Signals intelligence by alliances, nations and industries comprises signals intelligence (SIGINT) gathering activities by national and non-national entities; these entities are commonly responsible for communications security (COMSEC) as well.

Many US and allied SIGINT activities are considered Sensitive Compartmented Information (SCI) and carry the special security marking "HANDLE THROUGH COMINT CHANNELS ONLY", which is abbreviated as the suffix CCO to the security classification. SECRET SIGINT material would be marked (S-CCO). For exceptionally sensitive TOP SECRET material, there may be an additional codeword, such as (TS-CCO-RABID).

UKUSA Agreement

SIGINT and security procedures are closely coordinated under what is called the UKUSA Community, which includes Australia, Canada, New Zealand, the United Kingdom, and the United States cooperating in a major SIGINT activity codenamed ECHELON. Of the UKUSA partners, NSA is the US element, Britain's is the Government Communications Headquarters (GCHQ), Canada's is the Communications Security Establishment and a few other small groups, Australia's is the Australian Signals Directorate, and New Zealand's is the Government Communications Security Bureau.

ECHELON

It is fair to say that there is something called ECHELON, and it is very large. There is no unclassified definition of what it really does, and there are conflicting unofficial reports on its capabilities and operations. Duncan Campbell is the source of much information, but many of his claims have been challenged by independent sources. It is a 2000 report, and his claims that NSA has published no details of its operations is not the case in 2007. Another extensive report is that of the European Parliament in 2001. Campbell himself refined his definitions a year later. His "strict" definition of ECHELON is that it is a satellite interception component of the partners of the UKUSA Agreement. Even among the UKUSA members, according to Campbell, there may be other satellite interception stations not called ECHELON, probably in Australia and possibly in Great Britain.

It is generally accepted that ECHELON is a cooperative system, principally among the UKUSA Agreement partners, to intercept satellite, microwave, and other communications around the world, searching for information of interest to its members. The geographic distribution of the members allows much more effective worldwide coverage. This article does not replace the separate ECHELON Wikipedia article, but will complement it.

Campbell cites Jeffrey Richelson as defining, in the 4th edition of The American Intelligence Establishment, an "official" list of "third party" participants in ECHELON (or perhaps the UKUSA SIGINT alliance) as Norway, Denmark, Germany, Italy, Greece, Turkey, Austria, Japan, South Korea, and Thailand. Campbell further indicated that US payments to Norway and Denmark were stopped in 1992, and those countries intended to do their own satellite interception.

There are also conflicting reports about the relationship, if any, between ECHELON and US government warrantless monitoring wanted by the George W. Bush administration. Many reports focus on ECHELON's capability to intercept signals transmitted through free space, such as microwave and communications satellites. Given that much of the world's communications have moved to optical fiber cables, which are difficult but not impossible to intercept.

Much ECHELON specification is based on clues, such as noting the geographic location of various large satellite receiving antennas, then plotting the vertical and horizontal coordinates of the parabolic "dish" of the antenna. These can be correlated with the known positions of communications satellites to project that the antenna is intended to receive the signals of a particular satellite.

Other countries may be cooperating with the UKUSA countries, including Ireland and Switzerland. There are also conflicting reports about France cooperating with ECHELON, but also operating an independent capability.

Confirmation of ECHELON Two internal NSA newsletters from January 2011 and July 2012, published as part of the Snowden-revelations by the website The Intercept on August 3, 2015, for the first time confirmed that NSA used the codeword ECHELON and provided some details about the scope of the program: ECHELON was part of an umbrella program codenamed FROSTING, which was established by the NSA in 1966 to collect and process data from communications satellites. FROSTING had two sub-programs: TRANSIENT: for intercepting of Soviet satellites ECHELON: for intercepting of Intelsat satellites A first satellite ground station for the ECHELON collection program was built in 1971 at a military firing and training center near Yakima, Washington. The facility, which was codenamed JACKKNIFE, became fully operational in May 1973 and was connected with NSA headquarters at Fort Meade by a 75-baud secure teletype orderwire channel.The Northwest Passage, Yakima Research Station (YRS) newsletter: Volume 2, Issue 1, January 2011 & Volume 3, Issue 7, July 2012.

NATO

Communications and data exchange electronics are intended to be interoperable among NATO members, although not all countries will share sensitive data. Tactical information usually will be shared.

ASEAN and related groups

The Association of Southeast Asian Nations (ASEAN) original member states consisting of Indonesia, Malaysia, the Philippines, Singapore, and Thailand. Where the collective fear of communism had paved the way for the International Intelligence Cooperation (IIC) and subsequent structures found within the organization. After the end of the Cold War, former Soviet-align nations joining would shift the focus of the IIC from an anti-communist role to a counter-terrorism role. The subsequent nations include Brunei, Laos, Vietnam, Cambodia, Myanmar, which joined long before the creation of the IIC

Given Singapore's small but potent military, it made basing arrangements in Singapore, in Malaysia and the Philippines. Thailand and Malaysia have a good record working together against the Communist Party of Malaysia.

