ICND 1

100BASEFX is a version of Fast Ethernet over optical fiber. It uses a 1300 nm nearinfrared (NIR) light wavelength transmitted via two strands of optical fiber, one for receive (RX) and the other for transmit (TX). Maximum length is 412 metres (1,350 ft) for halfduplex connections (to ensure collisions are detected), and 2 kilometres (6,600 ft) for fullduplex over multimode optical fiber. 100BASEFX uses the same 4B5B encoding and NRZI line code that 100BASETX does. 100BASEFX should use SC, ST, LC, MTRJ or MIC connectors with SC being the preferred option. 

10Mbps baseband Ethernet specification using two pairs of twistedpair cabling (Categories 3, 4, or 5): one pair for transmitting data and the other for receiving data. 10BASET, which is part of the IEEE 802.3 specification, has a distance limit of approximately 328 feet (100 meters) per segment. 

thirdgeneration mobile network. Refers generically to a category of nextgeneration mobile networks, such as UMTS and IMT2000. *official* 

fourth generation of mobile phone mobile communications standards. 

fifthgeneration mobile network. 

acknowledgment. Notification sent from one network device to another to acknowledge that some event occurred (for example, the receipt of a message). 

access control list. A list kept by routers to control access to or from the router for a number of services (for example, to prevent packets with a certain IP address from leaving a particular interface on the router). 

Rating of the trustworthiness of a routing information source. Administrative distance often is expressed as a numerical value between 0 and 255. The higher the value, the lower the trustworthiness rating.