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134-420: Hayes was a major brand in the modem market from the introduction of the original 300 bit/s Smartmodem in 1981. They remained a major vendor throughout the 1980s, periodically introducing models with higher throughput . Their competition through this period was primarily from two other high-end vendors, USRobotics and Telebit , while other companies mostly sold into niches or were strictly low-end offerings. In

268-525: A Singapore -based venture capital firm. In 1997 they merged with Access Beyond , a builder of ISP rack-mount modems and terminal servers , and changed the company name again, this time to Hayes Communications . The merger was primarily a way to take the company public. The stock started crashing over the next year, from around US$ 12 in early 1998 to pennies in October, when they once again filed for Chapter 11 protection. No new funding could be found, and in 1999

402-580: A natural monopoly . The FCC controlled telephone rates and imposed other restrictions under Title II to limit the profits of AT&T and ensure nondiscriminatory pricing. In the 1960s, the FCC began allowing other long-distance companies, namely MCI, to offer specialized services. In the 1970s, the FCC allowed other companies to expand offerings to the public. A lawsuit in 1982 led by the Justice Department after AT&T underpriced other companies, resulted in

536-597: A standard desktop telephone to rest on top, was announced in April 1981. It was known simply as the Smartmodem . The Smartmodem was the first modem integrating complete control over the phone line, and that allowed it to be used in exactly the same fashion with any computer. Hayes originally had big plans for the form factor, referring to it as the Hayes Stack and intending to release a range of products that could be stacked beside

670-509: A "Cadillac of modems", using high-quality components, an extruded aluminum case, and an acrylic front panel with a number of LED indicators. As the modem market expanded, competitors quickly copied the Hayes command set and often the Hayes industrial design as well. To compete with Hayes on price, early competitors manufactured modems using low-cost components that were often unreliable. Hayes quickly gained

804-540: A "chief" that is appointed by the chair of the commission. Bureaus process applications for licenses and other filings, analyze complaints, conduct investigations, develop and implement regulations, and participate in hearings . The FCC has twelve staff offices. The FCC's offices provide support services to the bureaus. The FCC leases space in the Sentinel Square III building in northeast Washington, D.C. Prior to moving to its new headquarters in October 2020,

938-498: A Bell-supplied Data Access Arrangement (DAA) which the user rented for a monthly fee. To fill in dead-times in the modem sales, they also took on part work doing electronics assembly for other companies. Business picked up quickly, and by January 1978 they had quit their jobs at National Data to form their own company, D.C. Hayes Associates . In its first year, the new company sold $ 125,000 worth of product (equivalent to $ 583,929 in 2023). Sales further improved in early 1979 with

1072-463: A communication system will be limited by a huge number of factors. Some of these are described below: The maximum achievable throughput (the channel capacity) is affected by the bandwidth in hertz and signal-to-noise ratio of the analog physical medium. Despite the conceptual simplicity of digital information, all electrical signals traveling over wires are analog. The analog limitations of wires or wireless systems inevitably provide an upper bound on

1206-508: A different hardware design was needed for every computer bus , including Apple II , S-100, TRS-80 , and others. As modems became popular, users on these platforms began asking for designs as well. A solution to the cross-platform connection was to use the RS-232 serial port instead of the internal data bus; modems were serial devices in the end, and most computers included an RS-232 port or some variant. The trick would be how to send commands over

1340-471: A flood of companies like Supra Corporation and Zoom Telephonics . As speeds increased with the introduction of V.34 and V.90 , Hayes increasingly became a follower rather than a leader. By the mid-1990s their modems were also based on the Rockwell chipset and had little to distinguish themselves from other vendors. Oddly it was the Rockwell chipset that also re-standardized the various command sets back on

1474-464: A full 25-pin connector at all. In fact, there were very few pins that were guaranteed to work on all computers, mostly the data in and out, "ready" indications that said whether the modem or computer was operational, and sometimes flow-control pins. While it would have been possible to use some of these pins for the sort of command-switching they needed, this may not have been universally supported across all machines. Heatherington instead came up with

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1608-403: A gateway router supporting a populated class B subnet , handling 10 × 100 Mbit/s Ethernet channels, must examine 16 bits of address to determine the destination port for each packet. This translates into 81913 packets per second (assuming maximum data payload per packet) with a table of 2^16 addresses this requires the router to be able to perform 5.368 billion lookup operations per second. In

1742-424: A long time (sometimes considered infinity). For high duty cycle networks, this is likely to be the most accurate indicator of system performance. The maximum throughput is defined as the asymptotic throughput when the load (the amount of incoming data) is large. In packet switched systems where the load and the throughput always are equal (where packet loss does not occur), the maximum throughput may be defined as

1876-432: A network could demand any time it wanted from a Network affiliate . The second concerned artist bureaus. The networks served as both agents and employers of artists, which was a conflict of interest the report rectified. In assigning television stations to various cities after World War II , the FCC found that it placed many stations too close to each other, resulting in interference. At the same time, it became clear that

2010-680: A new Federal Communications Commission, including in it also the telecommunications jurisdiction previously handled by the Interstate Commerce Commission. Title II of the Communications Act focused on telecommunications using many concepts borrowed from railroad legislation and Title III contained provisions very similar to the Radio Act of 1927 . The initial organization of the FCC was effected July 17, 1934, in three divisions, Broadcasting, Telegraph, and Telephone. Each division

2144-491: A number of new commands prefixed by & (the ampersand) to the Smartmodem 2400. Other companies offering 2400 bit/s generally followed the same syntax. When Hayes moved to the Smartmodem 9600, they extended the set further, using the same syntax. However, by this time the other companies involved had introduced their own syntax; USR used an incompatible set of & -prefixed commands, Microcom used \ , and Telebit

2278-463: A number. The modem would normally start-up in command mode. The problem was how to move from mode to mode. One option would be to signal this using one of the many pins in the RS-232 cable. However, while the 25-pin connector on the modem side had more than enough pins for this purpose (even some meant for this purpose), the computer side often had far fewer pins connected and controllable, if it even used

