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123-811: FCoE transports Fibre Channel directly over Ethernet while being independent of the Ethernet forwarding scheme. The FCoE protocol specification replaces the FC0 and FC1 layers of the Fibre Channel stack with Ethernet. By retaining the native Fibre Channel constructs, FCoE was meant to integrate with existing Fibre Channel networks and management software. Traditionally, data centers used both Ethernet for TCP/IP networks and Fibre Channel for SANs , each having different and mostly incompatible interfaces/connections and interconnects/wiring and thus requires separate cabling/wiring and interconnects such as switching hardware for each. With

246-454: A datagram is called a packet or frame . Packet is used to describe the overall transmission unit and includes the preamble , start frame delimiter (SFD) and carrier extension (if present). The frame begins after the start frame delimiter with a frame header featuring source and destination MAC addresses and the EtherType field giving either the protocol type for the payload protocol or

369-515: A buffer on the switch in its entirety, its frame check sequence verified and only then the packet is forwarded. In modern network equipment, this process is typically done using application-specific integrated circuits allowing packets to be forwarded at wire speed . When a twisted pair or fiber link segment is used and neither end is connected to a repeater, full-duplex Ethernet becomes possible over that segment. In full-duplex mode, both devices can transmit and receive to and from each other at

492-455: A coaxial cable 0.375 inches (9.5 mm) in diameter, later called thick Ethernet or thicknet . Its successor, 10BASE2 , called thin Ethernet or thinnet , used the RG-58 coaxial cable. The emphasis was on making installation of the cable easier and less costly. Since all communication happens on the same wire, any information sent by one computer is received by all, even if that information

615-468: A complete data set – not to declare/measure global recessions according to quarterly GDP data. The seasonally adjusted PPP ‑weighted real GDP for the G20‑;zone, however, is a good indicator for the world GDP, and it was measured to have suffered a direct quarter on quarter decline during the three quarters from Q3‑2008 until Q1‑2009, which more accurately mark when

738-594: A consequence, FCoE is not routable at the IP layer and will not work across routed IP networks such as the Internet. Since classical Ethernet had no priority-based flow control , unlike Fibre Channel, FCoE required enhancements to the Ethernet standard to support a priority-based flow control mechanism (to reduce frame loss from congestion). The IEEE standards body added priorities in the data center bridging (dcb) Task Group. Fibre Channel required three primary extensions to deliver

861-478: A crisis of ideas in mainstream economics and within the economics profession, and call for a reshaping of both the economy, economic theory and the economics profession. They argue that such a reshaping should include new advances within feminist economics and ecological economics that take as their starting point the socially responsible, sensible and accountable subject in creating an economy and economic theories that fully acknowledge care for each other as well as

984-468: A dedicated Ethertype of 0x8914. In October 2003, Azul Technology developed early version and applied for a patent. In April 2007, the FCoE standardization activity started. In October 2007, the first public end-to-end FCoE demo occurred at Storage Network World including adapters from QLogic, switches from Nuova Systems, and storage from NetApp (none of the companies involved made any product announcements at

1107-576: A disproportionate share of defaults. The Economist wrote in July 2012 that the inflow of investment dollars required to fund the U.S. trade deficit was a major cause of the housing bubble and financial crisis: "The trade deficit, less than 1% of GDP in the early 1990s, hit 6% in 2006. That deficit was financed by inflows of foreign savings, in particular from East Asia and the Middle East. Much of that money went into dodgy mortgages to buy overvalued houses, and

1230-581: A doubling of network size. Once repeaters with more than two ports became available, it was possible to wire the network in a star topology . Early experiments with star topologies (called Fibernet ) using optical fiber were published by 1978. Shared cable Ethernet is always hard to install in offices because its bus topology is in conflict with the star topology cable plans designed into buildings for telephony. Modifying Ethernet to conform to twisted-pair telephone wiring already installed in commercial buildings provided another opportunity to lower costs, expand

1353-536: A greater number of nodes, and longer link distances, but retains much backward compatibility . Over time, Ethernet has largely replaced competing wired LAN technologies such as Token Ring , FDDI and ARCNET . The original 10BASE5 Ethernet uses a thick coaxial cable as a shared medium . This was largely superseded by 10BASE2 , which used a thinner and more flexible cable that was both cheaper and easier to use. More modern Ethernet variants use twisted pair and fiber optic links in conjunction with switches . Over

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1476-449: A loop-free logical topology using the SPB protocol or the older STP on the network switches. A node that is sending longer than the maximum transmission window for an Ethernet packet is considered to be jabbering . Depending on the physical topology, jabber detection and remedy differ somewhat. Great Recession The Great Recession was a period of market decline in economies around

1599-490: A minimum, there's a little 'froth' [in the U.S. housing market]...it's hard not to see that there are a lot of local bubbles". The Economist , writing at the same time, went further, saying, "[T]he worldwide rise in house prices is the biggest bubble in history". Real estate bubbles are (by definition of the word "bubble") followed by a price decrease (also known as a housing price crash ) that can result in many owners holding negative equity (a mortgage debt higher than

1722-572: A resolution preventing CFTC from regulating derivatives for another six months – when Born's term of office would expire. Ultimately, it was the collapse of a specific kind of derivative, the mortgage-backed security , that triggered the economic crisis of 2008. Paul Krugman wrote in 2009 that the run on the shadow banking system was the fundamental cause of the crisis. "As the shadow banking system expanded to rival or even surpass conventional banking in importance, politicians and government officials should have realised that they were re-creating

1845-665: A series of triggering events that began with the bursting of the United States housing bubble in 2005–2012. When housing prices fell and homeowners began to abandon their mortgages, the value of mortgage-backed securities held by investment banks declined in 2007–2008, causing several to collapse or be bailed out in September 2008. This 2007–2008 phase was called the subprime mortgage crisis . The combination of banks being unable to provide funds to businesses, and homeowners paying down debt rather than borrowing and spending, resulted in

