The 10-Mbps baseband Ethernet specification that uses two pairs of twisted-pair cabling (Category 3 or 5): one pair for transmitting data and the other for receiving data.
C
carrier detect (CD)
Signal that indicates whether the G.SHDSL line is active.
crossover Ethernet cable
A cable that wires a pin to its opposite pin; for example, RX+ is wired to TX+. A crossover Ethernet cable connects two similar devices, such as two data terminal equipment (DTE) or data communications equipment (DCE) devices.
D
DRAM
Dynamic RAM. RAM that stores information that must be refreshed periodically in capacitors.
E
EMI
Electromagnetic interference. Interference by electromagnetic signals that can cause reduced data integrity and increased error rates on transmission channels.
ESD
Electrostatic discharge. A transfer of electrostatic charge between bodies of different electrostatic potentials, such as an operator and a piece of electrical equipment. ESD occurs when electronic components are improperly handled and can damage equipment and impair electrical circuitry. ESD is more likely to occur in the presence of synthetic fibers and dry atmosphere.
F
Flash memory
The nonvolatile storage that can be electrically erased and reprogrammed so that data can be stored, booted, and rewritten as necessary.
G
G.SHDSL
Symmetrical high-data-rate digital subscriber line technology that enables high-speed transmission over the "last mile" between the service provider and the customer site.
M
MDI
Media-dependent interface. A port on an Ethernet network device used to connect the device to the Ethernet network, usually through a hub or switch.
MDI-X
Media-dependent interface, crossover. A port on an Ethernet hub, such as the Cisco 1528 Micro Hub 10/100, that connects the Ethernet network devices through the MDI port to create a network.
S
SELV
Safety extra-low voltage. A secondary circuit that under normal conditions has a voltage less than 42.4V peak or 42 VDC. Under a single fault condition, this circuit should not exceed these values for longer than 0.2 second and should not exceed 71V peak or 120 VDC.
straight-through Ethernet cable
A cable that wires a pin to its equivalent pin. This cable typically connects a router to a hub. A straight-through Ethernet cable is the most common cable used.
T
TO HUB/TO PC button
With this button, you can connect hubs, servers, PCs, and workstations, using the yellow Ethernet (straight-through) cable instead of a crossover Ethernet cable, which you would need to supply. This button identifies the device that you connect to the router Ethernet port. Setting the button to the TO HUB position (in) indicates that you are connecting a hub; setting the button to the TO PC position (out) indicates that you are connecting a server, PC, or workstation.