2412-462: A renegotiation procedure. However, Express 96 both was late to market and lacked error correction , making it far less attractive than its competition. The design was generally unsuccessful, and for the first time Hayes lost cachet as the leader in modem design and manufacture. Hayes' slow entry into the high-speed market led to a fracturing of the command set. In order to set up the modem to accept or reject certain types of connections, Hayes had added

2546-634: A reputation for high quality, and for a time held a 50% market share. In 1982, at the Spring Comdex in Atlantic City, Hayes introduced the Bell 212 -compatible Smartmodem 1200 for $ 699, the first practical all-in-one 1200 bit/s Bell 212-compatible modem. The earlier design was redesignated the Smartmodem 300 . At the time, Hayes was one of the few modem companies with the capital and engineering wherewithal to develop entirely new modem architectures. However, this

2680-416: A short period of time; mathematically, this is the limit taken with respect to throughput as time approaches zero. This term is synonymous with instantaneous throughput . This number is useful for systems that rely on burst data transmission; however, for systems with a high duty cycle , this is less likely to be a useful measure of system performance. This value is the throughput averaged or integrated over

2814-491: A similar amount. Digital systems refer to the 'knee frequency', the amount of time for the digital voltage to rise from 10% of a nominal digital '0' to a nominal digital '1' or vice versa. The knee frequency is related to the required bandwidth of a channel, and can be related to the 3 db bandwidth of a system by the equation:   F 3 d B ≈ K / T r {\displaystyle \ F_{3dB}\approx K/T_{r}} Where Tr

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2948-410: A situation he found "perplexing". These efforts later were documented in a 2015 Harvard Case Study. In 2017, Christine Calvosa replaced Bray as the acting CIO of FCC. On January 4, 2023, the FCC voted unanimously to create a newly formed Space Bureau and Office of International Affairs within the agency, replacing the existing International Bureau. FCC chairwoman Jessica Rosenworcel explained that

3082-505: A smaller modem manufacturer, BizComp, who had filed a patent in 1980 but only received it in 1983. The patent covered the use of an escape sequence to switch between command and data mode, just like the Smartmodem. BizComp had already implemented the system in its modems in 1980, a year before the Smartmodem came to market. They offered a sliding scale of terms; an outright license was $ 2 million, but they would accept as little as $ 500,000 with additional per-unit fees. Hayes responded by licensing

3216-541: A strong niche by offering deep discounts to sysops . In 1987 Hayes responded with the Hayes Express 96 protocol, a 9600 bit/s protocol. It was sometimes referred to as the "Ping-Pong" protocol due to the way the modems could "ping-pong" the single high-speed link between the two ends on demand, in a fashion similar to the USR and Telebit protocols. The key improvement is that the channel could be switched very rapidly, without

3350-436: A worst-case scenario, where the payloads of each Ethernet packet are reduced to 100 bytes, this number of operations per second jumps to 520 billion. This router would require a multi-teraflop processing core to be able to handle such a load. Ensuring that multiple users can harmoniously share a single communications link requires some kind of equitable sharing of the link. If a bottleneck communication link offering data rate R

3484-645: Is capable of, or its "maximum performance" is what the user or designer is interested in. The term maximum throughput is frequently used when discussing end-user maximum throughput tests.   Maximum throughput is essentially synonymous to digital bandwidth capacity . Four different values are relevant in the context of "maximum throughput", used in comparing the 'upper limit' conceptual performance of multiple systems. They are 'maximum theoretical throughput', 'maximum achievable throughput', 'peak measured throughput', and 'maximum sustained throughput'. These values represent different quantities, and care must be taken that

3618-519: Is delivered per second to the application layer protocol. Dropped packets or packet retransmissions, as well as protocol overhead, are excluded. Because of that, the "goodput" is lower than the throughput. Technical factors that affect the difference are presented in the " goodput " article. Often, a block in a data flow diagram has a single input and a single output, and operate on discrete packets of information. Examples of such blocks are fast Fourier transform modules or binary multipliers . Because

3752-656: Is funded entirely by regulatory fees. It has an estimated fiscal-2022 budget of US $ 388 million. It has 1,482 federal employees as of July 2020. The FCC's mission, specified in Section One of the Communications Act of 1934 and amended by the Telecommunications Act of 1996 (amendment to 47 U.S.C. §151), is to "make available so far as possible, to all the people of the United States, without discrimination on

3886-523: Is in modeling point-to-point communication where (following Hockney) message latency T(N) is modeled as a function of message length N as T(N) = (M + N)/A where A is the asymptotic bandwidth and M is the half-peak length. As well as its use in general network modeling, asymptotic throughput is used in modeling performance on massively parallel computer systems, where system operation is highly dependent on communication overhead, as well as processor performance. In these applications, asymptotic throughput

4020-493: Is inserted after each frame. This corresponds to a maximum channel utilization of 1526 / (1526 + 12) × 100% = 99.22%, or a maximum channel use of 99.22 Mbit/s inclusive of Ethernet datalink layer protocol overhead in a 100 Mbit/s Ethernet connection. The maximum throughput or channel efficiency is then 1500 / (1526 + 12) = 97.5%, exclusive of the Ethernet protocol overhead. The throughput of

4154-435: Is more accurately reported taking into account format and specification overhead with best case assumptions. This number, like the closely related term 'maximum achievable throughput' below, is primarily used as a rough calculated value, such as for determining bounds on possible performance early in a system design phase. The asymptotic throughput (less formal asymptotic bandwidth ) for a packet-mode communication network

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4288-480: Is more often used instead. Federal Communications Commission The Federal Communications Commission ( FCC ) is an independent agency of the United States government that regulates communications by radio , television , wire, satellite , and cable across the United States. The FCC maintains jurisdiction over the areas of broadband access , fair competition , radio frequency use, media responsibility, public safety, and homeland security . The FCC

4422-477: Is practiced is an Ethernet network. In this case, the maximum throughput is the gross bit rate or raw bit rate. However, in schemes that include forward error correction codes (channel coding), the redundant error code is normally excluded from the throughput. An example in modem communication, where the throughput typically is measured in the interface between the Point-to-Point Protocol (PPP) and