1968-757: A sharp drop in international trade , rising unemployment and slumping commodity prices. Several economists predicted that recovery might not appear until 2011 and that the recession would be the worst since the Great Depression of the 1930s. Economist Paul Krugman once commented on this as seemingly the beginning of "a second Great Depression". Governments and central banks responded with fiscal policy and monetary policy initiatives to stimulate national economies and reduce financial system risks. The recession renewed interest in Keynesian economic ideas on how to combat recessionary conditions. Economists advise that

2091-509: A single network. This consolidation can: FCoE is encapsulated over Ethernet with the use of a dedicated Ethertype , 0x8906. A single 4-bit field (version) satisfies the IEEE sub-type requirements. The 802.1Q tag is optional but may be necessary in a given implementation. The SOF (start of frame) and EOF (end of frame) are encoded as specified in RFC   3643 . Reserved bits are present to guarantee that

2214-544: A standard for CSMA/CD based on the IEEE 802 draft. Because the DIX proposal was most technically complete and because of the speedy action taken by ECMA which decisively contributed to the conciliation of opinions within IEEE, the IEEE 802.3 CSMA/CD standard was approved in December 1982. IEEE published the 802.3 standard as a draft in 1983 and as a standard in 1985. Approval of Ethernet on

2337-425: A standard. As part of that process Xerox agreed to relinquish their 'Ethernet' trademark. The first standard was published on September 30, 1980, as "The Ethernet, A Local Area Network. Data Link Layer and Physical Layer Specifications". This so-called DIX standard (Digital Intel Xerox) specified 10 Mbit/s Ethernet, with 48-bit destination and source addresses and a global 16-bit Ethertype -type field. Version 2

2460-401: A switching loop. Autonegotiation is the procedure by which two connected devices choose common transmission parameters, e.g. speed and duplex mode. Autonegotiation was initially an optional feature, first introduced with 100BASE-TX (1995 IEEE 802.3u Fast Ethernet standard), and is backward compatible with 10BASE-T. The specification was improved in the 1998 release of IEEE 802.3. Autonegotiation

2583-510: A tool for taking excessive risks. Examples of vulnerabilities in the public sector included: statutory gaps and conflicts between regulators; ineffective use of regulatory authority; and ineffective crisis management capabilities. Bernanke also discussed " Too big to fail " institutions, monetary policy, and trade deficits. There are several "narratives" attempting to place the causes of the recession into context, with overlapping elements. Five such narratives include: Underlying narratives #1–3

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2706-413: Is a hypothesis that growing income inequality and wage stagnation encouraged families to increase their household debt to maintain their desired living standard, fueling the bubble. Further, this greater share of income flowing to the top increased the political power of business interests, who used that power to deregulate or limit regulation of the shadow banking system. Narrative #5 challenges

2829-530: Is commonly carried over Ethernet and so it is considered one of the key technologies that make up the Internet . Ethernet was developed at Xerox PARC between 1973 and 1974 as a means to allow Alto computers to communicate with each other. It was inspired by ALOHAnet , which Robert Metcalfe had studied as part of his PhD dissertation and was originally called the Alto Aloha Network. Metcalfe's idea

2952-407: Is either dropped or forwarded to another segment. This reduces the forwarding latency. One drawback of this method is that it does not readily allow a mixture of different link speeds. Another is that packets that have been corrupted are still propagated through the network. The eventual remedy for this was a return to the original store and forward approach of bridging, where the packet is read into

3075-433: Is in turn connected to the cable (with thin Ethernet the transceiver is usually integrated into the network adapter). While a simple passive wire is highly reliable for small networks, it is not reliable for large extended networks, where damage to the wire in a single place, or a single bad connector, can make the whole Ethernet segment unusable. Through the first half of the 1980s, Ethernet's 10BASE5 implementation used

3198-476: Is intended for just one destination. The network interface card interrupts the CPU only when applicable packets are received: the card ignores information not addressed to it. Use of a single cable also means that the data bandwidth is shared, such that, for example, available data bandwidth to each device is halved when two stations are simultaneously active. A collision happens when two stations attempt to transmit at

3321-409: Is mandatory for 1000BASE-T and faster. A switching loop or bridge loop occurs in computer networks when there is more than one Layer 2 ( OSI model ) path between two endpoints (e.g. multiple connections between two network switches or two ports on the same switch connected to each other). The loop creates broadcast storms as broadcasts and multicasts are forwarded by switches out every port ,

3444-616: Is now used to interconnect appliances and other personal devices . As Industrial Ethernet it is used in industrial applications and is quickly replacing legacy data transmission systems in the world's telecommunications networks. By 2010, the market for Ethernet equipment amounted to over $ 16 billion per year. In February 1980, the Institute of Electrical and Electronics Engineers (IEEE) started project 802 to standardize local area networks (LAN). The DIX group with Gary Robinson (DEC), Phil Arst (Intel), and Bob Printis (Xerox) submitted

3567-436: Is significantly better. In a modern Ethernet, the stations do not all share one channel through a shared cable or a simple repeater hub ; instead, each station communicates with a switch, which in turn forwards that traffic to the destination station. In this topology, collisions are only possible if station and switch attempt to communicate with each other at the same time, and collisions are limited to this link. Furthermore,

3690-463: Is the timing. Subprime lending increased from around 10% of mortgage origination historically to about 20% only from 2004 to 2006, with housing prices peaking in 2006. Blaming affordable housing regulations established in the 1990s for a sudden spike in subprime origination is problematic at best. A more proximate government action to the sudden rise in subprime lending was the SEC relaxing lending standards for

3813-412: Is used by the operating system on the receiving station to select the appropriate protocol module (e.g., an Internet Protocol version such as IPv4 ). Ethernet frames are said to be self-identifying , because of the EtherType field. Self-identifying frames make it possible to intermix multiple protocols on the same physical network and allow a single computer to use multiple protocols together. Despite

