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116-475: The AMPRNet (AMateur Packet Radio Network) or Network 44 is used in amateur radio for packet radio and digital communications between computer networks managed by amateur radio operators . Like other amateur radio frequency allocations , an IP range of 44.0.0.0 / 8 was provided in 1981 for Amateur Radio Digital Communications (a generic term) and self-administered by radio amateurs. In 2001, undocumented and dual-use of 44.0.0.0 / 8 as

232-466: A call sign on the air to legally identify the operator or station. In some countries, the call sign assigned to the station must always be used, whereas in other countries, the call sign of either the operator or the station may be used. In certain jurisdictions, an operator may also select a "vanity" call sign although these must also conform to the issuing government's allocation and structure used for Amateur Radio call signs. Some jurisdictions require

348-641: A network telescope began, recording the spread of the Code Red II worm in July 2001. In mid-2019, part of IPv4 range was sold off for conventional use, due to IPv4 address exhaustion . Beginning on 1 May 1978, the Canadian authorities allowed radio amateurs on the 1.25-meter band (220 MHz) to use packet radio , and later in 1978 announced the "Amateur Digital Radio Operator's Certificate". Discussion on digital communication amateur radio modes , using

464-557: A router hosted at the University of California, San Diego . This forwarding router was originally named mirrorshades.ucsd.edu and later gw.ampr.org or " AmprGW ". By 1996 higher-speed 56k modems briefly had greater throughput than was possible to forward via the "mirrorshades" central reflector router and back again. Only IP addresses with an active Domain Name System (DNS) entry under ampr.org are passed by

580-587: A UPS store address. On 22 June 2012, 29 September 2015, and 18 September 2017, filings were made listing the company officers as: In 2011, the American Registry for Internet Numbers approved a request to change the registration of the whole 44/8 network block from an individual contact, to the "Amateur Radio Digital Communications" non-profit company. Activities were to "conserve scarce AMPRNet Internet protocol resources, and to educate networks users on how to efficiently utilize these resources as

696-456: A US citizen may operate under reciprocal agreements in Canada, but not a non-US citizen holding a US license. Many people start their involvement in amateur radio on social media or by finding a local club. Clubs often provide information about licensing, local operating practices, and technical advice. Newcomers also often study independently by purchasing books or other materials, sometimes with

812-441: A club or organization for a period of time before a higher class of license can be acquired. A reciprocal licensing agreement between two countries allows bearers of an amateur radio license in one country under certain conditions to legally operate an amateur radio station in the other country without having to obtain an amateur radio license from the country being visited, or the bearer of a valid license in one country can receive

928-464: A club or organization generally requires that an individual with a current and valid amateur radio license who is in good standing with the telecommunications authority assumes responsibility for any operations conducted under the club license or club call sign. A few countries may issue special licenses to novices or beginners that do not assign the individual a call sign but instead require the newly licensed individual to operate from stations licensed to

1044-846: A country. For example, the peak envelope power limits for the highest available license classes in a few selected countries are: 2.25  kW in Canada; 1.5 kW in the United States; 1.0 kW in Belgium, Luxembourg , Switzerland, South Africa and New Zealand; 750 W in Germany; 500 W in Italy; 400 W in Australia, India, and the United Kingdom; and 150 W in Oman . Subnetwork A subnetwork , or subnet ,

1160-639: A decade. In 1981, Hank Magnuski obtained the class A 44 / 8 netblock of 16.7 million IP addresses for amateur radio users worldwide. This was prior to Internet flag day (1 January 1983) when the ARPANET Network Control Protocol (NCP) was replaced by the Transmission Control Protocol (TCP). The initial name used by Jon Postel in RFC   790 was the "Amateur Radio Experiment Net". Originally

1276-619: A fee to obtain such a vanity call sign; in others, such as the UK, a fee is not required and the vanity call sign may be selected when the license is applied for. The FCC in the U.S. discontinued its fee for vanity call sign applications in September 2015, but replaced it as $ 35 in 2022. Call sign structure as prescribed by the ITU consists of three parts which break down as follows, using the call sign ZS1NAT as an example: Many countries do not follow

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1392-516: A few years the public Internet made these solutions obsolete. The ROSE system today is maintained by the Open Source FPAC Linux project. The AMPRNet is connected by wireless links and Internet tunnels. Due to the bandwidth limitations of the radio spectrum , 300 bit/s is normally used on HF, while VHF and UHF links are usually 1,200 bit/s to 9,600 bit/s. Mass-produced Wi-Fi access points equipment on 2.4 GHz and 5 GHz

1508-561: A given period of time. In addition to contests, a number of amateur radio operating award schemes exist, sometimes suffixed with "on the Air", such as Summits on the Air , Islands on the Air, Worked All States and Jamboree on the Air . Amateur radio operators may also act as citizen scientists for propagation research and atmospheric science . Radio transmission permits are closely controlled by nations' governments because radio waves propagate beyond national boundaries, and therefore radio

1624-410: A larger organization. Subnets may be arranged logically in a hierarchical architecture, partitioning an organization's network address space into a tree-like routing structure, or other structures, such as meshes. Computers participating in an IP network have at least one network address . Usually, this address is unique to each device and can either be configured automatically by a network service with

1740-642: A limiting factor. As in IPv4, subnetting in IPv6 is based on the concepts of variable-length subnet masking (VLSM) and the Classless Inter-Domain Routing methodology. It is used to route traffic between the global allocation spaces and within customer networks between subnets and the Internet at large. A compliant IPv6 subnet always uses addresses with 64 bits in the host identifier. Given