For some years, the ASEAN countries have held annual intelligence summits. It is unclear, however, if intelligence ties preceded or followed the development of military relationships. The author poses the challenge, "Do arrangements such as ECHELON exist outside the relationships between "great" powers? Literature shows that broad relationships exist among regional powers for various reasons. In the case of ASEAN, states brought together to fight communist insurgency find that they can maximize security by cooperating in covert operations and intelligence sharing."

Technology has accelerated ASEAN intelligence cooperation. For example, Malaysia and Singapore jointly monitor the South China Sea electronically. It is reasonable to assume that the less sensitive aspects of SIGINT, such as Direction finding are part of that surveillance. Other sources include the Five Power Defence Arrangements (FPDA) of Australia, Great Britain, New Zealand, Singapore and Malaysia, which includes three members of the UKUSA alliance with strong national SIGINT organizations.

Spurred by terrorism concerns, the ASEAN states, in May 2002, agreed on an Action Plan that provided for enhanced cooperation in intelligence sharing and coordination of anti-terror laws. In August 2002, ASEAN and the United States issued a “Joint Declaration . . . to Combat International Terrorism," which was followed by an ASEAN Regional Forum (ARF) meeting on terrorism, to be jointly sponsored by Malaysia in the US. The US proposed that a regional counterterrorism training center be established in Malaysia. Accompanying the Anti-Terrorism Center is an intelligence-sharing agreement among Indonesia, the Philippines, Malaysia, Cambodia, and Thailand, a first meeting of which was held in Manila in January 2003. An obvious question, without a simple answer, is how much SIGINT capabilities these countries have.

Some of these countries are reluctant to get too close to the US, involving nationalist issues in the Philippines and Islamic parties in Malaysia and Indonesia. Singapore, among the regional nations, seems most comfortable in exchanging intelligence information with the US, especially receiving SIGINT in return for HUMINT. Singapore has established sharing between the US PACOM Joint Intelligence Center and Singapore's Joint Counterterrorism Center, and Singapore also is leading in accepting US goals for maritime security, with a Strategic Goods Control law in January 2003. That law made Singapore the first major port to meet US homeland security rules for cargo. Singapore wants more US X-ray equipment, and possibly MASINT sensors.

US relations to ASEAN or other groups may be more domestically acceptable, in countries suspicious of the US, than bilateral arrangements. There are obvious reasons for regional nations wanting US intelligence support, including SIGINT. Nevertheless, the eagerness of the US to help against Islamic groups strikes at local sensitivities.

Other coalitions

UN and other, often ad hoc international coalitions have no predefined SIGINT interoperability; establishing even basic communications interoperabilities is one of the first and most urgent tasks of any coalition.

National SIGINT

Australia

Australia's main organization is in the Australian Signals Directorate. It operates collection stations for multilateral and national use. Australia has systems interoperable with UKUSA, and ECHELON.

Canada

Canada has the Communications Security Establishment and several other groups, especially military tactical groups. Canada has systems interoperable with NATO nations, UKUSA, and ECHELON.

China

China's main SIGINT effort is in the Technical Department, or Third Department of the General Staff Department of the Central Military Commission, with additional capabilities, primarily domestic, in the Ministry of State Security (MSS). SIGINT stations, therefore, are scattered through the country, for domestic as well as international interception. Prof. Desmond Ball, of the Australian National University, described the largest stations as

the main Technical Department SIGINT net control station on the northwest outskirts of Beijing large complex near Lake Kinghathu in the extreme northeast corner of China

Some Western analyses of the third department claim it maintains a staff of more than 130,000, though this figure cannot be independently confirmed.Capability of the People’s Republic of China to Conduct Cyber Warfare and Computer Network Exploitation Northrop Grumman Corporation page 31

Cuba

While Cuba had traditionally been a Soviet client, it both has been developing indigenous capabilities, including equipment design and manufacture, as well as having Chinese-operated stations on its soil. Within the Cuban intelligence ministry, a Counter-Electronic Warfare Department was established in 1997, at the same level as the Technical Department and the Foreign Intelligence Department. In 1992, a tactically oriented Counter-Electronic Warfare Department was created. The national intelligence organization also runs electronic warfare and SIGINT for the Air Force and Navy.

Russia and China, at various times, have operated or are operating intercept stations in Cuba, as well as Cuban-operated facilities. The largest and best-known, Lourdes SIGINT Station, was shut down by Russia in 2001, along with the Russian station at Cam Ranh Bay, Vietnam. Four ground stations (q.v.) are in Cuba, two of which are operated by China.

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