HP ProCurve Secure 7000dl Series Basic Management And Configuration Manual page 743

Table 2-2.
Physical
carrier
—
T1
T2
T3
T4
T5
DSX-1 Digital Signal X-1. A 1.544 Mbps T1 connection.
DTE Data Terminal Equipment. A device that controls data flowing to or from a
computer. On a Frame Relay network, the DTE receives data from the LAN in
the form of multiple protocol packets and encapsulates each packet into a
Frame Relay frame. The header of such a frame is called the Data Link
Connection Identifier (DLCI) and contains the frame's ultimate destination.
See also DCE.
DTMF Dual Tone Multi-Frequency. The signal to the phone company that is generated
when ordinary telephone touch keys are pressed. In the United States, this is
known as "touch-tone" dialing.
DVB Digital Video Broadcasting. A suite of internationally accepted, open
standards for digital television maintained by the DVB Project, an industry
consortium with more than 300 members. The DVB standards use current,
existing satellite, cable and terrestrial infrastructures.
DVMRP Distance Vector Multicast Routing Protocol. An OSI Layer 3 multicast routing
protocol for use within a single AS. DVMRP generates a multicast routing table
and forwards packets accordingly. It uses Internet Group Management
Protocol (IGMP) messages to exchange information with other routers. For
more information, see RFC 1075 (at http://www.ietf.org/rfc/rfc1075.txt).
DWDM Dense Wavelength Division Multiplexing. A technology that puts data from
different sources together on fiber optic. Each signal is carried on its own
separate light wavelength, and up to 80 (and theoretically more) separate
wavelengths or channels of data can be multiplexed into a lightstream trans-
mitted on a single optical fiber. In a system with each channel carrying 2.5
Gbps, up to 200 billion bits can be delivered per second by the optical fiber.
Digital Signal X (DSX) hierarchy
DSD DSX interface DSO multiple
DS0 —
DS1 DSX-1
DS2 DSX-2
DS3 DSX-3
DS4 DSX-4
DS5 DSX-5
Appendix B: Glossary
T1 multiple
1 —
24 —
96 4
672 28
4032 168
8064 336
Transmission
rate
64 Kbps
1.544 Mbps
6.312 Mbps
44.736 Mbps
274.176 Mbps
560.160 Mbps
B-17