Cisco Systems UBR7225VXR specifications GL-3

	Glossary
DSU	Data Service Unit. Device used in digital transmission that adapts the physical interface on a DTE
	device to a transmission facility such as T1 or E1. The DSU is also responsible for such functions as
	signal timing. Often used with CSU, as in CSU/DSU.
DTE	Data terminal equipment. Device at the user end of a user-network interface that serves as a data
	source, destination, or both. DTE connects to a data network through a DCE device (for example, a
	modem) and typically uses clocking signals generated by the DCE. DTE includes devices such as
	computers, protocol translators, and multiplexers.
E
EIA	Electronic Industries Alliance.
EMI	Electromagnetic interference.
EPROM	Erasable programmable read-only memory.
ESD	Electrostatic discharge.
EuroDOCSIS	European Data-over-Cable Service Interface Specifications.

F

Fast Ethernet

FEC

Flash memory

FRU

Any of a number of 100-Mbps Ethernet specifications. Fast Ethernet offers a speed increase 10 times that of the 10Base-T Ethernet specification, while preserving qualities such as frame format, MAC mechanisms, and MTU. Existing 10Base-T applications and network management tools can be used on Fast Ethernet networks. The Fast Ethernet specification is based on an extension to the IEEE 802.3 specification.

Forward error correction.

Nonvolatile storage that can be electrically erased and reprogrammed so that software images can be stored, booted, and rewritten as necessary. Flash memory was developed by Intel and is licensed to other semiconductor companies

Field-replaceable unit. A component that can be removed from a network device and replaced in the field. Line cards, power modules, and fan modules are typically FRUs.

G

GPS Global positioning system.

H

H.323 VoIP network Protocol that supports VoIP.

	Cisco uBR7225VXR Universal Broadband Router Hardware Installation Guide
OL-17309-02		GL-3