Fibre Channel over Ethernet - Misplaced Pages Continue

3936-518: The 10BASE-T standard introduced a full duplex mode of operation which became common with Fast Ethernet and the de facto standard with Gigabit Ethernet . In full duplex, switch and station can send and receive simultaneously, and therefore modern Ethernets are completely collision-free. For signal degradation and timing reasons, coaxial Ethernet segments have a restricted size. Somewhat larger networks can be built by using an Ethernet repeater . Early repeaters had only two ports, allowing, at most,

4059-503: The American Enterprise Institute , which advocates for private enterprise and limited government, have asserted that private lenders were encouraged to relax lending standards by government affordable housing policies. They cite The Housing and Community Development Act of 1992, which initially required that 30 percent or more of Fannie's and Freddie's loan purchases be related to affordable housing. The legislation gave HUD

4182-478: The Commodity Futures Trading Commission , put forth a policy paper asking for feedback from regulators, lobbyists, and legislators on the question of whether derivatives should be reported, sold through a central facility, or whether capital requirements should be required of their buyers. Greenspan, Rubin, and Levitt pressured her to withdraw the paper and Greenspan persuaded Congress to pass

4305-524: The IMF criteria for being a global recession only in the single calendar year 2009. That IMF definition requires a decline in annual real world GDP per‑capita . Despite the fact that quarterly data are being used as recession definition criteria by all G20 members , representing 85% of the world GDP , the International Monetary Fund (IMF) has decided – in the absence of

4428-545: The OSI model , Ethernet provides services up to and including the data link layer . The 48-bit MAC address was adopted by other IEEE 802 networking standards, including IEEE 802.11 ( Wi-Fi ), as well as by FDDI . EtherType values are also used in Subnetwork Access Protocol (SNAP) headers. Ethernet is widely used in homes and industry, and interworks well with wireless Wi-Fi technologies. The Internet Protocol

4551-573: The Spanning Tree Protocol (STP) to maintain a loop-free, meshed network, allowing physical loops for redundancy (STP) or load-balancing (SPB). Shortest Path Bridging includes the use of the link-state routing protocol IS-IS to allow larger networks with shortest path routes between devices. Advanced networking features also ensure port security, provide protection features such as MAC lockdown and broadcast radiation filtering, use VLANs to keep different classes of users separate while using

4674-429: The 19th and early 20th centuries, the current banking panic is a wholesale panic, not a retail panic. In the earlier episodes, depositors ran to their banks and demanded cash in exchange for their checking accounts. Unable to meet those demands, the banking system became insolvent. The current panic involved financial firms "running" on other financial firms by not renewing sale and repurchase agreements (repo) or increasing

4797-416: The 19th century. Yet, over the past 30-plus years, we permitted the growth of a shadow banking system – opaque and laden with short term debt – that rivaled the size of the traditional banking system. Key components of the market – for example, the multitrillion-dollar repo lending market, off-balance-sheet entities, and the use of over-the-counter derivatives – were hidden from view, without

4920-546: The CPU) the low level frame processing and SCSI protocol functions traditionally performed by Fibre Channel host bus adapters. The main application of FCoE is in data center storage area networks (SANs). FCoE has particular application in data centers due to the cabling reduction it makes possible, as well as in server virtualization applications, which often require many physical I/O connections per server. With FCoE, network (IP) and storage (SAN) data traffic can be consolidated using

5043-537: The FCIC Republican minority dissenting report also concluded that U.S. housing policies were not a robust explanation for a wider global housing bubble. The hypothesis that a primary cause of the crisis was U.S. government housing policy requiring banks to make risky loans has been widely disputed, with Paul Krugman referring to it as "imaginary history". One of the other challenges with blaming government regulations for essentially forcing banks to make risky loans

Fibre Channel over Ethernet - Misplaced Pages Continue

5166-433: The FCoE frame meets the minimum length requirement of Ethernet. Inside the encapsulated Fibre Channel frame, the frame header is retained so as to allow connecting to a storage network by passing on the Fibre Channel frame directly after de-encapsulation. The FIP (FCoE Initialization Protocol) is an integral part of FCoE. Its main goal is to discover and initialize FCoE capable entities connected to an Ethernet cloud. FIP uses

5289-521: The Federal Reserve has been widely discussed, the main point of controversy remains the lowering of the Federal funds rate to 1% for more than a year, which, according to Austrian theorists , injected huge amounts of "easy" credit-based money into the financial system and created an unsustainable economic boom. There is an argument that Greenspan's actions in the years 2002–2004 were actually motivated by

5412-416: The Federal Reserve. Further, American International Group (AIG) had insured mortgage-backed and other securities but was not required to maintain sufficient reserves to pay its obligations when debtors defaulted on these securities. AIG was contractually required to post additional collateral with many creditors and counter-parties, touching off controversy when over $ 100 billion of U.S. taxpayer money

5535-466: The Great Recession that began in the U.S. officially in December 2007 and lasted until June 2009, thus extending over 19 months. As with most other recessions, it appears that no known formal theoretical or empirical model was able to accurately predict the advance of this recession, except for minor signals in the sudden rise of forecast probabilities, which were still well under 50%. The recession

5658-484: The LAN was observed. This is in contrast with token passing LANs (Token Ring, Token Bus), all of which suffer throughput degradation as each new node comes into the LAN, due to token waits. This report was controversial, as modeling showed that collision-based networks theoretically became unstable under loads as low as 37% of nominal capacity. Many early researchers failed to understand these results. Performance on real networks

5781-738: The Summit on Financial Markets and the World Economy," dated November 15, 2008, leaders of the Group of 20 cited the following causes: During a period of strong global growth, growing capital flows, and prolonged stability earlier this decade, market participants sought higher yields without an adequate appreciation of the risks and failed to exercise proper due diligence. At the same time, weak underwriting standards, unsound risk management practices, increasingly complex and opaque financial products, and consequent excessive leverage combined to create vulnerabilities in

