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45-571: Planning of the cables started in 2002 by the Norwegian Space Centre (NSC), who wanted increased bandwidth to expand their business at Svalbard Satellite Station (SvalSat). At the time all telecommunications from Svalbard were relayed via communications satellite . Financing was secured through a deal with the National Aeronautics and Space Administration (NASA). The cable system was supplied by Tyco Telecommunications and laying of

90-509: A US$ 300,000 detailed study for Tyco to advance the planning. Hannon Armstrong was selected as a financial partner and the money was guaranteed by the Ministry of Trade and Industry . The first work took place at Breivika: the land-owner was contacted on 7 May, a sales agreement was signed on 13 May, permits were finalized on 23 May, construction started the next day and the NOK ;5-million facility

135-622: A commercial basis for undertaking both domestic and international missions. During the 2010s, the agency has been a partner in the development of the Nucleus hybrid sounding rocket, which is intended to be safer, cheaper, and more environmentally-friendly than prior models. During February 2019, the Norwegian Space Centre was formally renamed as the Norwegian Space Agency; according to Communication Director Marianne Moen, this change

180-403: A form of non-computer voting logic. The simplest voting logic in computing systems involves two components: primary and alternate. They both run similar software, but the output from the alternate remains inactive during normal operation. The primary monitors itself and periodically sends an activity message to the alternate as long as everything is OK. All outputs from the primary stop, including

225-573: A member states of the European Space Agency (ESA). That same year, Norwegian Space Centre was established as a government body responsible for organising Norwegian space activities, particularly those related to the ESA and other international efforts, as well as its work in coordinating national efforts. One of its roles is to manage and distribute funding to most efficiently support the space sector and benefit Norwegian interests. Proposals produced by

270-514: A period of six years. The fiber cable system runs from Harstad via Breivika on the island of Andøya to Hotellneset on Svalbard. The system consists of two separate cables, Segment 1 and Segment 2 between Breivika and Hotellneset, and Segment 1A and Segment 2A between Breivika and Harstad. The lengths for Segment 1 and 2 are 1,375 and 1,339 kilometers (854 and 832 mi), respectively, and for Segment 1A and 2A 61 and 74 kilometers (38 and 46 mi). Both cables have eight fiber pairs, of which only one

315-531: A power line when monitors detect an overload. Power is redistributed across the remaining lines. At the Toronto Airport, there are 4 redundant electrical lines. Each of the 4 lines supply enough power for the entire airport. A spot network substation uses reverse current relays to open breakers to lines that fail, but lets power continue to flow the airport. Electrical power systems use power scheduling to reconfigure active redundancy. Computing systems adjust

360-415: A system that operates at higher speeds, but less safely. Voting logic uses performance monitoring to determine how to reconfigure individual components so that operation continues without violating specification limitations of the overall system. Voting logic often involves computers, but systems composed of items other than computers may be reconfigured using voting logic. Circuit breakers are an example of

405-412: A twin cable ring for US$ 40 million. However, the cable-laying companies were not willing to accept a payment over seven years. Tyco Communications was announced as the winner on 7 March and negotiations were finalized on 14 April, as a turnkey contract on the condition that the cable could be financed. The main difficulty was that NSC, a foundation , had very little equity, and spent most of its cash on

450-737: Is entirely owned by the Government of Norway . The company has been allocated a 50% stake in Kongsberg Satellite Services , which specialises in reading data from in-orbit Earth observation satellites on behalf of various satellite owners. In July 2019, Space Norway contracted with American companies Northrop Grumman and SpaceX to build and launch respectively its two-satellite Arctic Satellite Broadband Mission (ASBM) system, which launched in August 2024. Redundancy (engineering) In engineering and systems theory , redundancy

495-420: Is impaired. Hearing loss in one ear does not cause deafness but directionality is lost. Performance decline is commonly associated with passive redundancy when a limited number of failures occur. Active redundancy eliminates performance declines by monitoring the performance of individual devices, and this monitoring is used in voting logic. The voting logic is linked to switching that automatically reconfigures