1856-457: A national licensing process and may instead require prospective amateur radio operators to take the licensing examinations of a foreign country. In countries with the largest numbers of amateur radio licensees, such as Japan, the United States, Thailand, Canada, and most of the countries in Europe, there are frequent license examinations opportunities in major cities. Granting a separate license to

1972-432: A nuisance. The use of "ham" meaning "amateurish or unskilled" survives today sparsely in other disciplines (e.g. "ham actor"). The amateur radio community subsequently began to reclaim the word as a label of pride, and by the mid-20th century it had lost its pejorative meaning. Although not an acronym or initialism, it is often written as "HAM" in capital letters. The many facets of amateur radio attract practitioners with

2088-472: A number after to indicate the political region; prefix CY indicates geographic islands. Prefix VA1 or VE1 is Nova Scotia , VA2 / VE2 is Quebec , VA3 / VE3 is Ontario , VA4 / VE4 is Manitoba , VA5 / VE5 is Saskatchewan , VA6 / VE6 is Alberta , VA7 / VE7 is British Columbia , VE8 is the Northwest Territories , VE9 is New Brunswick , VY0

2204-548: A planned upgrading to 10 Gigabit Ethernet with a passive optical tap , in order to provide finer timestamping and avoid packet loss . By July 2018, the replacement 10 Gigabit Ethernet infrastructure, using an optical splitter and Endace capture card, was operational. The archived intermittent captures for 2001‒2008 were 657 gigabytes . The archived pcap captures from 2008‒2012 were 192 terabytes of data uncompressed. In January 2012, five weeks of recent data were 5.5 terabytes uncompressed. Beginning on 22 March 2012,

2320-409: A pool of at least 350. To pass, 26 of the 35 questions must be answered correctly. The Extra Class exam has 50 multiple choice questions (drawn randomly from a pool of at least 500), 37 of which must be answered correctly. The tests cover regulations, customs, and technical knowledge, such as FCC provisions, operating practices, advanced electronics theory, radio equipment design, and safety. Morse Code

2436-446: A separate entry in the routing tables of each connected router, subnetting increases routing complexity. However, by careful design of the network, routes to collections of more distant subnets within the branches of a tree hierarchy can be aggregated into a supernetwork and represented by single routes. An IPv4 subnet mask consists of 32 bits; it is a sequence of ones ( 1 ) followed by a block of zeros ( 0 ). The ones indicate bits in

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2552-436: A separate license and a call sign in another country, both of which have a mutually-agreed reciprocal licensing approvals. Reciprocal licensing requirements vary from country to country. Some countries have bilateral or multilateral reciprocal operating agreements allowing hams to operate within their borders with a single set of requirements. Some countries lack reciprocal licensing systems. Others use international bodies such as

2668-634: A service to the entire Internet community" initiated "in the second half of 2012 by the President via communications with American Registry for Internet Numbers (ARIN)". Plans included "the issuance of grants and other financial support to educational institutions , foundations and other organizations. [...] expected to commence in 2013 via a joint effort of the three founding Directors [...]". During December 2017 Kantor announced his retirement from University of California San Diego . Re-stated (changed) articles of incorporation for

2784-455: A specification of network and broadcast addresses is not necessary. The design of the IPv6 address space differs significantly from IPv4. The primary reason for subnetting in IPv4 is to improve efficiency in the utilization of the relatively small address space available, particularly to enterprises. No such limitations exist in IPv6, as the large address space available, even to end-users, is not

2900-583: A student scholarship in the name of Alan Turing and honouring Brian Kantor. In May 2021, ARDC provided a one-off grant of $ 1.6 million to the Massachusetts Institute of Technology amateur radio club (W1MX) to save and rebuild the radome on top of the MIT Green Building (building 54) . In November 2021, ARDC awarded a five-year grant, for a total of $ 1.3 million , to support US-based activities around Amateur Radio on

3016-402: A subdivided network. For example, a / 24 network can be divided into sixteen usable / 28 networks. Each broadcast address, i.e. *.15 , *.31 , …, *.255 , reduces only the host count in each subnets. The number of subnets available and the number of possible hosts in a network may be readily calculated. For instance, the 192.168.5.0 / 24 network may be subdivided into

3132-400: A subnet are acceptable for host addressing. The all-zeroes address is reserved as the subnet-router anycast address. The subnet router anycast address is the lowest address in the subnet, so it looks like the “network address”. If a router has multiple subnets on the same link, then it has multiple subnet router anycast addresses on that link. The first and last address in any network or subnet

3248-411: A tunnel to a central router, which routes between the 44 network and the rest of the Internet using static routing tables updated by volunteers. As of October 2011 experimentation had moved beyond these centrally controlled static solutions, to dynamic configurations provided by Peer to Peer VPN systems such as n2n , and ZeroTier . The allocation plan agreed in late-1986 reserved half of

3364-404: A unique identifying call sign , which must be used in all transmissions. Amateur operators must hold an amateur radio license which is obtained by passing a government test demonstrating adequate technical radio knowledge and legal knowledge of the host government's radio regulations. Radio amateurs are limited to a specific set of frequency bands, the amateur radio bands, allocated throughout

3480-551: A wide range of interests. Many amateurs begin with a fascination with radio communication and then combine other personal interests to make pursuit of the hobby rewarding. Some of the focal areas amateurs pursue include radio contesting , radio propagation study, public service communication , technical experimentation , and computer networking . Hobbyist radio enthusiasts employ a variety of transmission methods for interaction . The primary modes for vocal communications are frequency modulation (FM) and single sideband (SSB). FM