5904-544: The US, from $ 106,591 to $ 68,839 between 2005 and 2011. The US Financial Crisis Inquiry Commission , composed of six Democratic and four Republican appointees, reported its majority findings in January 2011. It concluded that "the crisis was avoidable and was caused by: There were two Republican dissenting FCIC reports. One of them, signed by three Republican appointees, concluded that there were multiple causes. In his separate dissent to

6027-478: The United States, and 21% in Denmark. Household defaults, underwater mortgages (where the loan balance exceeds the house value), foreclosures, and fire sales are now endemic to a number of economies. Household deleveraging by paying off debts or defaulting on them has begun in some countries. It has been most pronounced in the United States, where about two-thirds of the debt reduction reflects defaults." The onset of

6150-560: The academic definition, the recession ended in the United States in June or July 2009. Journalist Robert Kuttner has argued that 'The Great Recession' is a misnomer. According to Kuttner, "recessions are mild dips in the business cycle that are either self-correcting or soon cured by modest fiscal or monetary stimulus. Because of the continuing deflationary trap, it would be more accurate to call this decade's stagnant economy The Lesser Depression or The Great Deflation." The Great Recession met

6273-448: The advent of FCoE, SANs that would have traditionally used Fibre Channel is consolidated with Ethernet and becomes another network protocol running on the Ethernet fabric, alongside traditional traffic such as IP . FCoE operates on top of the data link layer in the OSI model which contrasts with most other well-known protocols that may use Ethernet, such as (for a storage-related example) iSCSI , which runs on top of TCP over IP . As

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6396-460: The bailout measures started under the Bush administration and continued during his administration as completed and mostly profitable as of December 2014 . As of January 2018 , bailout funds had been fully recovered by the government, when interest on loans is taken into consideration. A total of $ 626B was invested, loaned, or granted due to various bailout measures, while $ 390B had been returned to

6519-517: The bailouts. In 2008, TARP allocated $ 426.4 billion to various major financial institutions. However, the US collected $ 441.7 billion in return from these loans in 2010, recording a profit of $ 15.3 billion. Nonetheless, there was a political shift from the Democratic party. Examples include the rise of the Tea Party and the loss of Democratic majorities in subsequent elections. President Obama declared

6642-457: The capabilities of Fibre Channel over Ethernet networks: Computers can connect to FCoE with converged network adapters (CNAs), which contain both Fibre Channel host bus adapter (HBA) and Ethernet network interface controller (NIC) functionality on the same physical card. CNAs have one or more physical Ethernet ports. FCoE encapsulation can be done in software with a conventional Ethernet network interface card, however FCoE CNAs offload (from

6765-621: The course of its history, Ethernet data transfer rates have been increased from the original 2.94  Mbit/s to the latest 400 Gbit/s , with rates up to 1.6  Tbit/s under development. The Ethernet standards include several wiring and signaling variants of the OSI physical layer . Systems communicating over Ethernet divide a stream of data into shorter pieces called frames . Each frame contains source and destination addresses, and error-checking data so that damaged frames can be detected and discarded; most often, higher-layer protocols trigger retransmission of lost frames. Per

6888-574: The crisis and exposed other risky loans and over-inflated asset prices. With loan losses mounting and the fall of Lehman Brothers on September 15, 2008, a major panic broke out on the inter-bank loan market. There was the equivalent of a bank run on the shadow banking system , resulting in many large and well established investment banks and commercial banks in the United States and Europe suffering huge losses and even facing bankruptcy, resulting in massive public financial assistance (government bailouts). The global recession that followed resulted in

7011-668: The crisis) and vulnerabilities (i.e., structural weaknesses in the financial system, regulation and supervision) that amplified the shocks. Examples of triggers included: losses on subprime mortgage securities that began in 2007 and a run on the shadow banking system that began in mid-2007, which adversely affected the functioning of money markets. Examples of vulnerabilities in the private sector included: financial institution dependence on unstable sources of short-term funding such as repurchase agreements or Repos; deficiencies in corporate risk management; excessive use of leverage (borrowing to invest); and inappropriate usage of derivatives as

7134-442: The current value of the property). Several sources have noted the failure of the US government to supervise or even require transparency of the financial instruments known as derivatives . Derivatives such as credit default swaps (CDSs) were unregulated or barely regulated. Michael Lewis noted CDSs enabled speculators to stack bets on the same mortgage securities. This is analogous to allowing many persons to buy insurance on

7257-564: The depository system yet was not subject to the same regulatory oversight, making it vulnerable to a bank run . US mortgage-backed securities , which had risks that were hard to assess, were marketed around the world, as they offered higher yields than U.S. government bonds. Many of these securities were backed by subprime mortgages, which collapsed in value when the U.S. housing bubble burst during 2006 and homeowners began to default on their mortgage payments in large numbers starting in 2007. The emergence of subprime loan losses in 2007 began

7380-455: The destination and the source of each data packet. Ethernet establishes link-level connections, which can be defined using both the destination and source addresses. On reception of a transmission, the receiver uses the destination address to determine whether the transmission is relevant to the station or should be ignored. A network interface normally does not accept packets addressed to other Ethernet stations. An EtherType field in each frame

7503-517: The downturn. In advanced economies, during the five years preceding 2007, the ratio of household debt to income rose by an average of 39 percentage points, to 138 percent. In Denmark, Iceland, Ireland, the Netherlands, and Norway, debt peaked at more than 200 percent of household income. A surge in household debt to historic highs also occurred in emerging economies such as Estonia, Hungary, Latvia, and Lithuania. The concurrent boom in both house prices and

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7626-608: The economic crisis took most people by surprise. A 2009 paper identifies twelve economists and commentators who, between 2000 and 2006, predicted a recession based on the collapse of the then-booming housing market in the United States: Dean Baker , Wynne Godley , Fred Harrison , Michael Hudson , Eric Janszen , Med Jones Steve Keen , Jakob Brøchner Madsen , Jens Kjaer Sørensen, Kurt Richebächer , Nouriel Roubini , Peter Schiff , and Robert Shiller . By 2007, real estate bubbles were still under way in many parts of