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540-476: Is in use. Use of additional pairs requires new equipment to be installed in Harstad and Hotellneset. Segment 2 is redundant to Segment 1 and is only used if the former should fall out. Near shore the cables are armored. On the main section, each segment is equipped with twenty optical communications repeaters. These run off direct current fed from Breivika, with the seawater and seabed used for return current. Power

585-402: Is necessary to pick up the cables, the power feed equipment can send a 4 to 5 hertz sine wave through the high-voltage output, which can be detected on the seabed. Line terminating equipment (LTE) is installed at Longyearbyen and Harstad. The system is capable of handling the entire length without regeneration of the signal. It employs clear-channel transmission, which is protocol-independent, with

630-465: Is one form of robustness as practiced in computer science . Geographic redundancy has become important in the data center industry, to safeguard data against natural disasters and political instability (see below). In computer science, there are four major forms of redundancy: A modified form of software redundancy, applied to hardware may be: Structures are usually designed with redundant parts as well, ensuring that if one part fails,

675-598: Is provided through a single-end feed; although supplying from both ends is safer, a single feed was regarded as sufficient. The cables are fed 1.1 ampere at 2,500 volt , fed from two redundant converters . Each repeater has eight erbium doped fiber amplifier pairs. The pairs operate independently of each other, including having their own power supply, allowing for redundancy should one fall out. The repeaters have an estimated lifetime of twenty-five years. The cables are equipped with an ocean ground protection panel to provide isolation and thus hinder damage from lightning. If it

720-418: Is required for voting). Redundancy may also be known by the terms "majority voting systems" or "voting logic". Redundancy sometimes produces less, instead of greater reliability – it creates a more complex system which is prone to various issues, it may lead to human neglect of duty, and may lead to higher production demands which by overstressing the system may make it less safe. Redundancy

765-418: Is the intentional duplication of critical components or functions of a system with the goal of increasing reliability of the system , usually in the form of a backup or fail-safe , or to improve actual system performance, such as in the case of GNSS receivers, or multi-threaded computer processing. In many safety-critical systems , such as fly-by-wire and hydraulic systems in aircraft , some parts of

810-600: The International Space Station ; various space-based missions have also sourced technologies from Norway. The country has also been a location for testing equipment bound for extraterrestrial use to evaluate its ability to withstand local conditions. During 1997, the Andøya Space Center was privatised , the Norwegian Space Center acquired a 90% stake in it as a consequence; the center is run on

855-461: The 1960s, Norway started routinely funding satellite communications research, which has helped the country develop itself as the optimum location for receiving date from satellites stationed in a polar orbit . Norway was reportedly the first nation to use satellite communicates inland, enabling it to better support its oil industry and remote sites in the Arctic wilderness. During 1987, Norway became

900-731: The EU space programmes and in bilateral agreements with other countries. Its headquarters is located in Oslo . Norway has been engaged in space activities since the 1960s, well before the agency's founding. On 18 August 1962, the first rocket was launched from the Andøya Space Center in Vesterålen , Norway; this facility has been in regular use as a launch site for space-bound vehicles ever since. By 2012, in excess of 1,000 sounding rockets had reportedly been launched from Norwegian soil. Furthermore, since

945-429: The activity message, when the primary detects a fault. The alternate activates its output and takes over from the primary after a brief delay when the activity message ceases. Errors in voting logic can cause both outputs to be active or inactive at the same time, or cause outputs to flutter on and off. A more reliable form of voting logic involves an odd number of three devices or more. All perform identical functions and

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990-534: The archipelago to the mainland was unexpectedly severed in January 2022. A preliminary police investigation implicates human activity. Norwegian Space Centre The Norwegian Space Agency ( NOSA ) (formerly the Norwegian Space Centre ( NSC ); Norwegian : Norsk Romsenter ) is a Norwegian government agency that follows Norway's public space activities. NOSA's goal is to ensure that Norway benefits from any space activity in which Norway engages in. The agency

1035-561: The body are overseen by the Norwegian Ministry of Trade and Industry . Since the agency's founding, Norway has continued to expand its space-based activities. The nation hosts the largest ground station for the Galileo global navigation satellite system (GNSS). Norwegian-built components have been integrated into many satellites in addition to the Ariane 5 heavy-lift launch vehicle and