4556-411: Is shared by "N" active users (with at least one data packet in queue), every user typically achieves a throughput of approximately R/N , if fair queuing best-effort communication is assumed. The maximum throughput is often an unreliable measurement of perceived bandwidth, for example the file transmission data rate in bits per seconds. As pointed out above, the achieved throughput is often lower than

4690-480: Is the 10% to 90% rise time, and K is a constant of proportionality related to the pulse shape, equal to 0.35 for an exponential rise, and 0.338 for a Gaussian rise. Computational systems have finite processing power and can drive finite current. Limited current drive capability can limit the effective signal to noise ratio for high capacitance links. Large data loads that require processing impose data processing requirements on hardware (such as routers). For example,

4824-408: Is the maximum system throughput (aggregate throughput) divided by the analog bandwidth and some measure of the system coverage area. Throughput over analog channels is defined entirely by the modulation scheme, the signal-to-noise ratio, and the available bandwidth. Since throughput is normally defined in terms of quantified digital data, the term 'throughput' is not normally used; the term 'bandwidth'

4958-424: Is the percentage of the net bit rate (in bit/s) of a digital communication channel that goes to the actually achieved throughput. For example, if the throughput is 70 Mbit/s in a 100 Mbit/s Ethernet connection, the channel efficiency is 70%. In this example, effectively 70 Mbit of data are transmitted every second. Channel utilization is instead a term related to the use of the channel, disregarding

5092-439: Is the value of the maximum throughput function, when the incoming network load approaches infinity , either due to a message size , or the number of data sources. As other bit rates and data bandwidths , the asymptotic throughput is measured in bits per second (bit/s) or (rarely) bytes per second (B/s), where 1 B/s is 8 bit/s. Decimal prefixes are used, meaning that 1 Mbit/s is 1000000 bit/s. Asymptotic throughput

5226-474: Is transmitting, the maximum throughput is often equivalent to or very near the physical data rate (the channel capacity ), since the channel utilization can be almost 100% in such a network, except for a small inter-frame gap. For example, the maximum frame size in Ethernet is 1526 bytes: up to 1500 bytes for the payload, eight bytes for the preamble, 14 bytes for the header, and 4 bytes for the trailer. An additional minimum interframe gap corresponding to 12 bytes

5360-447: Is used in Xu and Hwang model (more general than Hockney's approach) which includes the number of processors, so that both the latency and the asymptotic throughput are functions of the number of processors. The above values are theoretical or calculated. Peak measured throughput is throughput measured by a real, implemented system, or a simulated system. The value is the throughput measured over

5494-457: Is usually estimated by sending or simulating a very large message (sequence of data packets) through the network, using a greedy source and no flow control mechanism (i.e., UDP rather than TCP ), and measuring the network path throughput in the destination node. Traffic load between other sources may reduce this maximum network path throughput. Alternatively, a large number of sources and sinks may be modeled, with or without flow control, and

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5628-458: Is usually measured in bits per second (bit/s, sometimes abbreviated bps), and sometimes in packets per second (p/s or pps) or data packets per time slot . The system throughput or aggregate throughput is the sum of the data rates that are delivered over all channels in a network. Throughput represents digital Bandwidth (computing)bandwidth consumption. The throughput of a communication system may be affected by various factors, including

5762-686: The Broadcast Decency Enforcement Act of 2005 sponsored by then-Senator Sam Brownback , a former broadcaster himself, and endorsed by Congressman Fred Upton of Michigan who authored a similar bill in the United States House of Representatives . The new law stiffens the penalties for each violation of the Act. The Federal Communications Commission will be able to impose fines in the amount of $ 325,000 for each violation by each station that violates decency standards. The legislation raised

5896-470: The Georgia Institute of Technology in the mid-1970s to work at an early data communications company, National Data Corporation , a company that, among its many businesses, handled electronic money transfers and credit card authorizations. Hayes' job was to set up modem connections for NDC's customers. Hayes also worked for a time at Financial Data Sciences , which sold automated teller machines to

6030-859: The Time Independent Escape Sequence , or TIES, but it was not as robust as Heatherington's system and never became very successful. Hayes was not as fast as some other manufacturers to release modems that ran faster than 2400 bit/s, which opened the door for USRobotics (USR) and Telebit to meet market demand with faster products. Telebit was the fastest, running up to ~18,500 bit/s and maintaining higher speeds on noisy lines where other models would fall-back to lower speeds. They were also expensive and found mostly in professional settings, notably for Unix -running minicomputers for UUCP use where their protocol spoofing offered further speed improvements. USR's designs were simpler than Telebits and ran at "only" 9,600 bit/s, but carved out

6164-495: The United States Senate for five-year terms, except when filling an unexpired term. The U.S. president designates one of the commissioners to serve as chairman. No more than three commissioners may be members of the same political party . None of them may have a financial interest in any FCC-related business. Commissioners may continue serving until the appointment of their replacements. However, they may not serve beyond

6298-488: The breakup of the Bell System from AT&T. Beginning in 1984, the FCC implemented a new goal that all long-distance companies had equal access to the local phone companies' customers. Effective January 1, 1984, the Bell System's many member-companies were variously merged into seven independent "Regional Holding Companies", also known as Regional Bell Operating Companies (RBOCs), or "Baby Bells". This divestiture reduced

6432-480: The computer bus not only to exchange data between the computer and the modem, but command and status information as well. This allowed them to control the entire connection cycle, dialing the phone to start, and hanging up at the end. Such systems were available for large machines, especially the mainframes used by banks which had to automatically dial their branches for end-of-day updates. None of these systems were available for microcomputers, and Hayes' initial concept

6566-533: The savings and loan (S&L) market, modifying machines sold by larger companies to large banks with the branding of the smaller S&L. From this company, he learned the value of selling into niche markets the larger players ignored. Hayes was a computer hobbyist, and felt that modems would be highly compelling to users of the new 8-bit computers that would soon be known as home computers . However, existing modems were simply too expensive and difficult to use or be practical for most users. He felt that this market