7749-405: The economic headwinds that slowed the recovery: On the political front, widespread anger at banking bailouts and stimulus measures (begun by President George W. Bush and continued or expanded by President Obama ) with few consequences for banking leadership, were a factor in driving the country politically rightward starting in 2010. The Troubled Asset Relief Program (TARP) was the largest of

7872-564: The elimination of the chaining limits inherent in non-switched Ethernet have made switched Ethernet the dominant network technology. Simple switched Ethernet networks, while a great improvement over repeater-based Ethernet, suffer from single points of failure, attacks that trick switches or hosts into sending data to a machine even if it is not intended for it, scalability and security issues with regard to switching loops , broadcast radiation , and multicast traffic. Advanced networking features in switches use Shortest Path Bridging (SPB) or

7995-482: The emerging office communication market, including Siemens' support for the international standardization of Ethernet (April 10, 1981). Ingrid Fromm, Siemens' representative to IEEE 802, quickly achieved broader support for Ethernet beyond IEEE by the establishment of a competing Task Group "Local Networks" within the European standards body ECMA TC24. In March 1982, ECMA TC24 with its corporate members reached an agreement on

8118-449: The evolution of Ethernet technology, all generations of Ethernet (excluding early experimental versions) use the same frame formats. Mixed-speed networks can be built using Ethernet switches and repeaters supporting the desired Ethernet variants. Due to the ubiquity of Ethernet, and the ever-decreasing cost of the hardware needed to support it, by 2004 most manufacturers built Ethernet interfaces directly into PC motherboards , eliminating

8241-612: The farthest nodes and creates practical limits on how many machines can communicate on an Ethernet network. Segments joined by repeaters have to all operate at the same speed, making phased-in upgrades impossible. To alleviate these problems, bridging was created to communicate at the data link layer while isolating the physical layer. With bridging, only well-formed Ethernet packets are forwarded from one Ethernet segment to another; collisions and packet errors are isolated. At initial startup, Ethernet bridges work somewhat like Ethernet repeaters, passing all traffic between segments. By observing

8364-423: The financial crisis was the result." In May 2008, NPR explained in their Peabody Award winning program " The Giant Pool of Money " that a vast inflow of savings from developing nations flowed into the mortgage market, driving the U.S. housing bubble. This pool of fixed income savings increased from around $ 35 trillion in 2000 to about $ 70 trillion by 2008. NPR explained this money came from various sources, "[b]ut

8487-450: The following recovery weaker. Robert Reich claims the amount of debt in the US economy can be traced to economic inequality , assuming that middle-class wages remained stagnant while wealth concentrated at the top, and households "pull equity from their homes and overload on debt to maintain living standards". The IMF reported in April 2012: "Household debt soared in the years leading up to

8610-504: The group was split into three subgroups, and standardization proceeded separately for each proposal. Delays in the standards process put at risk the market introduction of the Xerox Star workstation and 3Com's Ethernet LAN products. With such business implications in mind, David Liddle (General Manager, Xerox Office Systems) and Metcalfe (3Com) strongly supported a proposal of Fritz Röscheisen ( Siemens Private Networks) for an alliance in

8733-439: The installed base, and leverage building design, and, thus, twisted-pair Ethernet was the next logical development in the mid-1980s. Ethernet on unshielded twisted-pair cables (UTP) began with StarLAN at 1 Mbit/s in the mid-1980s. In 1987 SynOptics introduced the first twisted-pair Ethernet at 10 Mbit/s in a star-wired cabling topology with a central hub, later called LattisNet . These evolved into 10BASE-T, which

8856-510: The international level was achieved by a similar, cross- partisan action with Fromm as the liaison officer working to integrate with International Electrotechnical Commission (IEC) Technical Committee 83 and International Organization for Standardization (ISO) Technical Committee 97 Sub Committee 6. The ISO 8802-3 standard was published in 1989. Ethernet has evolved to include higher bandwidth, improved medium access control methods, and different physical media. The multidrop coaxial cable

8979-533: The kind of financial vulnerability that made the Great Depression possible – and they should have responded by extending regulations and the financial safety net to cover these new institutions. Influential figures should have proclaimed a simple rule: anything that does what a bank does, anything that has to be rescued in crises the way banks are, should be regulated like a bank." He referred to this lack of controls as "malign neglect". During 2008, three of

9102-568: The largest U.S. investment banks either went bankrupt ( Lehman Brothers ) or were sold at fire sale prices to other banks ( Bear Stearns and Merrill Lynch ). The investment banks were not subject to the more stringent regulations applied to depository banks. These failures exacerbated the instability in the global financial system. The remaining two investment banks, Morgan Stanley and Goldman Sachs , potentially facing failure, opted to become commercial banks, thereby subjecting themselves to more stringent regulation but receiving access to credit via

9225-540: The largest computer networks in the world at that time. An Ethernet adapter card for the IBM PC was released in 1982, and, by 1985, 3Com had sold 100,000. In the 1980s, IBM's own PC Network product competed with Ethernet for the PC, and through the 1980s, LAN hardware, in general, was not common on PCs. However, in the mid to late 1980s, PC networking did become popular in offices and schools for printer and fileserver sharing, and among

9348-399: The length of the payload. The middle section of the frame consists of payload data including any headers for other protocols (for example, Internet Protocol) carried in the frame. The frame ends with a 32-bit cyclic redundancy check , which is used to detect corruption of data in transit . Notably, Ethernet packets have no time-to-live field , leading to possible problems in the presence of

9471-581: The main headline is that all sorts of poor countries became kind of rich, making things like TVs and selling us oil. China, India, Abu Dhabi, Saudi Arabia made a lot of money and banked it." Describing the crisis in Europe, Paul Krugman wrote in February 2012 that: "What we're basically looking at, then, is a balance of payments problem, in which capital flooded south after the creation of the euro, leading to overvaluation in southern Europe." Another narrative about

