 1801 California Street, in the second tallest building in Denver at 53 stories. The majority of Qwest occupational or non-management employees were represented by two labor unions; the Communications Workers of America and in Montana, the International Brotherhood of Electrical Workers. Qwest also had software development centers in Bangalore and Noida (New Delhi), India called Qwest Software Services.

🔗 International relations 🔗 France 🔗 Italy 🔗 Telecommunications 🔗 United Kingdom 🔗 Law Enforcement 🔗 Netherlands 🔗 Crime and Criminal Biography 🔗 Crime and Criminal Biography/Organized crime

EncroChat was a Europe-based communications network and service provider that offered modified smartphones allowing encrypted communication among subscribers. It was used primarily by organized crime members to plan criminal activities. Police infiltrated the network between at least March and June 2020 during a Europe-wide investigation. An unidentified source associated with EncroChat announced on the night of 12–13 June 2020 that the company would cease operations because of the police operation.

The service had around 60,000 subscribers at the time of its closure. As a result of police being able to read unencrypted EncroChat messages, at least 1,000 arrests had been made across Europe as of 22 December 2020.

🔗 Computing 🔗 Telecommunications 🔗 Computer Security 🔗 Computer Security/Computing

Phreaking is a slang term coined to describe the activity of a culture of people who study, experiment with, or explore telecommunication systems, such as equipment and systems connected to public telephone networks. The term phreak is a sensational spelling of the word freak with the ph- from phone, and may also refer to the use of various audio frequencies to manipulate a phone system. Phreak, phreaker, or phone phreak are names used for and by individuals who participate in phreaking.

The term first referred to groups who had reverse engineered the system of tones used to route long-distance calls. By re-creating these tones, phreaks could switch calls from the phone handset, allowing free calls to be made around the world. To ease the creation of these tones, electronic tone generators known as blue boxes became a staple of the phreaker community. This community included future Apple Inc. cofounders Steve Jobs and Steve Wozniak.

The blue box era came to an end with the ever-increasing use of computerized phone systems which allowed telecommunication companies to discontinue the use of in-band signaling for call routing purposes. Instead, dialing information was sent on a separate channel which was inaccessible to the telecom customer. By the 1980s, most of the public switched telephone network (PSTN) in the US and Western Europe had adopted the SS7 system which uses out-of-band signaling for call control (and which is still in use to this day). Phreaking has since become closely linked with computer hacking.