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MOCET IP3022 SOHO IP Deskphone User Guide
7.2. Terminology
10/100BASE-T
It is a LAN transmission line specification stipulated by IEEE.
Transmission speed is 10 or 100 Mbps and the modulation technique
is base-band modulation. The cable uses unshielded twisted pair,
similar to a telephone wire. 10BaseT is an IEEE standard (802.3) for
operating 10 Mbps Ethernet networks (LANs) with twisted pair cabling
and a wiring hub.
802.1p
An IEEE standard for providing QoS using three bits (defined in
802.1q) to allow switches to reorder packets based on priority level.
802.1q
An IEEE standard for providing virtual LAN (VLAN) identification and
QoS levels. Three bits are used to allow eight priority levels, and 12
bits are used to identify up to 4,096 VLANs.
AGC
Automatic Gain Control is a feature of IP solutions units that allows the
units to automatically adjust the incoming voice signal to a user
defined level in dBm.
A-law
The PCM coding and compression standard used in Europe and in
areas outside of North America influence. A Law Encoding is the
method of encoding sampled audio waveforms used in 2.048Mbps, 30
channel PCM primary system known as E-carrier.
Auto answer
In telephone call control: The capability of a machine to answer a
ringing telephone without human intervention.
Autodial
In telephone call control: An auxiliary device for a telephone that
automatically dials any of a group of prerecorded telephone numbers.
Blocked Calls
Caused by an insufficient network facility that does not have enough
lines to allow calls to reach a given destination. May also pertain to a
call from an originating number that is blocked by the receiving
telephone number.
Call Completion The point at which a dialed number is answered.
Call Termination The point at which a call is disconnected.
CDR
In telephone call control: Call Detail Record for billing
IP Centrex
This service is offered by the LEC to the end user. The feature-rich
Centrex line offers the same features and benefits as a PBX to a
customer without the capital investment or maintenance charges. The
LEC charges a monthly fee to the customer, who must agree to sign a
term agreement. And the abive service is thru VoIP called IP centrex.
CO
Switching center for the local exchange carrier.
CODEC
The CODEC (CODER/DECODER) is a standard through which voice
information can be encoded into data or decoded back to voice
information. Both a Coder and Decoder are necessary on both sides
of the telephone call since telephone calls occur simultaneously in
both directions. Bandwidth is an extremely important factor in QOS
(Quality of Service). MOS (Mean Opinion Score) is an attempt to
make a quantifiable benchmark of voice quality. Below are examples
of the CODEC, bit rate and mean opinion score: G.711 (toll quality)
64K MOS=4.1, G.726 16K (32K) MOS =3.8, G.729AB (cell phone
quality) 8K MOS=3.7.