9594-462: The majority and minority opinions of the FCIC, Commissioner Peter J. Wallison of the American Enterprise Institute (AEI) primarily blamed U.S. housing policy, including the actions of Fannie and Freddie , for the crisis. He wrote: "When the bubble began to deflate in mid-2007, the low quality and high risk loans engendered by government policies failed in unprecedented numbers." In its "Declaration of

9717-631: The many diverse competing LAN technologies of that decade, Ethernet was one of the most popular. Parallel port based Ethernet adapters were produced for a time, with drivers for DOS and Windows. By the early 1990s, Ethernet became so prevalent that Ethernet ports began to appear on some PCs and most workstations . This process was greatly sped up with the introduction of 10BASE-T and its relatively small modular connector , at which point Ethernet ports appeared even on low-end motherboards. Since then, Ethernet technology has evolved to meet new bandwidth and market requirements. In addition to computers, Ethernet

9840-401: The mixing of speeds, both of which are critical to the incremental deployment of faster Ethernet variants. In 1989, Motorola Codex introduced their 6310 EtherSpan, and Kalpana introduced their EtherSwitch; these were examples of the first commercial Ethernet switches. Early switches such as this used cut-through switching where only the header of the incoming packet is examined before it

9963-470: The need for a separate network card. Ethernet was originally based on the idea of computers communicating over a shared coaxial cable acting as a broadcast transmission medium. The method used was similar to those used in radio systems, with the common cable providing the communication channel likened to the Luminiferous aether in 19th-century physics, and it was from this reference that the name Ethernet

10086-662: The need to take the U.S. economy out of the early 2000s recession caused by the bursting of the dot-com bubble : although by doing so he did not avert the crisis, but only postponed it. Another narrative focuses on high levels of private debt in the US economy. USA household debt as a percentage of annual disposable personal income was 127% at the end of 2007, versus 77% in 1990. Faced with increasing mortgage payments as their adjustable rate mortgage payments increased, households began to default in record numbers, rendering mortgage-backed securities worthless. High private debt levels also impact growth by making recessions deeper and

10209-470: The network. Despite the physical star topology and the presence of separate transmit and receive channels in the twisted pair and fiber media, repeater-based Ethernet networks still use half-duplex and CSMA/CD, with only minimal activity by the repeater, primarily generation of the jam signal in dealing with packet collisions. Every packet is sent to every other port on the repeater, so bandwidth and security problems are not addressed. The total throughput of

10332-625: The now-ubiquitous twisted pair with 10BASE-T. By the end of the 1980s, Ethernet was clearly the dominant network technology. In the process, 3Com became a major company. 3Com shipped its first 10 Mbit/s Ethernet 3C100 NIC in March 1981, and that year started selling adapters for PDP-11s and VAXes , as well as Multibus -based Intel and Sun Microsystems computers. This was followed quickly by DEC's Unibus to Ethernet adapter, which DEC sold and used internally to build its own corporate network, which reached over 10,000 nodes by 1986, making it one of

10455-535: The obligation and defaulted; U.S. taxpayers paid over $ 100 billion to global financial institutions to honor AIG obligations, generating considerable outrage. A 2008 investigative article in The Washington Post found leading government officials at the time (Federal Reserve Board Chairman Alan Greenspan , Treasury Secretary Robert Rubin , and SEC Chairman Arthur Levitt ) vehemently opposed any regulation of derivatives. In 1998, Brooksley E. Born , head of

10578-577: The option to include a native fibre channel module, allowing you to connect the S5000 directly to an FC SAN environment. Ethernet Ethernet ( / ˈ iː θ ər n ɛ t / EE -thər-net ) is a family of wired computer networking technologies commonly used in local area networks (LAN), metropolitan area networks (MAN) and wide area networks (WAN). It was commercially introduced in 1980 and first standardized in 1983 as IEEE 802.3 . Ethernet has since been refined to support higher bit rates ,

10701-484: The origin has been focused on the respective parts played by public monetary policy (notably in the US) and by the practices of private financial institutions. In the U.S., mortgage funding was unusually decentralised, opaque, and competitive, and it is believed that competition between lenders for revenue and market share contributed to declining underwriting standards and risky lending. While Alan Greenspan's role as Chairman of

10824-530: The planet. Though no one knew they were in it at the time, the Great Recession had a significant economic and political impact on the United States. While the recession technically lasted from December 2007 – June 2009 (the nominal GDP trough), many important economic variables did not regain pre-recession (November or Q4 2007) levels until 2011–2016. For example, real GDP fell $ 650 billion (4.3%) and did not recover its $ 15 trillion pre-recession level until Q3 2011. Household net worth, which reflects

10947-405: The popular claim (narrative #4) that subprime borrowers with shoddy credit caused the crisis by buying homes they couldn't afford. This narrative is supported by new research showing that the biggest growth of mortgage debt during the U.S. housing boom came from those with good credit scores in the middle and top of the credit score distribution – and that these borrowers accounted for

11070-450: The port they are intended for, traffic on a switched Ethernet is less public than on shared-medium Ethernet. Despite this, switched Ethernet should still be regarded as an insecure network technology, because it is easy to subvert switched Ethernet systems by means such as ARP spoofing and MAC flooding . The bandwidth advantages, the improved isolation of devices from each other, the ability to easily mix different speeds of devices and

11193-512: The power to set future requirements. These rose to 42 percent in 1995 and 50 percent in 2000, and by 2008 a 56 percent minimum was established. However, the Financial Crisis Inquiry Commission (FCIC) Democratic majority report concluded that Fannie & Freddie "were not a primary cause" of the crisis and that CRA was not a factor in the crisis. Further, since housing bubbles appeared in multiple countries in Europe as well,

11316-410: The protections we had constructed to prevent financial meltdowns. We had a 21st-century financial system with 19th-century safeguards. The Gramm–Leach–Bliley Act (1999), which reduced the regulation of banks by allowing commercial and investment banks to merge, has also been blamed for the crisis, by Nobel Prize –winning economist Joseph Stiglitz among others. Peter Wallison and Edward Pinto of