6700-447: The 1 MHz PIC microcontrollers , which were available for only US$ 1 a piece. After six months of trying to get the modem working with the PIC, Heatherington gave up and demanded they use the 8 MHz Zilog Z8 instead, a US$ 10 part. Sirkis acquiesced, and a working prototype was soon complete. Hayes added a requirement of his own, that the modem be able to automatically detect what speed

6834-457: The 1960s All-Channel Receiver Act ), to make UHF viable against entrenched VHF stations. In markets where there were no VHF stations and UHF was the only TV service available, UHF survived. In other markets, which were too small to financially support a television station, too close to VHF outlets in nearby cities, or where UHF was forced to compete with more than one well-established VHF station, UHF had little chance for success. Denver had been

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6968-484: The Bell companies flexibility in terms of what to install at the user's site. Their attention turned to Asymmetric Digital Subscriber Line (ADSL), which ran over the existing wiring and did not block a telephone connection in the process. The end-user was offered much higher speeds while still being able to use existing phones, with the added "benefit" of helping tie the user to the telephone company's own ISP. Hayes, having bet

7102-731: The Cable Communications Policy Act of 1984, and made substantial modifications to Title VI in the Cable Television and Consumer Protection and Competition Act of 1992. Further modifications to promote cross-modal competition (telephone, video, etc.) were made in the Telecommunications Act of 1996, leading to the current regulatory structure. Broadcast television and radio stations are subject to FCC regulations including restrictions against indecency or obscenity. The Supreme Court has repeatedly held, beginning soon after

7236-522: The FCC a legal basis for imposing net neutrality rules (see below), after earlier attempts to impose such rules on an "information service" had been overturned in court. In 2005, the FCC formally established the following principles: To encourage broadband deployment and preserve and promote the open and interconnected nature of the public Internet, Consumers are entitled to access the lawful Internet content of their choice; Consumers are entitled to run applications and use services of their choice, subject to

7370-584: The FCC in the newly created post of associate general counsel/chief diversity officer. Numerous controversies have surrounded the city of license concept as the internet has made it possible to broadcast a single signal to every owned station in the nation at once, particularly when Clear Channel, now IHeartMedia , became the largest FM broadcasting corporation in the US after the Telecommunications Act of 1996 became law - owning over 1,200 stations at its peak. As part of its license to buy more radio stations, Clear Channel

7504-437: The FCC indicated that the public largely believed that the severe consolidation of media ownership had resulted in harm to diversity, localism, and competition in media, and was harmful to the public interest. David A. Bray joined the commission in 2013 as chief information officer and quickly announced goals of modernizing the FCC's legacy information technology (IT) systems, citing 200 different systems for only 1750 people

7638-545: The FCC leased space in the Portals building in southwest Washington, D.C. Construction of the Portals building was scheduled to begin on March 1, 1996. In January 1996, the General Services Administration signed a lease with the building's owners, agreeing to let the FCC lease 450,000 sq ft (42,000 m ) of space in Portals for 20 years, at a cost of $ 17.3 million per year in 1996 dollars. Prior to

7772-403: The FCC said that nearly 55 million Americans did not have access to broadband capable of delivering high-quality voice, data, graphics and video offerings. On February 26, 2015, the FCC reclassified broadband Internet access as a telecommunications service, thus subjecting it to Title II regulation, although several exemptions were also created. The reclassification was done in order to give

7906-459: The FCC's re-allocation map of stations did not come until April 1952, with July 1, 1952, as the official beginning of licensing new stations. Other FCC actions hurt the fledgling DuMont and ABC networks. American Telephone and Telegraph (AT&T) forced television coaxial cable users to rent additional radio long lines , discriminating against DuMont, which had no radio network operation. DuMont and ABC protested AT&T's television policies to

8040-510: The FCC, which regulated AT&T's long-line charges, but the commission took no action. The result was that financially marginal DuMont was spending as much in long-line charge as CBS or NBC while using only about 10 to 15 percent of the time and mileage of either larger network. The FCC's "Sixth Report & Order" ended the Freeze. It took five years for the US to grow from 108 stations to more than 550. New stations came on line slowly, only five by

8174-455: The Internet, cable services and wireless services has raised questions whether new legislative initiatives are needed as to competition in what has come to be called 'broadband' services. Congress has monitored developments but as of 2009 has not undertaken a major revision of applicable regulation. The Local Community Radio Act in the 111th Congress has gotten out of committee and will go before

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8308-554: The Portals, the FCC had space in six buildings at and around 19th Street NW and M Street NW. The FCC first solicited bids for a new headquarters complex in 1989. In 1991 the GSA selected the Portals site. The FCC had wanted to move into a more expensive area along Pennsylvania Avenue . In 1934, Congress passed the Communications Act , which abolished the Federal Radio Commission and transferred jurisdiction over radio licensing to

8442-411: The US consumer market. The whole model was based on end-to-end digital communications, and was thus limited to the speed of the long-distance carrier lines, either 56 or 64 kbit/s. The Bell companies were interested in deploying ISDN, but doing so required customer-end installations to make their conventional telephones work, which made the system unattractive for wide-scale deployment. Additionally,

8576-484: The United States accelerated an already ongoing shift in the FCC towards a decidedly more market-oriented stance. A number of regulations felt to be outdated were removed, most controversially the Fairness Doctrine in 1987. In terms of indecency fines, there was no action taken by the FCC on the case FCC v. Pacifica until 1987, about ten years after the landmark United States Supreme Court decision that defined

8710-470: The aggregate maximum network throughput measured (the sum of traffic reaching its destinations). In a network simulation model with infinite packet queues, the asymptotic throughput occurs when the latency (the packet queuing time) goes to infinity, while if the packet queues are limited, or the network is a multi-drop network with many sources, and collisions may occur, the packet-dropping rate approaches 100%. A well-known application of asymptotic throughput

