70-561: The Juniper MX Series is a family of ethernet routers and switches designed and manufactured by Juniper Networks . In 2006, Juniper released the first of the MX-series, the MX960, MX240, and MX480. The second generation routers, called MX "3D", were first released in 2009 and featured a new Trio chipset and IPv6 support. In 2013, the MX routers were improved to increase their bandwidth, and
140-459: 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
210-555: A WAN. Many WANs are, however, built for one particular organization and are private. WANs can be separated from local area networks (LANs) in that the latter refers to physically proximal networks. The textbook definition of a WAN is a computer network spanning regions, countries, or even the world. However, in terms of the application of communication protocols and concepts, it may be best to view WANs as computer networking technologies used to transmit data over long distances, and between different networks. This distinction stems from
280-515: 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
350-515: 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
420-581: 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
490-456: A large geographic area. Wide area networks are often established with leased telecommunication circuits . Businesses, as well as schools and government entities, use wide area networks to relay data to staff, students, clients, buyers and suppliers from various locations around the world. In essence, this mode of telecommunication allows a business to effectively carry out its daily function regardless of location. The Internet may be considered
560-460: 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. Wide area network A wide area network ( WAN ) is a telecommunications network that extends over
630-534: A new line of MX "3D" products were introduced, using Juniper's programmable Trio chipset. Trio is a proprietary semiconductor technology with custom network instructions. It provides a cross between network processing units and ASICs . IPv6 features were added and the MX80, a smaller 80 Gbit/s router, was introduced the following year. In 2011 new switch fabric cards increased the capacity of MX 3D routers. In May 2011 Juniper introduced several new products including
700-524: A policy manager for subscriber management systems." In October 2012, Juniper introduced the MX2020 and 2010 3D Universal Edge Routers, with throughputs of 80 Tbit/s and 40 Tbit/s respectively. Juniper also released a video caching system for the MX family and a suite of software applications that include parental control, firewall and traffic monitoring. New "Virtual Chassis" features allowed network operators to manage multiple boxes as though they were
770-534: A single router or switch. In 2013, Juniper introduced new line cards for the MX series and a new switch fabric module, intended to upgrade the MX series' for higher bandwidth needs and for software-defined networking applications. The capacity of the MX240, 480 and 960 were increased by double or more. A new Multiservice Modular Interface Card (MS-MIC) was incorporated that supports up to 9 Gbit/s for services like tunneling software. In March 2013, Juniper released
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#1732790557697840-556: 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
910-425: 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
980-401: 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
1050-402: 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 the course of its history, Ethernet data transfer rates have been increased from the original 2.94 Mbit/s to
1120-535: A virtualized MX 3D router, the vMX 3D, was released in 2014. Utilizing the Juniper Extension Toolkit (JET), third party software can be integrated into the routers. On October 18, 2006, the MX Series was publicly announced. Before its release, Ethernet aggregation was a missing component of Juniper's edge network products, which was causing it to lose market-share to Alcatel . The MX Series
1190-543: 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
1260-407: 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
1330-433: 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
1400-479: 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
1470-409: 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 ,
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#17327905576971540-621: 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
1610-436: 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,
1680-412: 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
1750-518: 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,
1820-559: 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
1890-583: 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
1960-646: The EX9200 switch, which isn't part of the MX Series, but uses the same software and Trio chipset. A virtualized MX series 3D router, the vMX 3D, was introduced in November 2014. A suite of updates were announced in late 2015. New MPC line cards were introduced, which have a throughput of up to 1.6 Tbit/s. Simultaneously the Juniper Extension Toolkit (JET) was announced. JET is a programming interface for integrating third-party applications that automate provisioning, maintenance and other tasks. The Junos Telemetry Interface
2030-721: The Internet. WANs are often built using leased lines . At each end of the leased line, a router connects the LAN on one side with a second router within the LAN on the other. Because leased lines can be very expensive, instead of using leased lines, WANs can also be built using less costly circuit switching or packet switching methods. Network protocols including TCP/IP deliver transport and addressing functions. Protocols including Packet over SONET/SDH , Multiprotocol Label Switching (MPLS), Asynchronous Transfer Mode (ATM) and Frame Relay are often used by service providers to deliver
2100-438: 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
2170-545: The MX5, MX10 and MX40 3D routers, which have a throughput of 20, 40 and 60 Gbit/s respectively and can each be upgraded to an MX80. A collection of features called MobileNext was introduced in 2011 at Mobile World Congress , then discontinued in August 2013. According to Network World , it allowed MX 3D products to serve as a mobile "gateway, an authentication and management control plan for 2G/3G and LTE mobile packet cores and as