1080-481: The cable was carried out by Global Marine Systems in July and August 2003. Svalbard was chosen for the location of SvalSat because of its high latitude which allows all satellites in a low Earth orbit with an orbit above 500 kilometers (310 mi) to use only a single ground station, yet allow downloading from every orbit. SvalSat opened on 15 April 1999. It was established as a cooperation between NASA and NS. However,

1125-528: The components. Error detection and correction and the Global Positioning System (GPS) are two examples of active redundancy. Electrical power distribution provides an example of active redundancy. Several power lines connect each generation facility with customers. Each power line includes monitors that detect overload. Each power line also includes circuit breakers. The combination of power lines provides excess capacity. Circuit breakers disconnect

1170-437: The control system may be triplicated, which is formally termed triple modular redundancy (TMR). An error in one component may then be out-voted by the other two. In a triply redundant system, the system has three sub components, all three of which must fail before the system fails. Since each one rarely fails, and the sub components are designed to preclude common failure modes (which can then be modelled as independent failure),

1215-687: The entire structure will not collapse. A structure without redundancy is called fracture-critical , meaning that a single broken component can cause the collapse of the entire structure. Bridges that failed due to lack of redundancy include the Silver Bridge and the Interstate 5 bridge over the Skagit River . Parallel and combined systems demonstrate different level of redundancy. The models are subject of studies in reliability and safety engineering. Unlike traditional redundancy, which uses more than one of

1260-465: The following Geographic redundancy corrects the vulnerabilities of redundant devices deployed by geographically separating backup devices. Geographic redundancy reduces the likelihood of events such as power outages , floods , HVAC failures, lightning strikes, tornadoes , building fires, wildfires , and mass shootings disabling most of the system if not the entirety of it. Geographic redundancy locations can be The following methods can reduce

1305-458: The former's connection to the fiber network. NSC was in October offered various prices between US$ 30 and 40 million for the laying of a single fiber cable. NSC conducted negotiations with NASA on 31 October 2002, resulting in an understanding of NASA being able to provide $ US20 million towards the line, paid over seven years. The following day Telenor stated they were not interested in participating in

1350-467: The ground station's capacity was limited by its broadband capacity. Transmission took place via a 55-Mbit/s connection via Intelsat , which served the archipelago's needs within telephone and Internet connection. Telenor and the NSC conducted a feasibility study in 2002 for connecting SvalSat to the mainland by fiber. It was estimated to cost between NOK 400 and 500 million, or US$ 50 million, which presumed

1395-423: The impact of component failures. One common form of passive redundancy is the extra strength of cabling and struts used in bridges. This extra strength allows some structural components to fail without bridge collapse. The extra strength used in the design is called the margin of safety. Eyes and ears provide working examples of passive redundancy. Vision loss in one eye does not cause blindness but depth perception

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1440-770: The laying of one cable with satellite used as backup. A stakeholder meeting was held on 24 and 25 July, which saw representatives from NASA, the Integrated Programme Office (IPO), the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) and the European Space Agency (ESA). Later that year the National Polar-orbiting Operational Environmental Satellite System selected Helsinki over Svalbard for its ground station, largely because of

1485-457: The outputs are compared by the voting logic. The voting logic establishes a majority when there is a disagreement, and the majority will act to deactivate the output from other device(s) that disagree. A single fault will not interrupt normal operation. This technique is used with avionics systems, such as those responsible for operation of the Space Shuttle . Each duplicate component added to

1530-424: The probability of all three failing is calculated to be extraordinarily small; it is often outweighed by other risk factors, such as human error . Electrical surges arising from lightning strikes are an example of a failure mode which is difficult to fully isolate, unless the components are powered from independent power busses and have no direct electrical pathway in their interconnect (communication by some means

1575-596: The production output of each generating facility when other generating facilities are suddenly lost. This prevents blackout conditions during major events such as an earthquake. Charles Perrow , author of Normal Accidents , has said that sometimes redundancies backfire and produce less, not more reliability. This may happen in three ways: First, redundant safety devices result in a more complex system, more prone to errors and accidents. Second, redundancy may lead to shirking of responsibility among workers. Third, redundancy may lead to increased production pressures, resulting in