8844-497: The amount of information that can be sent. The dominant equation here is the Shannon–Hartley theorem , and analog limitations of this type can be understood as factors that affect either the analog bandwidth of a signal or as factors that affect the signal-to-noise ratio. The bandwidth of wired systems can be in fact surprisingly narrow, with the bandwidth of Ethernet wire limited to approximately 1 GHz, and PCB traces limited by

8978-422: The basis of race, color, religion, national origin, or sex, rapid, efficient, nationwide, and world-wide wire and radio communication services with adequate facilities at reasonable charges." The act furthermore provides that the FCC was created "for the purpose of the national defense" and "for the purpose of promoting safety of life and property through the use of wire and radio communications." Consistent with

9112-572: The book value of AT&T by approximately 70%. The FCC initially exempted "information services" such as broadband Internet access from regulation under Title II. The FCC held that information services were distinct from telecommunications services that are subject to common carrier regulation. However, Section 706 of the Telecommunications Act of 1996 required the FCC to help accelerate deployment of "advanced telecommunications capability" which included high-quality voice, data, graphics, and video, and to regularly assess its availability. In August 2015,

9246-434: The channel. In a simplistic approach, channel efficiency can be equal to channel utilization assuming that acknowledge packets are zero-length and that the communications provider will not see any bandwidth relative to retransmissions or headers. Therefore, certain texts mark a difference between channel utilization and protocol efficiency. In a point-to-point or point-to-multipoint communication link, where only one terminal

9380-400: The characters flowing out from the computer to the modem were not simply additional data to be sent to the far end, but commands to be acted on. Hayes and the company's marketing manager Glenn Sirkis approached Heatherington with an outline for a new command-driven external modem. Several solutions to the command problem were studied, and in the end, Heatherington decided the only practical one

9514-426: The circuit-switched modem connection. In this case, the maximum throughput is often called net bit rate or useful bit rate. To determine the actual data rate of a network or connection, the " goodput " measurement definition may be used. For example, in file transmission, the "goodput" corresponds to the file size (in bits) divided by the file transmission time. The " goodput " is the amount of useful information that

9648-444: The commission in 1934 comprised the following seven members: The complete list of commissioners is available on the FCC website. Frieda B. Hennock (D-NY) was the first female commissioner of the FCC in 1948. The FCC regulates broadcast stations, repeater stations as well as commercial broadcasting operators who operate and repair certain radiotelephone , radio and television stations. Broadcast licenses are to be renewed if

9782-586: The company assets were liquidated. The brand name was purchased and revived by onetime rival Zoom Telephonics in July 1999. Zoom continues to use the Hayes name on some of their products. Throughput Network throughput (or just throughput , when in context) refers to the rate of message delivery over a communication channel in a communication network , such as Ethernet or packet radio . The data that these messages contain may be delivered over physical or logical links, or through network nodes . Throughput

9916-526: The company on a system that was never actually deployed, had no new products in the pipeline. In an attempt at diversification in January 1991 it had acquired most of the assets of local area network software developer Waterloo Microsystems Inc of Waterloo, Ontario and belatedly entered the operating system (OS) market in June 1991 with LANstep, a network OS for small offices, but this was subsequently abandoned in 1994 in

10050-442: The computer's serial port was set to when first powered on. This was not simple unless the modem "knew" what data were initially being sent, allowing it to time the bits and thereby guess the speed. Heatherington eventually suggested the use of a well-known character sequence for this purpose, recommending AT for "attention", which is prefixed on all commands. The new design, housed in an extruded aluminum case sized to allow

10184-475: The computer. In the end, only two non-modem devices were added to the line. The Hayes Stack Chronograph , an external real-time clock and the Transet 1000 , a printer buffer and primitive email box. Both of these items' sales were apparently dismal. Early advertising referred to the Smartmodem as the "Hayes Stack Smartmodem", but this naming convention was dropped a short time later. At the time of its introduction,

10318-414: The conversion, Congress established a federally sponsored DTV Converter Box Coupon Program for two free converters per household. The FCC regulates telecommunications services under Title II of the Communications Act of 1934. Title II imposes common carrier regulation under which carriers offering their services to the general public must provide services to all customers and may not discriminate based on

10452-427: The designated VHF channels, 2 through 13, were inadequate for nationwide television service. As a result, the FCC stopped giving out construction permits for new licenses in October 1948, under the direction of Chairman Rosel H. Hyde . Most expected this "Freeze" to last six months, but as the allocation of channels to the emerging UHF technology and the eagerly awaited possibilities of color television were debated,

10586-523: The early 1990s a number of greatly cost-reduced high-performance modems were released by competitors, notably the SupraFAXModem 14400 in 1992, which eroded price points in the market. Hayes was never able to respond effectively. The widespread introduction of ADSL and cable modems in the mid-1990s repeatedly drove the company in Chapter 11 protection before being liquidated in 1999. Dennis C. Hayes left

10720-421: The end of November 1952. The Sixth Report and Order required some existing television stations to change channels, but only a few existing VHF stations were required to move to UHF, and a handful of VHF channels were deleted altogether in smaller media markets like Peoria , Fresno , Bakersfield and Fort Wayne, Indiana to create markets which were UHF "islands." The report also set aside a number of channels for

10854-413: The end of the next session of Congress following term expiration. In practice, this means that commissioners may serve up to 1 + 1 ⁄ 2 years beyond the official term expiration listed above if no replacement is appointed. This would end on the date that Congress adjourns its annual session, generally no later than noon on January 3. The FCC is organized into seven bureaus, each headed by

10988-486: The end of the digital television transition. After delaying the original deadlines of 2006, 2008, and eventually February 17, 2009, on concerns about elderly and rural folk, on June 12, 2009, all full-power analog terrestrial TV licenses in the U.S. were terminated as part of the DTV transition , leaving terrestrial television available only from digital channels and a few low-power LPTV stations. To help U.S. consumers through

11122-405: The expected performance of a system. From a user perspective, this is often phrased as either "which device will get my data there most effectively for my needs?", or "which device will deliver the most data per unit cost?". Systems designers often select the most effective architecture or design constraints for a system, which drive its final performance. In most cases, the benchmark of what a system