11439-402: The recession have been described as a symptom of another, deeper crisis by a number of economists. For example, Ravi Batra argues that growing inequality of financial capitalism produces speculative bubbles that burst and result in depression and major political changes . Feminist economists Ailsa McKay and Margunn Bjørnholt argue that the financial crisis and the response to it revealed

11562-521: The recession took place at the global level. According to the U.S. National Bureau of Economic Research (the official arbiter of U.S. recessions) the recession began in December 2007 and ended in June 2009, and thus extended over eighteen months. The years leading up to the crisis were characterized by an exorbitant rise in asset prices and associated boom in economic demand. Further, the U.S. shadow banking system (i.e., non-depository financial institutions such as investment banks) had grown to rival

11685-488: The recovery was that both individuals and businesses paid down debts for several years, as opposed to borrowing and spending or investing as had historically been the case. This shift to a private sector surplus drove a sizable government deficit. However, the federal government held spending at about $ 3.5 trillion from fiscal years 2009–2014 (thereby decreasing it as a percent of GDP), a form of austerity . Then-Fed Chair Ben Bernanke explained during November 2012 several of

11808-411: The repeater is limited to that of a single link, and all links must operate at the same speed. While repeaters can isolate some aspects of Ethernet segments , such as cable breakages, they still forward all traffic to all Ethernet devices. The entire network is one collision domain , and all hosts have to be able to detect collisions anywhere on the network. This limits the number of repeaters between

11931-461: The repo margin ("haircut"), forcing massive deleveraging, and resulting in the banking system being insolvent. The Financial Crisis Inquiry Commission reported in January 2011: In the early part of the 20th century, we erected a series of protections – the Federal Reserve as a lender of last resort , federal deposit insurance, ample regulations – to provide a bulwark against the panics that had regularly plagued America's banking system in

12054-496: The same house. Speculators that bought CDS protection were betting significant mortgage security defaults would occur, while the sellers (such as AIG ) bet they would not. An unlimited amount could be wagered on the same housing-related securities, provided buyers and sellers of the CDS could be found. When massive defaults occurred on underlying mortgage securities, companies like AIG that were selling CDS were unable to perform their side of

12177-549: The same physical infrastructure, employ multilayer switching to route between different classes, and use link aggregation to add bandwidth to overloaded links and to provide some redundancy. In 2016, Ethernet replaced InfiniBand as the most popular system interconnect of TOP500 supercomputers. The Ethernet physical layer evolved over a considerable time span and encompasses coaxial, twisted pair and fiber-optic physical media interfaces, with speeds from 1 Mbit/s to 400 Gbit/s . The first introduction of twisted-pair CSMA/CD

12300-482: The same time, and there is no collision domain. This doubles the aggregate bandwidth of the link and is sometimes advertised as double the link speed (for example, 200 Mbit/s for Fast Ethernet). The elimination of the collision domain for these connections also means that all the link's bandwidth can be used by the two devices on that segment and that segment length is not limited by the constraints of collision detection. Since packets are typically delivered only to

12423-512: The same time. They corrupt transmitted data and require stations to re-transmit. The lost data and re-transmission reduces throughput. In the worst case, where multiple active hosts connected with maximum allowed cable length attempt to transmit many short frames, excessive collisions can reduce throughput dramatically. However, a Xerox report in 1980 studied performance of an existing Ethernet installation under both normal and artificially generated heavy load. The report claimed that 98% throughput on

12546-413: The so-called Blue Book CSMA/CD specification as a candidate for the LAN specification. In addition to CSMA/CD, Token Ring (supported by IBM) and Token Bus (selected and henceforward supported by General Motors ) were also considered as candidates for a LAN standard. Competing proposals and broad interest in the initiative led to strong disagreement over which technology to standardize. In December 1980,

12669-411: The source addresses of incoming frames, the bridge then builds an address table associating addresses to segments. Once an address is learned, the bridge forwards network traffic destined for that address only to the associated segment, improving overall performance. Broadcast traffic is still forwarded to all network segments. Bridges also overcome the limits on total segments between two hosts and allow

12792-518: The stimulus measures such as quantitative easing (pumping money into the system) and holding down central bank wholesale lending interest rate should be withdrawn as soon as economies recover enough to "chart a path to sustainable growth ". The distribution of household incomes in the United States became more unequal during the post-2008 economic recovery . Income inequality in the United States grew from 2005 to 2012 in more than two thirds of metropolitan areas. Median household wealth fell 35% in

12915-649: The stock market meant that household debt relative to assets held broadly stable, which masked households' growing exposure to a sharp fall in asset prices. When house prices declined, ushering in the global financial crisis, many households saw their wealth shrink relative to their debt, and, with less income and more unemployment, found it harder to meet mortgage payments. By the end of 2011, real house prices had fallen from their peak by about 41% in Ireland, 29% in Iceland, 23% in Spain and

13038-478: The switch or switches will repeatedly rebroadcast the broadcast messages flooding the network. Since the Layer 2 header does not support a time to live (TTL) value, if a frame is sent into a looped topology, it can loop forever. A physical topology that contains switching or bridge loops is attractive for redundancy reasons, yet a switched network must not have loops. The solution is to allow physical loops, but create

13161-482: The system was deployed at PARC, Metcalfe and Boggs published a seminal paper. Ron Crane , Yogen Dalal , Robert Garner, Hal Murray, Roy Ogus, Dave Redell and John Shoch facilitated the upgrade from the original 2.94 Mbit/s protocol to the 10 Mbit/s protocol, which was released to the market in 1980. Metcalfe left Xerox in June 1979 to form 3Com . He convinced Digital Equipment Corporation (DEC), Intel , and Xerox to work together to promote Ethernet as

13284-490: The system. Policy-makers, regulators and supervisors, in some advanced countries, did not adequately appreciate and address the risks building up in financial markets, keep pace with financial innovation, or take into account the systemic ramifications of domestic regulatory actions. Federal Reserve Chair Ben Bernanke testified in September 2010 before the FCIC regarding the causes of the crisis. He wrote that there were shocks or triggers (i.e., particular events that touched off

