Please use the following glossary of related industry terms as a reference.
| 1000Base-T | 1000BASE-T , also known as IEEE 802.3ab, is a standard released in 1999 to provide 1 gigabit/second connections over unshielded twisted pair copper cables. 1000Base-T requires utilization of all four pairs of the twisted-pair cable. |
| 10GBase-T | 10GBASE-T, or IEEE 802.3an-2006, is a standard released in 2006 to provide 10 gigabit/second connections over unshielded or shielded twisted pair cables, over distances up to 100 metres (330 ft). |
| 10GbE | Abbreviated form for 10 Gigabit Ethernet |
| 64B/66B | In data networking and transmission, 64B/66B is a line code that transforms 64-bit data to 66-bit line code to achieve DC-balance and bounded disparity, and yet provide enough state changes to allow reasonable clock recovery. This means that there are just as many 1s as 0s in a string of two symbols, and that there are not too many 1s or 0s in a row. This is an important attribute in a signal that needs to be sent at high rates because it helps reduce intersymbol interference. |
| 8b/10b | In telecommunications, 8b/10b is a line code that maps 8-bit symbols to 10-bit symbols to achieve DC-balance and bounded disparity, and yet provide enough state changes to allow reasonable clock recovery. This means that the difference between the count of 1s and 0s in a string of at least 20 bits is no more than 2, and that there are not more than five 1s or 0s in a row. |
| Alien Crosstalk | Alien crosstalk (AXT) is electromagnetic noise that can occur in a cable that runs alongside one or more other signal-carrying cables. The term "alien" arises from the fact that this form of crosstalk occurs between different cables in a group or bundle, rather than between individual wires or circuits within a single cable. |
| Bandwidth | Bandwidth refers to the data rate supported by a network connection or interface. Most commonly bandwidth is expressed in terms of bits per second (bps); with a "k" (for kilo) or "G" (for Giga) preceding. |
| BER | The bit error rate (BER) is the percentage of bits that have errors relative to the total number of bits received in a transmission, usually expressed as ten to a negative power. BER is one of the prime considerations in determining signal quality |
| Category 5e | Category 5e (or Cat 5e) cable is an enhanced version of Category 5 cable that adds specifications for far end crosstalk (FEXT). It was formally defined in 2001 as the TIA/EIA-568-B standard, which no longer recognizes the original Cat 5 specification. Upon formal definition, Cat 5e became the primary cable of choice for transmitting 1000Base-T. |
| Category 6 | Category 6 (Cat6) copper twisted pair cable is a cable standard that is backward compatible with the Category 5/5e and Category 3 cable standards. Cat-6, with performance of up to 250 MHz, provides more stringent specifications for crosstalk and system noise. |
| Category 6A | Enhancing Category 6 twisted pair copper cables further, Category 6A (Augmented Category 6 or Cat 6A cable) was defined in February 2008 in ANSI/TIA/EIA-568-B.2-10. Category 6A operates at frequencies up to 500 MHz. Cat6A cables enable full reach 100 meter performance of 10GBase-T. |
| Category 7 | Category 7 cable (Cat7), defined by ISO/IEC 11801:2002 category 7/class F, is a twisted-pair copper cable which can be made to be backwards compatible with traditional Cat5 and Cat6 Ethernet cable. Cat7 cable, rated for transmission frequencies up to 600 Mhz, features even more stringent specifications for crosstalk and system noise than Cat6; to achieve this, shielding has been added for individual wire pairs and the cable as a whole. Cat 7 cables enable full reach 100 meter performance of 10GBase-T. |
| Class D | Class D cables refer to Category 6 and Category 6A cables (see Glossary) |
| Class E | Class E cables refer to Category 5 cables. Category 5e (or Cat 5e) cable is an enhanced version of Category 5 cable that adds specifications for far end crosstalk (FEXT). It was formally defined in 2001 as the TIA/EIA-568-B standard, which no longer recognizes the original Cat 5 specification. Upon formal definition, Cat 5e became the primary cable of choice for transmitting 1000Base-T. |
| Class F | Class F cables refer to Category 7 cables. Category 7 cable (Cat7), defined by ISO/IEC 11801:2002 category 7/class F, is a twisted-pair copper cable which can be made to be backwards compatible with traditional Cat5 and Cat6 Ethernet cable. Cat7 cable, rated for transmission frequencies up to 600 Mhz, features even more stringent specifications for crosstalk and system noise than Cat6; to achieve this, shielding has been added for individual wire pairs and the cable as a whole. Cat 7 cables enable full reach 100 meter performance of 10GBase-T. |
| Crosstalk | Crosstalk (XT) refers to when a signal transmitted on one channel of a transmission system creates an undesired effect in another channel. Crosstalk is usually caused by undesired capacitive, inductive, or conductive coupling from channel to another. |
| Duplex | Duplex refers to the ability to send and receive data over the same channel. |