3596-717: A year in the national capital and can be inordinately bureaucratic (for example in India) or challenging because some amateurs must undergo difficult security approval (as in Iran ). Currently, only Yemen and North Korea do not issue amateur radio licenses to their citizens. Some developing countries, especially those in Africa, Asia, and Latin America , require the payment of annual license fees that can be prohibitively expensive for most of their citizens. A few small countries may not have

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3712-411: Is Nunavut , VY1 is Yukon , VY2 is Prince Edward Island , VO1 is Newfoundland , and VO2 is Labrador . CY is for amateurs operating from Sable Island (CY0) or St. Paul Island (CY9). Special permission is required to access either of these: from Parks Canada for Sable and Coast Guard for St. Paul. The last two or three letters of the call signs are typically the operator's choice (upon completing

3828-440: Is a logical subdivision of an IP network . The practice of dividing a network into two or more networks is called subnetting . Computers that belong to the same subnet are addressed with an identical group of its most-significant bits of their IP addresses . This results in the logical division of an IP address into two fields: the network number or routing prefix , and the rest field or host identifier . The rest field

3944-503: Is an identifier for a specific host or network interface. The routing prefix may be expressed as the first address of a network, written in Classless Inter-Domain Routing (CIDR) notation, followed by a slash character ( / ), and ending with the bit-length of the prefix. For example, 198.51.100.0 / 24 is the prefix of the Internet Protocol version 4 network starting at the given address, having 24 bits allocated for

4060-406: Is divided into two logical parts, the network prefix and the host identifier . All hosts on a subnet have the same network prefix. This prefix occupies the most-significant bits of the address. The number of bits allocated within a network to the prefix may vary between subnets, depending on the network architecture. The host identifier is a unique local identification and is either a host number on

4176-660: Is done by volunteer coordinators with the proviso "we do not provide the same level of response as a commercial organisation." These addresses can possibly be made routable over the Internet if fully coordinated with the volunteer administrators. Radio amateurs wanting to request IP addresses within the AMPRNet should visit the AMPRNet Portal. Since the 1990s most packets within the 44 / 8 range were arranged to transit via an IP tunnel using IP in IP encapsulation to/from

4292-604: Is in the Turks and Caicos Islands, VP6xxx is on Pitcairn Island, VP8xxx is in the Falklands, and VP9xxx is in Bermuda. Online callbooks or call sign databases can be browsed or searched to find out who holds a specific call sign. An example of an online callbook is QRZ.com . Non-exhaustive lists of famous people who hold or have held amateur radio call signs have also been compiled and published. Many jurisdictions (but not in

4408-589: Is maintained on their website at [1] . Information on applying for a grant is at [2] . Amateur radio The amateur radio service ( amateur service and amateur-satellite service ) is established by the International Telecommunication Union (ITU) through the Radio Regulations . National governments regulate technical and operational characteristics of transmissions and issue individual station licenses with

4524-520: Is no longer tested in the U.S. Once the exam is passed, the FCC issues an Amateur Radio license which is valid for ten years. Studying for the exam is made easier because the entire question pools for all license classes are posted in advance. The question pools are updated every four years by the National Conference of VECs. Prospective amateur radio operators are examined on understanding of

4640-639: Is now being used on nearby amateur frequencies to provide much faster links as HSMM or hinternet . Since it is based on IP, the AMPRNet supports the same transport and application protocols as the rest of the Internet, though there are regulatory restrictions on encryption and third-party traffic. The AMPRNet is composed of a series of subnets throughout the world. Portions of the network have point-to-point radio links to adjacent nodes, while others are completely isolated. Geographically dispersed radio subnets can be connected using an IP tunnel between sites with Internet connectivity. Many of these sites also have

4756-466: Is of international concern. Both the requirements for and privileges granted to a licensee vary from country to country, but generally follow the international regulations and standards established by the International Telecommunication Union and World Radio Conferences . All countries that license citizens to use amateur radio require operators to display knowledge and understanding of key concepts, usually by passing an exam. The licenses grant hams

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4872-522: Is recognized for its superior audio quality, whereas SSB is more efficient for long-range communication under limited bandwidth conditions. Radiotelegraphy using Morse code , also known as "CW" from " continuous wave ", is the wireless extension of landline (wired) telegraphy developed by Samuel Morse and dates to the earliest days of radio. Although computer-based (digital) modes and methods have largely replaced CW for commercial and military applications, many amateur radio operators still enjoy using

4988-419: Is similar to Voice over IP (VoIP), but augments two-way radio communications rather than telephone calls. EchoLink using VoIP technology has enabled amateurs to communicate through local Internet-connected repeaters and radio nodes, while IRLP has allowed the linking of repeaters to provide greater coverage area. Automatic link establishment (ALE) has enabled continuous amateur radio networks to operate on

5104-692: Is the Wireless Institute of Australia , formed in 1910; other notable societies are the Radio Society of Great Britain , the American Radio Relay League , Radio Amateurs of Canada , Bangladesh NGOs Network for Radio and Communication , the New Zealand Association of Radio Transmitters and South African Radio League . ( See Category:Amateur radio organizations ) An amateur radio operator uses

5220-408: Is the bitmask that, when applied by a bitwise AND operation to any IP address in the network, yields the routing prefix. Subnet masks are also expressed in dot-decimal notation like an IP address. For example, the prefix 198.51.100.0 / 24 would have the subnet mask 255.255.255.0 . Traffic is exchanged between subnets through routers when the routing prefixes of the source address and