13407-564: The time). In April 2008, an early implementor was Nuova Systems, a subsidiary of Cisco Systems , which announced a switch. Brocade Communications Systems also announced support in 2008. After the Great Recession , any new technology had a hard time getting established. In June 2009, the FCoE technology that had been defined as part of the International Committee for Information Technology Standards (INCITS) T11 FC-BB-5 standard

13530-492: The top investment banks during an April 2004 meeting with bank leaders. These banks increased their risk-taking shortly thereafter, significantly increasing their purchases and securitization of lower-quality mortgages, thus encouraging additional subprime and Alt-A lending by mortgage companies. This action by its investment bank competitors also resulted in Fannie Mae and Freddie Mac taking on more risk. The financial crisis and

13653-515: The value of both stock markets and housing prices, fell $ 11.5 trillion (17.3%) and did not regain its pre-recession level of $ 66.4 trillion until Q3 2012. The number of persons with jobs (total non-farm payrolls) fell 8.6 million (6.2%) and did not regain the pre-recession level of 138.3 million until May 2014. The unemployment rate peaked at 10.0% in October 2009 and did not return to its pre-recession level of 4.7% until May 2016. A key dynamic slowing

13776-453: The word "recession" exist: one sense referring definitively to "a period of reduced economic activity" and ongoing hardship; and the more allegoric interpretation used in economics , which is defined operationally , referring specifically to the contraction phase of a business cycle , with two or more consecutive quarters of GDP contraction (negative GDP growth rate) and typically used to influence abrupt changes in monetary policy. Under

13899-486: The world that occurred from late 2007 to mid-2009. The scale and timing of the recession varied from country to country (see map). At the time, the International Monetary Fund (IMF) concluded that it was the most severe economic and financial meltdown since the Great Depression . The causes of the Great Recession include a combination of vulnerabilities that developed in the financial system, along with

14022-660: The world, especially in the United States , France, the United Kingdom , Spain , the Netherlands, Australia, the United Arab Emirates, New Zealand , Ireland , Poland , South Africa , Greece , Bulgaria , Croatia , Norway , Singapore , South Korea , Sweden , Finland , Argentina , the Baltic states , India , Romania , Ukraine and China . U.S. Federal Reserve Chairman Alan Greenspan said in mid-2005 that "at

14145-766: Was StarLAN , standardized as 802.3 1BASE5. While 1BASE5 had little market penetration, it defined the physical apparatus (wire, plug/jack, pin-out, and wiring plan) that would be carried over to 10BASE-T through 10GBASE-T. The most common forms used are 10BASE-T, 100BASE-TX, and 1000BASE-T . All three use twisted-pair cables and 8P8C modular connectors . They run at 10 Mbit/s , 100 Mbit/s , and 1 Gbit/s , respectively. Fiber optic variants of Ethernet (that commonly use SFP modules ) are also very popular in larger networks, offering high performance, better electrical isolation and longer distance (tens of kilometers with some versions). In general, network protocol stack software will work similarly on all varieties. In IEEE 802.3,

14268-435: Was derived. Original Ethernet's shared coaxial cable (the shared medium) traversed a building or campus to every attached machine. A scheme known as carrier-sense multiple access with collision detection (CSMA/CD) governed the way the computers shared the channel. This scheme was simpler than competing Token Ring or Token Bus technologies. Computers are connected to an Attachment Unit Interface (AUI) transceiver , which

14391-446: Was designed for point-to-point links only, and all termination was built into the device. This changed repeaters from a specialist device used at the center of large networks to a device that every twisted pair-based network with more than two machines had to use. The tree structure that resulted from this made Ethernet networks easier to maintain by preventing most faults with one peer or its associated cable from affecting other devices on

14514-549: Was essentially to limit the Aloha-like signals inside a cable, instead of broadcasting into the air. The idea was first documented in a memo that Metcalfe wrote on May 22, 1973, where he named it after the luminiferous aether once postulated to exist as an "omnipresent, completely passive medium for the propagation of electromagnetic waves." In 1975, Xerox filed a patent application listing Metcalfe, David Boggs , Chuck Thacker , and Butler Lampson as inventors. In 1976, after

14637-561: Was forwarded to ANSI for publication. In May 2010, the FC-BB-5 standard was published as ANSI/INCITS 462-2010. Some additional work was done in the INCITS. Data center switches from Force10 and Dell PowerConnect supported FCoE and in June 2013, Dell Networking , which is the new brand -name for all networking portfolio of Dell, introduced the S5000 series which can be a fully native FCoE switch with

14760-535: Was not felt equally around the world; whereas most of the world's developed economies , particularly in North America, South America and Europe, fell into a severe, sustained recession, many more recently developing economies suffered far less impact, particularly China , India and Indonesia , whose economies grew substantially during this period. Similarly, Oceania suffered minimal impact , in part due to its proximity to Asian markets. Two interpretations of

14883-453: Was paid out to major global financial institutions on behalf of AIG. While this money was legally owed to the banks by AIG (under agreements made via credit default swaps purchased from AIG by the institutions), a number of Congressmen and media members expressed outrage that taxpayer money was used to bail out banks. Economist Gary Gorton wrote in May 2009 Unlike the historical banking panics of

15006-463: Was published in November 1982 and defines what has become known as Ethernet II . Formal standardization efforts proceeded at the same time and resulted in the publication of IEEE 802.3 on June 23, 1983. Ethernet initially competed with Token Ring and other proprietary protocols . Ethernet was able to adapt to market needs, and with 10BASE2 shift to inexpensive thin coaxial cable, and from 1990 to

15129-407: Was replaced with physical point-to-point links connected by Ethernet repeaters or switches . Ethernet stations communicate by sending each other data packets : blocks of data individually sent and delivered. As with other IEEE 802 LANs, adapters come programmed with globally unique 48-bit MAC address so that each Ethernet station has a unique address. The MAC addresses are used to specify both

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