| Ethernet Alliance | The Ethernet Alliance is a consortium of component suppliers, industry experts, university and government professionals. The primary objective is to promote industry interoperability, certification, education and awareness of Ethernet technology and products based on existing and emerging IEEE 802 Ethernet standards: http://www.ethernetalliance.org/ The Ethernet Alliance initiatives include, but are not limited to 10GBASE-T, backplane Ethernet; Energy Efficient Ethernet (EEE); Higher Speed Ethernet (HSE), encompassing 40 Gb/s and 100 Gb/s; Carrier Ethernet, Data Center Bridging (DCB) and Fibre Channel over Ethernet (FCoE); Power over Ethernet (PoE) and Power over Ethernet Plus (PoE+); SFP+ and EDC; test and measurement and much more. |
| FEXT | Far End Crosstalk (FEXT) is interference between two pairs in one cable; as measured at the end of the cable furthest from the transmitter. |
| FSA | In 1994, the Fabless Semiconductor Association (FSA) was established to promote the fabless business model globally. A fabless company concentrates its research and development resources on the end market without investing capital resources to stay current in semiconductor process technology. In other words, they are fab-less, and do not own a fab or fabrication facility - instead they rely on pure-play semiconductor foundries to manufacture their semiconductor chips on their behalf. In December 2007, the FSA transitioned to the GSA - the Global Semiconductor Alliance. |
| Full Duplex | Full Duplex allows communication in both directions simultaneously over the same channel. |
| Half-duplex channel | A channel of a duplex system arranged to permit operation in either one direction but not in both directions simultaneously. |
| IEEE | The IEEE (Institute of Electrical and Electronics Engineers) describes itself as "the world's largest technical professional society -- promoting the development and application of electrotechnology and allied sciences for the benefit of humanity, the advancement of the profession, and the well-being of our members." Pronounced "eye-triple-e", the organization develops basic, formal standard for various technologies, each designated via a standardized numbering system. |
| IEEE 802.3 | The IEEE 802.3 Working Group develops standards for Ethernet based LANs. The list of completed standards includes: IEEE Std 802.3z-1998, Gigabit Ethernet. IEEE Std 802.3aa-1998, Maintenance #5. IEEE Std 802.3ab-1999, 1000BASE-T. IEEE Std 802.3ac-1998, VLAN TAG. IEEE Std 802.3ad-2000, Link Aggregation. IEEE Std 802.3ae-2002, 10Gb/s Ethernet. IEEE Std 802.3af-2003, DTE Power via MDI. IEEE Std 802.3ag-2002, Maintenance #6 (Revision). IEEE Std 802.3ah-2004, Ethernet in the First Mile. IEEE Std 802.3aj-2003, Maintenance #7. IEEE Std 802.3ak-2004, 10GBASE-CX4. IEEE Std 802.3REVam-2005, Maintenance #8 (Revision). IEEE Std 802.3an-2006, 10GBASE-T. IEEE Std 802.3ap-2007, Backplane Ethernet. IEEE Std 802.3aq-2006, 10GBASE-LRM. IEEE P802.3ar, Congestion Management. IEEE Std 802.3as-2006, Frame Expansion. IEEE Std 802.3-2005/Cor 1-2006 (IEEE 802.3au) DTE Power Isolation Corrigendum. IEEE Std 802.3-2005/Cor 2-2007 (IEEE 802.3aw), 10GBASE-T Corrigendum. IEEE 802.3ax, (IEEE P802.1AX) Link Aggregation Task Force. IEEE 802.3ay, (IEEE P802.3Rev) Maintenance #9 (Revision) Task Force. |
| IEEE 802.3an | 10GBASE-T, or IEEE 802.3an-2006, is a standard released in 2006 to provide 10 gigabit/second connections over unshielded or shielded twisted pair cables, over distances up to 100 metres (330 ft). |
| Latency | The amount of time it takes a packet to travel over a network from source to destination as it is momentarily stored, analyzed and then forwarded. Latency can be measured over a network, over a link, or through a silicon device. |
| LDPC | Low-Density Parity-Check code (LDPC code) is an error correcting code, a method of transmitting a message over a noisy transmission channel. LDPC coding is defined as part of the IEEE 802.3an 10GBase-T standard. |
| LED | light-emitting diode; generally utilized as low-energy indicators of status. |
| MDC | Management Data Input/Output, or MDIO, is a standard-driven, dedicated-bus approach that's specified in IEEE RFC802.3. The MDIO interface is implemented by two pins, an MDIO pin and a Management Data Clock (MDC) pin. |
| MDIO | Management Data Input/Output, or MDIO, is a standard-driven, dedicated-bus approach that's specified in IEEE RFC802.3. The MDIO interface is implemented by two pins, an MDIO pin and a Management Data Clock (MDC) pin. Chapter 22, the MDIO interface is defined in relationship to the accessing and modification of various registers within physical-layer (PHY) devices, and how they relate to connecting to media access controllers (MACs) in 1- and 10-Gbit/s Ethernet solutions. |
| NEXT | Near end crosstalk (NEXT) is interference between two pairs in one cable; as measured at the end of the cable nearest to the transmitter. |
| NIC | An abbreviation of the Network Interface Card, it provides an adapter interface in the form of an add-on card to the network. |