11256-463: The face of stiff competition particularly from Novell NetWare . An effort was started to move into the market for ADSL and cable modems , but this was a multi-year effort during a period when USR increasingly took over what remained of the high-end modem market. They entered Chapter 11 protection in November 1994, exiting in October 1995 as Hayes Corp. after selling 49% of the company to Nortel and

11390-423: The fine ten times over the previous maximum of $ 32,500 per violation. The FCC has established rules limiting the national share of media ownership of broadcast radio or television stations. It has also established cross-ownership rules limiting ownership of a newspaper and broadcast station in the same market, in order to ensure a diversity of viewpoints in each market and serve the needs of each local market. In

11524-598: The first post-Freeze construction permits. KFEL (now KWGN-TV )'s first regular telecast was on July 21, 1952. In 1996, Congress enacted the Telecommunications Act of 1996 , in the wake of the breakup of AT&T resulting from the U.S. Department of Justice's antitrust suit against AT&T. The legislation attempted to create more competition in local telephone service by requiring Incumbent Local Exchange Carriers to provide access to their facilities for Competitive Local Exchange Carriers . This policy has thus far had limited success and much criticism. The development of

11658-457: The form of the FCC-approved "microcoupler": a small external box that connected to the internal modem card using a ribbon cable . In 1980, the company changed its name to Hayes Microcomputer Products . Although powerful, the internal modem was commercially impractical. Not only did it require special driver software that often meant it could only be used with a single terminal emulator , but

11792-435: The house floor with bi-partisan support, and unanimous support of the FCC. By passing the Telecommunications Act of 1996, Congress also eliminated the cap on the number of radio stations any one entity could own nationwide and also substantially loosened local radio station ownership restrictions. Substantial radio consolidation followed. Restrictions on ownership of television stations were also loosened. Public comments to

11926-413: The idea of using a rarely seen sequence of characters for this duty. Since these characters could be sent to the modem using the same two data pins that the port would need anyway, they could be sure that such a system would work on every computer. The sequence he decided on was +++ (three plus signs). When this was received from the computer, the modem would switch from data to command mode. Of course, it

12060-446: The identity of the customer or the content of the communication. This is similar to and adapted from the regulation of transportation providers (railroad, airline, shipping, etc.) and some public utilities. Wireless carriers providing telecommunications services are also generally subject to Title II regulation except as exempted by the FCC. The FCC regulates interstate telephone services under Title II. The Telecommunications Act of 1996

12194-428: The industry. A flurry of suits and countersuits followed. The bid to overturn the patent failed in 1986. Some time later, Hayes received permission to bring suits in federal court against infringers, and filed an initial suit against several major manufacturers, Everex, Ven-Tel, Omnitel and Prometheus Products . Competitors derisively termed it the "modem tax", and a number of manufacturers banded together and introduced

12328-625: The introduction of V.32 , the CCITT began the process of standardizing a slightly faster variant, the 14,400 bit/s V.32bis . During previous speed bumps, the large companies like Hayes and USR were generally the first to respond with new models. Not so in this case; shortly after V.32bis was ratified in 1991, Rockwell introduced a low-cost chipset supporting the new standard, along with similar V.32 and V.22bis (2400 bit/s) versions, all of which supported MNP, V.42bis and, optionally, 9600 bit/s V.29 fax modem capabilities. Their system

12462-512: The introduction of the 300 bit/s Micromodem 100 for S-100 bus computers and the Micromodem II for the Apple II. As a result of Bell having lost several key lawsuits related to the connection of unlicensed equipment to its telephone network, by 1978 it finally became legal to connect any FCC -approved system to the Bell network. To comply, Micromodems were supplied their own DAA-like connector in

12596-518: The largest U.S. city without a TV station by 1952. Senator Edwin Johnson (D-Colorado), chair of the Senate's Interstate and Foreign Commerce Committee , had made it his personal mission to make Denver the first post-Freeze station. The senator had pressured the FCC, and proved ultimately successful as the first new station (a VHF station) came on-line a remarkable ten days after the commission formally announced

12730-473: The limitations of the underlying physical medium, available processing power of the system components, end-user behavior, etc. When taking various protocol overheads into account, the useful rate of the data transfer can be significantly lower than the maximum achievable throughput; the useful part is usually referred to as goodput . Users of telecommunications devices, systems designers, and researchers into communication theory are often interested in knowing

12864-496: The market was already flooded with lower-cost modems. They then split their line into the Accura and Optima brands, offering the Accura as a low-cost model, although the feature sets were not that different between the two lines. Hayes eventually purchased two of their competitors, Practical Peripherals and Cardinal Technologies , turning them into low-cost brands in order to compete with

12998-447: The market. By 1982, the company was selling 140,000 modems a year, with sales of $ 12 million annually (equivalent to $ 37,886,897 in 2023). Heatherington retired from what was then a large company in 1984. The modem market in the 1970s was very simple and stagnant. Modems tended to sell at US$ 1 per baud. Hayes saw no need to be different—the original Hayes 300 baud modem sold for US$ 299 retail. At that price point, Hayes could build

13132-409: The maximum throughput. Also, the protocol overhead affects the perceived bandwidth. The throughput is not a well-defined metric when it comes to how to deal with protocol overhead. It is typically measured at a reference point below the network layer and above the physical layer. The simplest definition is the number of bits per second that are physically delivered. A typical example where this definition

13266-563: The minimum load in bit/s that causes the delivery time (the latency ) to become unstable and increase towards infinity. This value can also be used deceptively in relation to peak measured throughput to conceal packet shaping . Throughput is sometimes normalized and measured in percentage, but normalization may cause confusion regarding what the percentage is related to. Channel utilization , channel efficiency and packet drop rate in percentage are less ambiguous terms. The channel efficiency, also known as bandwidth utilization efficiency ,

13400-423: The modem market was fairly small, and competitors generally ignored the Smartmodem. But it was not long before hobbyists were able to combine the Smartmodem with new software to create the first real bulletin board systems (BBSes), which created significant market demand. The market grew rapidly in the mid-1980s, and as the Smartmodem was the only truly "universal" modem on the market, Hayes grew to take over much of