5336-684: Is typically found in the 70 cm (420–450 MHz) wavelength range, though there is also limited use on 33 cm (902–928 MHz), 23 cm (1240–1300 MHz) and shorter. These requirements also effectively limit the signal range to between 20 and 60 miles (30–100 km). Linked repeater systems, however, can allow transmissions of VHF and higher frequencies across hundreds of miles. Repeaters are usually located on heights of land or on tall structures, and allow operators to communicate over hundreds of miles using hand-held or mobile transceivers . Repeaters can also be linked together by using other amateur radio bands , landline , or

5452-619: Is valid only in the country where it is issued or in another country that has a reciprocal licensing agreement with the issuing country. In some countries, an amateur radio license is necessary in order to purchase or possess amateur radio equipment. Amateur radio licensing in the United States exemplifies the way in which some countries award different levels of amateur radio licenses based on technical knowledge: three sequential levels of licensing exams (Technician Class, General Class, and Amateur Extra Class) are currently offered, which allow operators who pass them access to larger portions of

5568-500: Is written as 255.255.255.0 . The modern standard form of specification of the network prefix is CIDR notation, used for both IPv4 and IPv6. It counts the number of bits in the prefix and appends that number to the address after a slash (/) character separator. This notation was introduced with Classless Inter-Domain Routing (CIDR). In IPv6 this is the only standards-based form to denote network or routing prefixes. For example,

5684-609: The 44.192 / 10 block had been allocated to amateur radio areas for the outer space - amateur radio satellite service, to roaming , Oceania , Antarctica , the Arctic , Italy for Centro Italiano Sperimentazione ed Attività Radiantistiche (CisarNet) Germany for Stuttgart / Tübingen , Eppstein , plus the Germany/pan-European Highspeed Amateur-radio Multimedia NETwork (HAMNET). Paul Vixie stated after

5800-479: The American Registry for Internet Numbers registry stated that a request for the transfer of IP addresses had been received and reviewed in accordance with ARIN policy. On 18 July 2019, the designation recorded by Internet Assigned Numbers Authority was altered from " 044 / 8 Amateur Radio Digital Communications" to " 044 / 8 Administered by ARIN ". On 18 July 2019, there was a sale of 44.192.0.0 / 10 address space to Amazon Technologies Inc, which

5916-580: The Center for Applied Internet Data Analysis at the San Diego Supercomputer Center . On 15 July 2001 the network monitoring of 44.0.0.0 / 8 traffic recorded the spread of the Code Red II worm. Prior to July 2001, the project had been logging unsolicited TCP SYN packets destined for IP addresses within 44.0.0.0 / 8 ; and after 19 July 2001 full incoming IP header logging took place. The 44 / 8 IP address block

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6032-705: The Defense Advanced Research Projects Agency (DARPA). In May 2017, the Center for Applied Internet Data Analysis provided a new server for the AMPRNet gateway, in a different building. As of mid-2017 a passive monitoring configuration was in use, involving a network switch with port mirroring set to duplicate the incoming packets being seen by the AMPRNet gateway to the UCSD network telescope capture server. The project funding proposal for "Sustainable Tools for Analysis and Research on Darknet Unsolicited Traffic" (STARDUST) specified

6148-661: The Dynamic Host Configuration Protocol (DHCP), manually by an administrator, or automatically by the operating system with stateless address autoconfiguration . An address fulfills the functions of identifying the host and locating it on the network in destination routing. The most common network addressing architecture is Internet Protocol version 4 (IPv4), but its successor, IPv6 , has been increasingly deployed since approximately 2006. An IPv4 address consists of 32 bits. An IPv6 address consists of 128 bits. In both architectures, an IP address

6264-724: The Internet . Amateur radio satellites can be accessed, some using a hand-held transceiver ( HT ), even, at times, using the factory "rubber duck" antenna. Hams also use the moon , the aurora borealis , and the ionized trails of meteors as reflectors of radio waves. Hams can also contact the International Space Station (ISS) because many astronauts are licensed as amateur radio operators. Amateur radio operators use their amateur radio station to make contacts with individual hams as well as participate in round-table discussion groups or "rag chew sessions" on

6380-548: The Internet . Amateur radio is officially represented and coordinated by the International Amateur Radio Union (IARU), which is organized in three regions and has as its members the national amateur radio societies which exist in most countries. According to an estimate made in 2011 by the American Radio Relay League (the American national amateur radio society), two million people throughout

6496-421: The Internet protocol suite and 44 / 8 IPv4 addresses followed subsequently. By 1988, one thousand assignments of address space had been made. As of December 2009 approximately 1% of inbound traffic volume to the 44/8 network was legitimate radio amateur traffic that could be routed onwards, with the remaining 2‒100 gigabyte per day of Internet background noise being diverted and logged by

6612-534: The University of California San Diego (UCSD) internet telescope for research purposes. By 2016, the European-based High-speed Amateur-radio Multimedia NETwork (HAMNET) offered a multi-megabit Internet Protocol network with 4,000 nodes, covering central Europe. The use of the Internet protocols TCP/IP on amateur (ham) radio occurred early in Internet history , preceding the public Internet by over

6728-402: The all ones host address, i.e. the last address within a network, for broadcast transmission to all hosts on the link. The first subnet obtained from subnetting a larger network has all bits in the subnet bit group set to zero. It is therefore called subnet zero . The last subnet obtained from subnetting a larger network has all bits in the subnet bit group set to one. It is therefore called

6844-418: The all-ones subnet . The IETF originally discouraged the production use of these two subnets. When the prefix length is not available, the larger network and the first subnet have the same address, which may lead to confusion. Similar confusion is possible with the broadcast address at the end of the last subnet. Therefore, reserving the subnet values consisting of all zeros and all ones on the public Internet

