User Manual

Cisco High-Density Analog Voice and Fax Network Module
Glossary
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Cisco IOS Release 12.2(2)XT and 12.2(8)T
Glossary
ATM—Asynchronous Transport Mode.
adaptive jitter buffering—adaptive jitter buffer intelligently balances delay and packet loss through the
gateway for maximum call clarity and quality.
CAS—Channel Associated signaling. A signaling technique that uses the same facility path for both
voice and signaling traffic.
comfort noise generation—While using VAD, the DSP at the destination emulates background noise
from the source side, preventing the perception that a call is disconnected.
DSP—Digital Signal Processor. Specialized microprocessor used for voice processing.
DTMF—dual tone multifrequency. Tones used to send phone number digits to and from a switch. DTMF
tones identify the number 0-9 and the * and # symbols.
ground start— Used for PBX and other services that must have ground signal to indicate when a dial
tone is applied by the serving switching system or is used to avoid glare. Advantages of Ground-Start:
minimizes the possibility of glare; provides Far-End Disconnect Supervision (for example, the remote
user can disconnect, and local FXO can be made aware of this and also disconnect).
H.323—ITU-T standard for multimedia logical channels.
NM-HDA—High-Density Analog Voice and Fax Network Module.
immediate start— In the immediate start protocol, the originating side does not wait for a wink before
sending addressing information. After receiving addressing digits, the terminating side then goes
off-hook for the duration of the call. The originating endpoint maintains off-hook for the duration of the
call.
loop start— Use the loop signaling format. On-hook and off-hook states are represented by the absence
or presence of current in the loop. Loop start is used for signaling over subscriber line circuit, or loop.
Loop start might have two problems of glare state and no disconnect recognition.
NM—network module.
PSTN—Public Switched Telephone Network.
RAS—Registration Admissions and Status Protocol.
SAS—Signaling Access Server. Also called a signaling controller. A server based on TransPath system
technology that interfaces between the NAS and the SS7 signaling network.
SVC—switched virtual circuit.
T1—24 64kpbs timeslots on a 1.544 Mbps serial interface.
VA D — Voice Activity Detection (silence suppression) Bandwidth on the packet network is used only
when someone is speaking.
Wink—TelCo terminology for a specific transition of the signaling bits on a T1 line. If the originating
state of the signaling bits indicates on-hook, then a “wink” is an on-hook to off-hook to on-hook
transition. The timing of the wink and the values of the signaling bits for on-hook and off-hook can
depend on signaling type.
Wink Start—The terminating side responds to an off-hook from the originating side with a short wink.
This wink tells the originating side that the terminating side is ready to receive addressing digits. After
receiving addressing digits, the terminating side then goes off-hook for the duration of the call.