13534-486: The move was done to improve the FCC's "coordination across the federal government" and to "support the 21st-century satellite industry." The decision to establish the Space Bureau was reportedly done to improve the agency's capacity to regulate Satellite Internet access . The new bureau officially launched on April 11, 2023. The commissioners of the FCC are: The initial group of FCC commissioners after establishment of

13668-495: The negative effects of media concentration and consolidation on racial-ethnic diversity in staffing and programming. At these Latino town hall meetings, the issue of the FCC's lax monitoring of obscene and pornographic material in Spanish-language radio and the lack of racial and national-origin diversity among Latino staff in Spanish-language television were other major themes. President Barack Obama appointed Mark Lloyd to

13802-482: The newly emerging field of educational television , which hindered struggling ABC and DuMont 's quest for affiliates in the more desirable markets where VHF channels were reserved for non-commercial use. The Sixth Report and Order also provided for the "intermixture" of VHF and UHF channels in most markets; UHF transmitters in the 1950s were not yet powerful enough, nor receivers sensitive enough (if they included UHF tuners at all - they were not formally required until

13936-466: The objectives of the act as well as the 1999 Government Performance and Results Act (GPRA), the FCC has identified four goals in its 2018–22 Strategic Plan. They are: Closing the Digital Divide, Promoting Innovation, Protecting Consumers & Public Safety, and Reforming the FCC's Processes. The FCC is directed by five commissioners appointed by the president of the United States and confirmed by

14070-521: The original high-speed ones introduced by Hayes. As the Rockwell-based systems became more and more common, other companies, like AT&T, introduced new versions of their modem chip sets with identical commands. Rockwell had taken their commands from the V-series Smartmodems, so by the mid-90s the market was once again based largely on a "real" Hayes command set. Hayes realized that changes in

14204-541: The overall link is lower than or equal to the lowest bit rate. The lowest value link in the series is referred to as the bottleneck . This number is closely related to the channel capacity of the system, and is the maximum possible quantity of data that can be transmitted under ideal circumstances. In some cases this number is reported as equal to the channel capacity, though this can be deceptive, as only non-packetized systems (asynchronous) technologies can achieve this without data compression. Maximum theoretical throughput

14338-577: The passage of the Communications Act of 1934, that the inherent scarcity of radio spectrum allows the government to impose some types of content restrictions on broadcast license holders notwithstanding the First Amendment. Cable and satellite providers are also subject to some content regulations under Title VI of the Communications Act such as the prohibition on obscenity, although the limitations are not as restrictive compared to broadcast stations. The 1981 inauguration of Ronald Reagan as President of

14472-400: The patent outright for $ 2 million (equivalent to $ 5,143,000 in 2023). Hayes themselves also had a patent filing working its way through the system since 1981, although it mentioned the escape system and modes only in passing. Having obtained a license, they re-wrote their patent to include a lengthy section on the idea of a guard time, which the original Bizcomp patent lacked. They received

14606-399: The patent, 4,549,302 Modem With Improved Escape Sequence With Guard Time Mechanism , in October 1985. Hayes began sending bills to other manufacturers, charging 2% of the retail price per modem that followed the Hayes system, including those modems that had already been built and sold. This resulted in a number of companies launching a patent review, claiming the concept had long been used in

14740-466: The power of the FCC over indecent material as applied to broadcasting. After the 1990s had passed, the FCC began to increase its censorship and enforcement of indecency regulations in the early 2000s to include a response to the Janet Jackson " wardrobe malfunction " that occurred during the halftime show of Super Bowl XXXVIII . Then on June 15, 2006, President George W. Bush signed into law

14874-614: The report was the breakup of the National Broadcasting Company (NBC), which ultimately led to the creation of the American Broadcasting Company (ABC), but there were two other important points. One was network option time, the culprit here being the Columbia Broadcasting System (CBS). The report limited the amount of time during the day and at what times the networks may broadcast. Previously

15008-458: The rise of the Internet in the mid-1990s made point-to-point communications far less interesting. After dialing their local Internet service provider , the user could "call out" at high speed to services around the world, so the need for long-distance data calls was generally eliminated. As a result of this shift, there was no real need to limit the user to the speed of the long-distance lines, giving

15142-465: The same connection as the data. A few external modems already offered the ability to dial the phone by entering a phone number when the modem was first started, based on the idea that it could not be connected to a remote system when first powered up, so anything sent from the computer could (optionally) be interpreted as a command. The problem was sending a command to hang up, while the modem was already connected. There needed to be some way to indicate that

15276-413: The same definitions are used when comparing different 'maximum throughput' values. Each bit must carry the same amount of information if throughput values are to be compared. Data compression can significantly alter throughput calculations, including generating values exceeding 100% in some cases. If the communication is mediated by several links in series with different bit rates, the maximum throughput of

15410-900: The second half of 2006, groups such as the National Hispanic Media Coalition, the National Latino Media Council, the National Association of Hispanic Journalists, the National Institute for Latino Policy , the League of United Latin American Citizens (LULAC) and others held town hall meetings in California, New York and Texas on media diversity as its effects Latinos and minority communities. They documented widespread and deeply felt community concerns about

15544-435: The station meets the "public interest, convenience, or necessity". The FCC's enforcement powers include fines and broadcast license revocation (see FCC MB Docket 04-232). Burden of proof would be on the complainant in a petition to deny. The FCC first promulgated rules for cable television in 1965, with cable and satellite television now regulated by the FCC under Title VI of the Communications Act. Congress added Title VI in

15678-415: The telephone networks would eventually render the modem, in its current form, obsolete. As early as 1985 he started efforts to produce consumer-ready ISDN "modems", betting the company on ISDN becoming a widespread standard—which was widely believed at the time. By the early 1990s, this was a major focus of the company. However, unlike parts of Europe (mainly Germany) or Japan, ISDN simply never happened in