6960-482: The high frequency bands with global coverage. Other modes, such as FSK441 using software such as WSJT , are used for weak signal modes including meteor scatter and moonbounce communications. Fast scan amateur television has gained popularity as hobbyists adapt inexpensive consumer video electronics like camcorders and video cards in PCs . Because of the wide bandwidth and stable signals required, amateur television

7076-410: The packet filter for forwarding. By 19 August 1999 daily encapsulated IP in IP traffic was ~100 kilobits per second , peaking to 0.14 megabits per second . During mid-2000, the majority of unique IP addresses seen on the University of California, San Diego connection from CERFnet began with the 44 prefix, except for 17% of IP addresses which did not. In mid-2009 the mirrorshades server

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7192-444: The radio spectrum , but within these bands are allowed to transmit on any frequency using a variety of voice, text, image, and data communications modes. This enables communication across a city, region, country, continent, the world, or even into space. In many countries, amateur radio operators may also send, receive, or relay radio communications between computers or transceivers connected to secure virtual private networks on

7308-574: The "Amateur Radio Digital Communications" non-profit were signed on 13 December 2017, and filed on 17 December 2017. In May 2019, Kantor signed an agreement extending UCSD/CAIDA's use of Amprnet addresses for data collection until 31 July 2023. Brian Kantor died in November 2019. In February/March 2020, the Center for Networked Systems (CNS) of the University of California, San Diego (UCSD) received $ 225,000, given by ARDC to allow financial endowment of

7424-686: The Amateur Radio spectrum and more desirable (shorter) call signs. An exam, authorized by the Federal Communications Commission (FCC), is required for all levels of the Amateur Radio license. These exams are administered by Volunteer Examiners, accredited by the FCC-recognized Volunteer Examiner Coordinator (VEC) system. The Technician Class and General Class exams consist of 35 multiple-choice questions, drawn randomly from

7540-558: The CAIDA network telescope. In April 2009 the upstream rate limiting was removed, increasing the number of packets reaching the network telescope. At the end of 2012, seaport.caida.org was the network telescope data capture server with thor.caida.org used for near real-time data access. As of 2016, the 44/8 network was receiving backscatter from Denial-of-Service attacks (DoS) each measuring ~226 packets per second ( mean peak average) totalling 37 terabytes per month. Support

7656-524: The CW mode—particularly on the shortwave bands and for experimental work, such as Earth–Moon–Earth communication , because of its inherent signal-to-noise ratio advantages. Morse, using internationally agreed message encodings such as the Q code , enables communication between amateurs who speak different languages. It is also popular with homebrewers and in particular with "QRP" or very-low-power enthusiasts, as CW-only transmitters are simpler to construct, and

7772-452: The IPv4 network 192.0.2.0 with the subnet mask 255.255.255.0 is written as 192.0.2.0 / 24 , and the IPv6 notation 2001:db8:: / 32 designates the address 2001:db8:: and its network prefix consisting of the most significant 32 bits. In classful networking in IPv4, before the introduction of CIDR, the network prefix could be directly obtained from the IP address, based on its highest-order bit sequence. This determined

7888-589: The ITU convention for the numeral. In the United Kingdom the original calls G0xxx, G2xxx, G3xxx, G4xxx, were Full (A) License holders along with the last M0xxx full call signs issued by the City & Guilds examination authority in December 2003. Additional Full Licenses were originally granted to (B) Licenses with G1xxx, G6xxx, G7xxx, G8xxx and 1991 onward with M1xxx call signs. The newer three-level Intermediate License holders are assigned 2E0xxx and 2E1xxx, and

8004-754: The International Space Station (ARISS-USA). In January 2022, the Internet Archive received a grant of $ 0.9 million for assembling a Digital Library of Amateur Radio and Communications (DLARC). Internet Archive began the project in earnest in September 2022, and began seeking contributions of material in October. By November, 2022 the library had grown to 25,000 items. In January 2023 the library held over 51,000 items including more than 3,300 books and magazines available via controlled digital lending. An updated list of ARDC grants

8120-503: The Isle of Man, "GJ" & "MJ" are Jersey and "GU" & "MU" are Guernsey. Intermediate licence call signs are slightly different. They begin 2#0 and 2#1 where the # is replaced with the country letters as above. For example "2M0" and "2M1" are Scotland, "2W0" and "2W1" are Wales and so on. The exception however is for England. The letter "E" is used, but only in intermediate-level call signs. For example "2E0" & "2E1" are used whereas

8236-461: The Organization of American States to facilitate licensing reciprocity. When traveling abroad, visiting amateur operators must follow the rules of the country in which they wish to operate. Some countries have reciprocal international operating agreements allowing hams from other countries to operate within their borders with just their home country license. Other host countries require that

8352-581: The RF spectrum, usually allowing choice of an effective frequency for communications across a local, regional, or worldwide path. The shortwave bands, or HF , are suitable for worldwide communication, and the VHF and UHF bands normally provide local or regional communication, while the microwave bands have enough space, or bandwidth , for amateur television transmissions and high-speed computer networks . In most countries, an amateur radio license grants permission to

8468-428: The UK & Europe) may issue specialty vehicle registration plates to licensed amateur radio operators. The fees for application and renewal are usually less than the standard rate for specialty plates. In most administrations, unlike other RF spectrum users, radio amateurs may build or modify transmitting equipment for their own use within the amateur spectrum without the need to obtain government certification of