| OSI Model | The Open Systems Interconnection Reference Model (OSI Reference Model or OSI Model) is an abstract description for layered communications protocol design. There are seven described layers: Physical, Data Link, Network, Transport, Session, Presentation, Application. The Physical Layer is considered Layer 1. |
| PCI-SIG | Formed in 1992, PCI-SIG (originally formed as the Peripheral Component Interconnect Special Interest Group) is the industry organization chartered with the development and management of the PCI bus specification, the industry standard for a high-performance I/O interconnect to transfer data between a CPU and its peripherals. |
| PHY | PHY is an abbreviation for PHYsical Layer of the OSI model. The PHY's function is to connect the MAC (Media Access Controller) to the physical medium for transmission. Consisting a PCS and PMD subsets, the PHY layer provides an electrical and procedural interface to the transmission medium. |
| RJ-45 | An abbreviation of Registered Jack-45, this is a 8 position 8 contact (8P8C) plug most commonly used as an Ethernet connector. RJ45 defines the mechanical connection, while T568A/B define the wiring. |
| Router | A router is a network device operating at Layer 4 of the OSI model. |
| SGMII | The Serial Gigabit Media Independent Interface is a sequel of MII, a standard interface used to connect an Ethernet MAC-block to a PHY (Physical Layer Device). It is used for Gigabit Ethernet (contrary to Ethernet 10/100 for MII). It differs from GMII by its low-power and low pin count serial interface (commonly referred to as a SerDes). SGMII consists of 8 differential signal lines. |
| Short Reach Mode (SRM) | Short Reach Mode (SRM) is an optional subset of the IEEE 802.3an 10GBase-T specification. It was originally added as an option to trade reach for power, during the initial concerns of 10GBase-T power consumption at full reach. Short Reach Mode in 10GBase-T requires 30 meters reach over twisted-pair cabling, versus the full 100 meters reach the specification is capable of. |
| SPI | An abbreviation of Serial Peripheral Interface bus, is a synchronous serial data link standard that operates in full duplex mode (sometimes called a "four-wire" bus). |
| Switch | A switch connects network segments. Switches may operate at one or more OSI layers, including physical, data link, network, or transport. Ethernet switches are primarily utilized within the LAN (local area network). |
| T568A/B | A feature of TIA/EIA-568-B.1-2001, T568A/B defines the pin/pair assignments for 8P8C (see RJ45) 100-ohm balanced twisted-pair cabling, such as Category 3, Category 5/5e, and Category 6/6A unshielded twisted-pair (UTP) cables used for Ethernet copper transmission. The only difference between T568A and T568B is that pairs 2 and 3 (orange and green) are swapped. |
| THP | An abbreviation of Tomlinson-Harashima Precoding, THP is a "precoder", where the equalizer for the channel is placed in the transmitter. THP is utilized in the IEEE 802.3an 10GBase-T specification. |
| TIA TR-42.7 | A sub-committee of TIA (Telecommunications Industry Association ), TR-42.7 - Telecommunications Copper Cabling Systems develops and maintains generic standards primarily for balanced twisted-pair cabling systems. These standards cover balanced twisted-pair cable and associated connecting hardware specifications, including test procedures, performance requirements, and test instrument requirements. |
| Trellis Modulation | Also known as trellis coded modulation, or simply TCM, is a modulation scheme which allows highly efficient transmission of information. This form of modulation is utilized among 1 Gigabit Ethernet. |
| Twisted-Pair | Twisted pair cabling is a form of wiring in which two conductors are twisted together for the purposes of canceling out electromagnetic interference (EMI) from external sources. Unshielded and shielded twisted pair (UTP or STP) cabling are the primary medium over which Ethernet copper technology is transmitted. |
| UNH-IOL | An abbreviation for University of New Hampshire InterOperability Laboratory, UNH-IOL tests networking and data communications products. The UNH-IOL strives to maintain a strong reputation for independent, vendor-neutral testing of interoperability and conformance to technical standards. |
| X2 | X2 is a sequel standard to XENPAK that defines a type of fiber-optic or copper transceiver module which is compatible with the 10 Gigabit Ethernet (10GE) standard. |
| XAUI | XAUI is a standard for extending the XGMII (10 Gigabit Media Independent Interface) between the MAC and PHY layer of 10 Gigabit Ethernet. XAUI is pronounced "zowie", a concatenation of the Roman numeral X, meaning ten, and the initials of "Attachment Unit Interface". XAUI consists of 4 differential lanes of 3.125 Gbps each. |
| XENPAK | XENPAK is a standard that defines a type of fiber-optic or copper transceiver module which is compatible with the 10 Gigabit Ethernet (10GE) standard. |
| XGMII | 10 Gigabit Media Independent Interface (X refers to roman numeral ten) is a standard for connecting full duplex 10 Gigabit Ethernet ports on a printed circuit board. It is composed from two 32-bits datapaths (Rx & Tx) and two 4-bits control flows (Rxc & Txc), operating at 156.25 MHz. |