15812-412: The throughput. It counts not only with the data bits, but also with the overhead that makes use of the channel. The transmission overhead consists of preamble sequences, frame headers and acknowledge packets. The definitions assume a noiseless channel. Otherwise, the throughput would not be only associated with the nature (efficiency) of the protocol, but also to retransmissions resultant from the quality of

15946-459: The units of throughput are the reciprocal of the unit for propagation delay , which is 'seconds per message' or 'seconds per output', throughput can be used to relate a computational device performing a dedicated function such as an ASIC or embedded processor to a communications channel, simplifying system analysis. In wireless networks or cellular systems , the system spectral efficiency in bit/s/Hz/area unit, bit/s/Hz/site or bit/s/Hz/cell,

16080-528: Was based on setting a series of registers. All of these survived for some time into the early 1990s. Through the late 1980s and early 1990s, new standard high-speed modes were introduced by the CCITT . The first of these, V.32 , offered 9600 bit/s in both directions at the same time, whereas earlier high-speed protocols were high-speed in one direction only. In 1988 Hayes effectively abandoned their Express 96 protocol in favor of V.32, which along with MNP support

16214-547: Was built into the US$ 1199 Hayes V-series Smartmodem 9600 . In 1990 the company introduced the Smartmodem Ultra 96 , which offered both V.32 and Express 96 support, and added the new V.42bis error correction and compression system (in addition to MNP). V.32 modems remained fairly rare and expensive, although by 1990 third-party V.32 modems were available for approximately US$ 600. Almost immediately after

16348-441: Was forced to divest all TV stations. To facilitate the adoption of digital television, the FCC issued a second digital TV (DTV) channel to each holder of an analog TV station license. All stations were required to buy and install all new equipment ( transmitters , TV antennas, and even entirely new broadcast towers ), and operate for years on both channels. Each licensee was required to return one of their two channels following

16482-688: Was formed by the Communications Act of 1934 to replace the radio regulation functions of the previous Federal Radio Commission . The FCC took over wire communication regulation from the Interstate Commerce Commission . The FCC's mandated jurisdiction covers the 50 states, the District of Columbia , and the territories of the United States . The FCC also provides varied degrees of cooperation, oversight, and leadership for similar communications bodies in other countries in North America. The FCC

16616-473: Was heard. Disconnecting at the end of the session was also manual, with the user lifting the handset out of the coupler and hanging it up on the phone body in order to depress the hook switch and return the phone to the on-hook state and end the call. This was a straightforward and thus a popular solution; the Novation CAT was a popular modem of this type. Internal modems had the advantage that they could use

16750-546: Was introduced commercially in the SupraFAXModem 14400 , which went on to become a runaway bestseller. Soon there were hundreds of similar models on the market, and Rockwell's competitors also rushed in with similar chipsets of their own. Hayes was never able to re-establish itself as a market leader through this period. In the fall of 1991 they introduced the US$ 799 Smartmodem Ultra 144 which also supported Express 96, but by this point, Express 96 had little cachet and

16884-541: Was led by two of the seven commissioners, with the FCC chairman being a member of each division. The organizing meeting directed the divisions to meet on July 18, July 19, and July 20, respectively. In 1940, the Federal Communications Commission issued the "Report on Chain Broadcasting " which was led by new FCC chairman James Lawrence Fly (and Telford Taylor as general counsel). The major point in

17018-417: Was likely to be ignored by the larger modem vendors like IBM . At the time, modems generally came in two versions, external modems using an acoustic coupler for connection, and direct-connection modems used with minicomputers or mainframes . Acoustic couplers were entirely manual; the user picked up the phone's handset, dialed manually, and then pressed the handset into the coupler if a carrier frequency

17152-443: Was no exception; the company introduced its V.22bis Smartmodem 2400 at US$ 549 in 1985 (the 1200 bit/s Smartmodem also remained available at a lower price point). Competition drove prices rapidly downward, and by 1987 a clone 2400 bit/s modem was generally available for around US$ 250. After 1987, modems increasingly became a commodity item. In June 1983, Hayes and a number of other manufacturers were sent licensing demands by

17286-533: Was only a limited competitive advantage, since it was not long before companies offering Hayes "clones" introduced derivative 1200 bit/s models of their own. The 1200 bit/s market existed for a relatively short time; in 1984 the CCITT introduced the V.22bis standard for 2400 bit/s operation. This was the first time that the CCITT's standard predated Bell's introductions, avoiding compatibility issues that had plagued earlier standards. Modem companies quickly incorporated V.22bis into their product lines. Hayes

17420-407: Was possible that the computer would send this sequence for other reasons, for example, the sequence is contained within the text on this page, and likely would be in any document referring to modems. In order to filter out these "accidental" sequences, Heatherington's design only switched to command mode if the sequence was led and followed by a one-second pause, the guard time , in which no other data

17554-420: Was sent. In this case it could be safely assumed that the sequence was being sent deliberately by a user, as opposed to being buried in the middle of a data stream. With the basic idea outlined, Hayes and Sirkis gave Heatherington the go-ahead to build a prototype by adding a microcontroller to an otherwise lightly modified version of their existing 300 bit/s hardware. Sirkis was particularly interested in using

17688-463: Was the first major legislative reform since the 1934 act and took several steps to de-regulate the telephone market and promote competition in both the local and long-distance marketplace. The important relationship of the FCC and the American Telephone and Telegraph (AT&T) Company evolved over the decades. For many years, the FCC and state officials agreed to regulate the telephone system as

17822-411: Was to have the modem operate in two modes. In one, data mode , all data forwarded from the computer was modulated and sent over the connected telephone line as it was with any other modem. In the other, command mode , data forwarded from the computer would be interpreted as commands. In this way, the modem could be instructed by the computer to perform various operations, such as hang up the phone or dial

17956-405: Was to offer similar products into this market. Hayes started producing such a system in his kitchen in April 1977 with his friend and co-worker, Dale Heatherington . Their first product was the 80-103A , a 300 bit/s Bell 103 -compatible design for S-100 bus machines. At this time, it was illegal to connect any non-Bell hardware to the telephone network, so the 80-103A was designed to connect to

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