Glossary

3G, short form of third generation, is the third generation of mobile telecommunications technology.

This is based on a set of standards used for mobile devices and mobile telecommunications use services and networks that comply with the International Mobile Telecommunications-2000 (IMT-2000) specifications by the International Telecommunication Union.

3G finds application in wireless voice telephony, mobile Internet access, fixed wireless Internet access, video calls and mobile TV.

3G telecommunication networks support services that provide an information transfer rate of at least 200 kbit/s. Later 3G releases, often denoted 3.5G and 3.75G, also provide mobile broadband access of several Mbit/s to smartphones and mobile modems in laptop computers. This ensures it can be applied to wireless voice telephony, mobile Internet access, fixed wireless Internet access, video calls and mobile TV technologies.

A new generation of cellular standards has appeared approximately every tenth year since 1G systems were introduced in 1981/1982.

Each generation is characterized by new frequency bands, higher data rates and non–backward-compatible transmission technology. The first 3G networks were introduced in 1998 and fourth generation "4G" networks in 2008.

Signal encoding method used in 100Base-TX/FX Fast Ethernet and FDDI standards. Four-bit binary values are encoded into 5-bit symbols.

4G, short for fourth generation, is the fourth generation of mobile telecommunications technology, succeeding 3G . A 4G system must provide capabilities defined by ITU in IMT Advanced. Potential and current applications include amended mobile web access, IP telephony, gaming services, high-definition mobile TV, video conferencing, 3D television, and cloud computing.

Two 4G candidate systems are commercially deployed: the Mobile WiMAX standard (first used in South Korea in 2007), and the first-release Long Term Evolution (LTE) standard (in Oslo, Norway and Stockholm, Sweden since 2009). It has however been debated if these first-release versions should be considered to be 4G or not, as discussed in the technical definition section below.

In the United States, Sprint (previously Clearwire) has deployed Mobile WiMAX networks since 2008, while MetroPCS became the first operator to offer LTE service in 2010. USB wireless modems were among the first devices able to access these networks, with WiMAX smartphones becoming available during 2010, and LTE smartphones arriving in 2011. 3G and 4G equipment made for other continents are not always compatible because of different frequency bands. Mobile WiMAX is not available for the European market as of April 2012.

A rule that mandates that between any two nodes on the network, there can only be a maximum of five segments,connected through four repeaters, or concentrators,and only three of the five segments may contain user connections.

Commonly referred to as a telco, CHAMP, or blue ribbon connector. Commonly found on telephone switches,66-blocks, 110-blocks, and 10Base-T Ethernet hubs and used as an alternate twisted-pair segment connection method. The 50-pin connector connects to 25-pair cables, which are frequently used in telephone wiring systems and typically meet Category 3. Some manufacturers also make Category 5e

A configuration used to test alien crosstalk in the lab whereby six disturber cables completely surround and are in direct contact with a central disturbed cable.Required testing for all CAT-6A cables by ANSI/TIA-568-C.2.

Connecting block used by voice-grade telephone installations to terminate twisted pairs. Not recommended for LAN use.

The 800 MHz EE+H3G combiner/diplexer

Signal encoding method used by the 1000Base-X Gigabit Ethernet standards.

Signal encoding method used in 100Base-T4 Fast Ethernet standard.

A flaw on an optical surface usually caused by an improperly polished termination end.

The loss of power (signal) in an optical fiber resulting from conversion of optical power (specific wavelengths of light energy into heat.Caused principally by impurities,such as water, ions of copper or chromium (transition metals), and hydroxyl ions, and by exposure to nuclear radiation. Expressed in dB/km (decibels per kilometer).Absorption and scattering are the main causes of attenuation(loss of signal) of an optical waveguide during transmission through optical fiber.

Used to describe the language interface standards for interconnection of operating systems, network elements,workstations, and alarm functions.

With respect to optical-fiber cable, the angle within which light can enter an optical fiber core of a given numerical aperture and still reflect off the boundary layer between the core and the cladding. Light entering at the acceptance angle will be guided along the core rather than reflected off the surface or lost through the cladding. Often expressed as the half angle of the cone and measured from the axis. Generally measured as numerical aperture (NA); it is equal to the arcsine. The acceptance angle is also known as the cone of acceptance,or acceptance cone. See also numerical aperture.

The cross section of an optical fiber is circular; the light waves accepted by the core are expressed as a cone. The larger the acceptance cone, the larger the numerical aperture(NA); this means that the fiber is able to accept and propagate more light.