Specifications

Glossary
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Cisco AS5800 Operations, Administration, Maintenance, and Provisioning Guide
DOC-7810814=
dial selective signaling (DSS)
A multipoint network in which the called party is selected by a prearranged dialing code.
dial tone (DT)
A tone indicating that automatic switching equipment is ready to receive dial signals.
dialing parity
A company that is not an affiliate of a local phone company is able to provide phone services in such a manner that customers
have the ability to route their calls automatically without the use of any access code.
digital transmission
Transmission of data, audio, or video messages in discrete codes generated by computers.
domain
The name of a computer or network on the Internet, specifically the characters to the right of the “@” sign, indicating the
organization and the type of organization (.mil=military; .org=nonprofit; .edu=educational institution; .com=commercial, etc.)
that operates that domain or the physical location of the computer (.ca=Canada, .uk=United Kingdom)
DS3
Digital signal level 3. Framing specification used for transmitting digital signals at 44.736 Mbps on a T3 facility. See also E3
and T3.
DS0 Channel
Digital Signal Level 0. A 56 or 64 kbit/s channel. The DS0 channels for the T1 also pass signaling information using
“robbed-bit” signaling.
duplex signaling (DS)
A long-range bidirectional signaling method using paths derived from transmission cable pairs. It is based on a balanced and
symmetrical circuit that is identical at both ends. This circuit presents an E&M lead interface to connecting circuits.
E
E3
Wide-area digital transmission scheme used predominantly in Europe. E3 carries data at a rate of 34.368 Mbps. See also DS3.
Compare with T3.
egress interface
Egress interfaces are network connections, or ports, used for outbound traffic flow.
EIA/TIA-232
Common physical layer interface standard, developed by EIA and TIA, that supports unbalanced circuits at signal speeds up
to 64 kbps. Closely resembles the V.24 specification. Formerly called RS-232.