1620-554: The risks of damage by a fire conflagration : Geographic redundancy is used by Amazon Web Services (AWS), Google Cloud Platform (GCP), Microsoft Azure, Netflix, Dropbox, Salesforce, LinkedIn, PayPal, Twitter, Facebook, Apple iCloud, Cisco Meraki, and many others to provide geographic redundancy, high availability, fault tolerance and to ensure availability and reliability for their cloud services. As another example, to minimize risk of damage from severe windstorms or water damage, buildings can be located at least 2 miles (3.2 km) away from

1665-716: The same socket in such a way that if one power supply failed, the other would too. It also assumes that only one component is needed to keep the system running. You can achieve higher availability through redundancy. Let's say you have three redundant components: A, B and C. You can use following formula to calculate availability of the overall system: Availability of redundant components = 1 - (1 - availability of component A) X (1 - availability of component B) X (1 - availability of component C) In corollary, if you have N parallel components each having X availability, then: Availability of parallel components = 1 - (1 - X)^ N Using redundant components can exponentially increase

1710-429: The same thing, dissimilar redundancy uses different things. The idea is that the different things are unlikely to contain identical flaws. The voting method may involve additional complexity if the two things take different amounts of time. Dissimilar redundancy is often used with software, because identical software contains identical flaws. The chance of failure is reduced by using at least two different types of each of

1755-437: The shore, with an elevation of at least 5 feet (1.5 m) above sea level. For additional protection, they can be located at least 100 feet (30 m) away from flood plain areas. The two functions of redundancy are passive redundancy and active redundancy . Both functions prevent performance decline from exceeding specification limits without human intervention using extra capacity. Passive redundancy uses excess capacity to reduce

1800-399: The system decreases the probability of system failure according to the formula:- where: This formula assumes independence of failure events. That means that the probability of a component B failing given that a component A has already failed is the same as that of B failing when A has not failed. There are situations where this is unreasonable, such as using two power supplies connected to

1845-791: The transmissions using the Synchronous Digital Hierarchy protocols. The LTE is fed both an STM-1 at 155 Mbit/s and an STM-64 at 10 Gbit/s, resulting in a STM-64 and OC-192 protocol for transmission. The system is monitored using the Tyco Element Manager System, which are installed in Longyearbyen, Harstad and at Telenor's Network Operations Center in Fornebu . The system can be extended to 2,500 Gbit/s on each cable, by employing all pairs and adding additional wavelengths. The Svalbard undersea cable system connecting

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1890-471: The venture. Telenor changed its opinion in the following weeks and agreed to press forward on 18 November. The invitation to tender was issued on 21 December, with a deadline of 3 February. Bringing the line out from Andøya was selected because it is the only trawler -free area along the Norwegian coast north of Trondheim . The tender deadline was extended to 25 February. The bids showed the possibility of laying

1935-508: Was completed on 25 July. Permission for the installations on Svalbard was granted on 17 June. Cable-laying started on 21 July and lasted until 15 August. The work set a world record 1,671-meter (5,482 ft) deep plow. The work was carried out using the cable-laying vessels Cable Innovator and Maersk Recorder . Segment 1 was spliced on 1 August and Segment 2 was spliced on 13 August. Any costs exceeding US$ 40 million were covered by Telenor Svalbard, who levied it on other users on Svalbard over

1980-404: Was enacted to reduce confusion over the organisation's function and to clarify that its status as a government body. Space Norway is a related Norwegian space company that was established during 2014. Its mission statement is to own and/or lease space infrastructure and to make investments in space-related activities. While it operates as a commercial limited liability company, Space Norway

2025-421: Was established as the Norwegian Space Centre in 1987 in conjunction with Norway's decision to join the European Space Agency (ESA). It functions as an agency of the Norwegian Ministry of Trade and Industry . Its purpose is to conduct space activities that are of use to society and contribute to business development. The agency is also charged with safeguarding and promoting Norway's interests in relation to ESA,

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