8584-552: The United Kingdom and Australia, have begun requiring a practical assessment in addition to the written exams in order to obtain a beginner's license, which they call a Foundation License. In most countries, an operator will be assigned a call sign with their license. In some countries, a separate "station license" is required for any station used by an amateur radio operator. Amateur radio licenses may also be granted to organizations or clubs. In some countries, hams were allowed to operate only club stations. An amateur radio license

8700-435: The above example by moving 2 bits from the host part to the network prefix to form four smaller subnets each one quarter of the previous size. IPv4 uses specially designated address formats to facilitate recognition of special address functionality. The first and the last subnets obtained by subnetting a larger network have traditionally had a special designation and, early on, special usage implications. In addition, IPv4 uses

8816-531: The address size of 128 bits, it therefore has a /64 routing prefix. Although it is technically possible to use smaller subnets, they are impractical for local area networks based on Ethernet technology, because 64 bits are required for stateless address autoconfiguration . The Internet Engineering Task Force recommends the use of / 127 subnets for point-to-point links, which have only two hosts. IPv6 does not implement special address formats for broadcast traffic or network numbers, and thus all addresses in

8932-496: The address space ( 44.0 / 9 or ~8 million addresses) for use within United States territory and ( 44.128 / 9 , the remaining ~8 million addresses) for the rest of the world. After the sale of 44.192.0.0 / 10 in 2019, the remaining Internet protocol (IP) addresses are the 44.0.0.0 / 9 for USA subnets and 44.128.0.0 / 10 subnet for the rest of the world, available to any licensed amateur radio operator. The IP address management and assigning of addresses

9048-443: The address used for the network prefix and the trailing block of zeros designates that part as being the host identifier. The following example shows the separation of the network prefix and the host identifier from an address ( 192.0.2.130 ) and its associated / 24 subnet mask ( 255.255.255.0 ). The operation is visualized in a table using binary address formats. The result of the bitwise AND operation of IP address and

9164-763: The air. Some join in regularly scheduled on-air meetings with other amateur radio operators, called " nets " (as in "networks"), which are moderated by a station referred to as "Net Control". Nets can allow operators to learn procedures for emergencies, be an informal round table, or cover specific interests shared by a group. Amateur radio operators, using battery- or generator-powered equipment, often provide essential communications services when regular channels are unavailable due to natural disaster or other disruptive events . Many amateur radio operators participate in radio contests, during which an individual or team of operators typically seek to contact and exchange information with as many other amateur radio stations as possible in

9280-442: The amateur link layer protocol AX.25 carried several competing higher level protocols, with TCP/IP a minority due to the complexity of the configuration and the high protocol overhead . Very few systems operated over HF for this reason. One approach for 1,200/9,600-baud VHF/UHF operation emerged as TCP/IP over ROSE (Radio Amateur Telecommunications Society "RATS" Open Systems Environment, based on X.25 CCITT standard). Within just

9396-513: The basic Foundation License holders are granted call signs M3xxx, M6xxx or M7xxx. Instead of using numbers, in the UK the second letter after the initial 'G' or 'M' identifies the station's location; for example, a call sign G7OOE becomes GM7OOE and M0RDM becomes MM0RDM when that license holder is operating a station in Scotland. Prefix "GM" & "MM" are Scotland, "GW" & "MW" are Wales, "GI" & "MI" are Northern Ireland, "GD" & "MD" are

9512-446: The call signs beginning G or M for foundation and full licenses never use the "E". In the United States, for non-vanity licenses, the numeral indicates the geographical district the holder resided in when the license was first issued. Prior to 1978, US hams were required to obtain a new call sign if they moved out of their geographic district. In Canada, call signs start with VA, VE, VY, VO, and CY. Call signs starting with 'V' end with

9628-427: The class (A, B, C) of the address and therefore the subnet mask. Since the introduction of CIDR, however, the assignment of an IP address to a network interface requires two parameters, the address and a subnet mask. Given an IPv4 source address, its associated subnet mask, and the destination address, a router can determine whether the destination is on a locally connected network or a remote network. The subnet mask of

9744-501: The classroom to teach English, map skills, geography, math, science, and computer skills. The term "ham" was first a pejorative term used in professional wired telegraphy during the 19th century, to mock operators with poor Morse code -sending skills (" ham-fisted "). This term continued to be used after the invention of radio and the proliferation of amateur experimentation with wireless telegraphy; among land- and sea-based professional radio operators, "ham" amateurs were considered

9860-573: The committee and ARRL board of directors were working on guidelines for semi-automatic digital stations, with the proposals passed to the Federal Communications Commission . On 6 October 2011 a Californian non-profit company was founded with the name of "Amateur Radio Digital Communications", and recorded by the State of California on 11 October 2011 with an address of "5663 Balboa Avenue, Suite 432, San Diego, California—

9976-443: The concept of being good stewards of the space . An Amateur Radio Digital Communications committee was formed to offer advice on digital standards to the American Radio Relay League (ARRL) board of directors, following a meeting in 1981. The original working name was the "ARRL Ad Hoc Committee on Digital Communication", abbreviated to "digital committee". During the mid-1980s, the committee had been meeting twice per year: during

10092-492: The destination address differ. A router serves as a logical or physical boundary between the subnets. The benefits of subnetting an existing network vary with each deployment scenario. In the address allocation architecture of the Internet using CIDR and in large organizations, efficient allocation of address space is necessary. Subnetting may also enhance routing efficiency, or have advantages in network management when subnets are administratively controlled by different entities in

10208-486: The destination is not needed, and is generally not known to a router. For IPv6, however, on-link determination is different in detail and requires the Neighbor Discovery Protocol (NDP). IPv6 address assignment to an interface carries no requirement of a matching on-link prefix and vice versa, with the exception of link-local addresses . Since each locally connected subnet must be represented by