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2240-455: 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
2310-564: 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
2380-487: 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
2450-449: 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
2520-636: The fact that common local area network (LAN) technologies operating at lower layers of the OSI model (such as the forms of Ethernet or Wi-Fi ) are often designed for physically proximal networks, and thus cannot transmit data over tens, hundreds, or even thousands of miles or kilometres. WANs are used to connect LANs and other types of networks together so that users and computers in one location can communicate with users and computers in other locations. Many WANs are built for one particular organization and are private. Others, built by Internet service providers , provide connections from an organization's LAN to
2590-612: 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
2660-510: 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
2730-439: 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
2800-510: 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
2870-547: 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
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2940-502: 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
3010-399: 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
3080-647: The links that are used in WANs. It is also possible to build a WAN with Ethernet . Academic research into wide area networks can be broken down into three areas: mathematical models , network emulation , and network simulation . Performance improvements are sometimes delivered via wide area file services or WAN optimization . Of the approximately four billion addresses defined in IPv4, about 18 million addresses in three ranges are reserved for use in private networks . Packets addressed in these ranges are not routable on
3150-631: 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
3220-401: 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
3290-476: 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
3360-470: 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
3430-629: 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
3500-450: 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
3570-419: The private addresses, for transmission across the public network. Additionally, encapsulated packets may be encrypted to secure their data. Many technologies are available for wide area network links. Examples include circuit-switched telephone lines, radio wave transmission, and optical fiber . New developments have successively increased transmission rates. In c. 1960 , a 110 bit/s line
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#17327905576973640-509: The public Internet; they are ignored by all public routers. Therefore, private hosts cannot directly communicate with public networks, but require network address translation at a routing gateway for this purpose. Since two private networks, e.g., two branch offices, cannot directly communicate via the public Internet, the two networks must be bridged across the Internet via a virtual private network (VPN) or other form of IP tunnel that encapsulates packets, including their headers containing
3710-411: 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
3780-549: 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
3850-482: 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
3920-512: 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
3990-413: 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,
4060-411: 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
4130-482: 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
4200-533: 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
4270-766: 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,
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#17327905576974340-531: Was also announced at the same time. It reports data to applications and other equipment to automate changes to the network in response to faults or in order optimize performance. According to Juniper's website, Juniper's current MX Series products include the following: 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
4410-399: Was commercially introduced in 1980 and first standardized in 1983 as IEEE 802.3 . Ethernet has since been refined to support higher bit rates , 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
4480-435: 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
4550-446: 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
4620-555: 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
4690-459: Was late to market, but it was well received by analysts and customers. It was part of a trend at-the-time to incorporate additional software features in routers and switches. The first product release of the MX series was the MX960, a 14-slot, 480 Gbit/s switch and router. In late 2006, Juniper introduced the MX240 and MX480, which are smaller versions of the 960. They had a throughput of 240 Gbit/s and 480 Gbit/s respectively. In 2009
4760-941: Was normal on the edge of the WAN, while core links of 56 or 64 kbit/s were considered fast. Today, households are connected to the Internet with dial-up , asymmetric digital subscriber line (ADSL), cable , WiMAX , cellular network or fiber . The speeds that people can currently use range from 28.8 kbit/s through a 28K modem over a telephone connection to speeds as high as 100 Gbit/s using 100 Gigabit Ethernet . The following communication and networking technologies have been used to implement WANs. AT&T conducted trials in 2017 for business use of 400-gigabit Ethernet . Researchers Robert Maher, Alex Alvarado, Domaniç Lavery, and Polina Bayvel of University College London were able to increase networking speeds to 1.125 terabits per second. Christos Santis, graduate student Scott Steger, Amnon Yariv, Martin and Eileen Summerfield developed
4830-412: 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
4900-407: 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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