10324-764: The early 20th century. The First Annual Official Wireless Blue Book of the Wireless Association of America , produced in 1909, contains a list of amateur radio stations. This radio callbook lists wireless telegraph stations in Canada and the United States, including 89 amateur radio stations. As with radio in general, amateur radio was associated with various amateur experimenters and hobbyists. Amateur radio enthusiasts have significantly contributed to science , engineering , industry, and social services . Research by amateur operators has founded new industries, built economies, empowered nations, and saved lives in times of emergency. Ham radio can also be used in

10440-408: The equipment. Licensed amateurs can also use any frequency in their bands (rather than being allocated fixed frequencies or channels) and can operate medium-to-high-powered equipment on a wide range of frequencies so long as they meet certain technical parameters including occupied bandwidth, power, and prevention of spurious emission . Radio amateurs have access to frequency allocations throughout

10556-399: The following four / 26 subnets. The highlighted two address bits become part of the network number in this process. The remaining bits after the subnet bits are used for addressing hosts within the subnet. In the above example, the subnet mask consists of 26 bits, making it 255.255.255.192, leaving 6 bits for the host identifier. This allows for 62 host combinations (2 −2). In general,

10672-423: The help of a mentor, teacher, or friend. In North America, established amateurs who help newcomers are often referred to as "Elmers", as coined by Rodney Newkirk, W9BRD, within the ham community. In addition, many countries have national amateur radio societies which encourage newcomers and work with government communications regulation authorities for the benefit of all radio amateurs. The oldest of these societies

10788-822: The human ear-brain signal processing system can pull weak CW signals out of the noise where voice signals would be totally inaudible. A similar "legacy" mode popular with home constructors is amplitude modulation (AM), pursued by many vintage amateur radio enthusiasts and aficionados of vacuum tube technology. Demonstrating a proficiency in Morse code was for many years a requirement to obtain an amateur license to transmit on frequencies below 30 MHz. Following changes in international regulations in 2003, countries are no longer required to demand proficiency. The United States Federal Communications Commission , for example, phased out this requirement for all license classes on 23 February 2007. Modern personal computers have encouraged

10904-570: The key concepts of electronics, radio equipment, antennas, radio propagation , RF safety, and the radio regulations of the government granting the license. These examinations are sets of questions typically posed in either a short answer or multiple-choice format. Examinations can be administered by bureaucrats , non-paid certified examiners, or previously licensed amateur radio operators. The ease with which an individual can acquire an amateur radio license varies from country to country. In some countries, examinations may be offered only once or twice

11020-417: The license holder to own, modify, and operate equipment that is not certified by a governmental regulatory agency. This encourages amateur radio operators to experiment with home-constructed or modified equipment. The use of such equipment must still satisfy national and international standards on spurious emissions . Amateur radio operators are encouraged both by regulations and tradition of respectful use of

11136-585: The licensing test, the ham writes three most-preferred options). Two-letter call sign suffixes require a ham to have already been licensed for 5 years. Call signs in Canada can be requested with a fee. Also, for smaller geopolitical entities, the numeral may be part of the country identification. For example, VP2xxx is in the British West Indies, which is subdivided into VP2Exx Anguilla, VP2Mxx Montserrat, and VP2Vxx British Virgin Islands. VP5xxx

11252-416: The local network or an interface identifier. This addressing structure permits the selective routing of IP packets across multiple networks via special gateway computers, called routers , to a destination host if the network prefixes of origination and destination hosts differ, or sent directly to a target host on the local network if they are the same. Routers constitute logical or physical borders between

11368-487: The middle of the year, and again at the annual Computer Networking conference. In September 1987, the committee recommended the list of frequencies that would be used in North America for packet radio and digital communications. In January 1988, the committee held a meeting to standardise AX.25 version 3. In March 1988, the "Packet Radio Frequency Recommendations" were published by the committee. During early 1993

11484-443: The network prefix, and the remaining 8 bits reserved for host addressing. Addresses in the range 198.51.100.0 to 198.51.100.255 belong to this network, with 198.51.100.255 as the subnet broadcast address . The IPv6 address specification 2001:db8:: / 32 is a large address block with 2 addresses, having a 32-bit routing prefix. For IPv4, a network may also be characterized by its subnet mask or netmask , which

11600-489: The number of available hosts on a subnet is 2 −2, where h is the number of bits used for the host portion of the address. The number of available subnets is 2 , where n is the number of bits used for the network portion of the address. There is an exception to this rule for 31-bit subnet masks, which means the host identifier is only one bit long for two permissible addresses. In such networks, usually point-to-point links , only two hosts (the endpoints) may be connected and

11716-809: The overall total collected by the UCSD Network Telescope stood at 3.25 petabytes (uncompressed), stored across 129,552 hourly files. Users of the collected data up to 2012 are requested to acknowledge that "Support for Backscatter Datasets and the UCSD Network Telescope is provided by Cisco Systems , Limelight Networks , the US Department of Homeland Security , the National Science Foundation , DARPA , Digital Envoy , and CAIDA Members." The original Class A network allocation for amateur radio

11832-892: The privilege to operate in larger segments of the radio frequency spectrum, with a wider variety of communication techniques, and with higher power levels relative to unlicensed personal radio services (such as CB radio , FRS , and PMR446 ), which require type-approved equipment restricted in mode, range, and power. Amateur licensing is a routine civil administrative matter in many countries. Amateurs therein must pass an examination to demonstrate technical knowledge, operating competence, and awareness of legal and regulatory requirements, in order to avoid interfering with other amateurs and other radio services. A series of exams are often available, each progressively more challenging and granting more privileges: greater frequency availability, higher power output, permitted experimentation, and, in some countries, distinctive call signs. Some countries, such as

11948-663: The raw hourly compressed pcap traces from 2003‒2012 were transferred to the National Energy Research Scientific Computing Center (NERSC) for long-term storage and research data archiving . This data migration of 104.66 tebibytes took one week at a sustained rate of 1.5 gigabits per second via the Energy Sciences Network (ESnet). For the 2012‒2017 period, 2.85 petabytes of data was collected (1.3 petabyte compressed). As of 31 December 2017,

12064-430: The sale of IP address space that "ampr.org can make better use of money than IP space in fulfilling its nonprofit mission, at this stage of the game ." Doug Barton, a former manager of Internet Assigned Numbers Authority , said the "reaction that we're seeing now is 100% predictable ... that doesn't change anything about my opinion that the sale itself was totally reasonable, done by reasonable people, and in keeping with

12180-497: The spectrum to use as little power as possible to accomplish the communication. This is to minimise interference or EMC to any other device. Although allowable power levels are moderate by commercial standards, they are sufficient to enable global communication. Lower license classes usually have lower power limits; for example, the lowest license class in the UK (Foundation licence) has a limit of 10 W. Power limits vary from country to country and between license classes within

12296-423: The subnet mask is the network prefix 192.0.2.0 . The host part, which is 130 , is derived by the bitwise AND operation of the address and the ones' complement of the subnet mask. Subnetting is the process of designating some high-order bits from the host part as part of the network prefix and adjusting the subnet mask appropriately. This divides a network into smaller subnets. The following diagram modifies

12412-441: The subnets, and manage traffic between them. Each subnet is served by a designated default router but may consist internally of multiple physical Ethernet segments interconnected by network switches . The routing prefix of an address is identified by the subnet mask , written in the same form used for IP addresses. For example, the subnet mask for a routing prefix that is composed of the most-significant 24 bits of an IPv4 address

12528-442: The use of digital modes such as radioteletype (RTTY) which previously required cumbersome mechanical equipment. Hams led the development of packet radio in the 1970s, which has employed protocols such as AX.25 and TCP/IP . Specialized digital modes such as PSK31 allow real-time, low-power communications on the shortwave bands but have been losing favor in place of newer digital modes such as FT8 . Radio over IP , or RoIP,

12644-509: The visiting ham apply for a formal permit, or even a new host country-issued license, in advance. The reciprocal recognition of licenses frequently not only depends on the involved licensing authorities, but also on the nationality of the bearer. As an example, in the US, foreign licenses are recognized only if the bearer does not have US citizenship and holds no US license (which may differ in terms of operating privileges and restrictions). Conversely,

12760-645: The world are regularly involved with amateur radio. About 830,000 amateur radio stations are located in IARU Region 2 (the Americas) followed by IARU Region 3 (South and East Asia and the Pacific Ocean) with about 750,000 stations. A significantly smaller number, about 400,000, are located in IARU Region 1 (Europe, Middle East, CIS , Africa). The origins of amateur radio can be traced to the late 19th century, but amateur radio as practised today began in

12876-512: Was made in the 1970s, and recorded in September 1981, which consisted of ~16 million IP addresses. As of 18 July 2019, the lower 75% of the 44 / 8 block (~12 million addresses) remained for amateur radio usage, with the upper 25% ( 44.192 / 10 , ~4 million IP address) having been sold. Owing to IPv4 address exhaustion , by 2016 the 44 / 8 block was worth over $ 100 million . The 44 / 8 routing prefix aggregation stopped being advertised on 4 June 2019. John Curran , CEO of

12992-421: Was recommended, reducing the number of available subnets by two for each subnetting. This inefficiency was removed, and the practice was declared obsolete in 1995 and is only relevant when dealing with legacy equipment. Although the all-zeros and the all-ones host values are reserved for the network address of the subnet and its broadcast address , respectively, in systems using CIDR all subnets are available in

13108-413: Was stated to have "high value to research". Capture data for August 2001, using data compression and retaining only IP headers was 0.5 gigabyte per hour. In 2002 the block was 0.4% of all internet IPv4 address space. By September 2003, traffic was 0.75 terabytes per month and costing $ 2,500 per month for bandwidth. In October 2004 Limelight Networks began to sponsor the internet transit costs of

13224-485: Was supplied by Cisco Systems under a University Research Board (URB) grant. The project was funded by an Advanced Networking Infrastructure and Research (ANIR) award, and Computer and Network Systems (CNS) award from the National Science Foundation (NSF); the United States Department of Homeland Security (DHS); and Network Modeling & Simulation (NMS) / Next Generation Internet Program (NGI) of

13340-400: Was the highest bidder, for use by Amazon Web Services . AMPRNet subsequently consisted of 44.0 / 9 , and 44.128 / 10 , with no plans to sell any more address space. The aspiration expressed by those involved in the sale was that money be held by a non-profit 501(c)(3) organization for the advancement of amateur radio. The sale raised over $ 50 million. Prior to sale, addresses in

13456-602: Was upgraded and replaced after about ~1,100 days uptime . A funding proposal in 2010 raised the possibility that "The legitimate traffic is also a potential research resource". Beginning in February 2001, as part of backscatter research and the CAIDA/UCSD network telescope project, the whole of the 44 / 8 address block was being advertised via the border gateway protocol (BGP) as a passive honeypot for Internet background noise and backscatter collection, based in

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