| ALG |
Application-Level-Gateway |
| AIN |
Advanced Intelligent Networks |
| BOF |
Birds of a Feather; IETF interest
groups |
| CDR |
Call Detail Record |
| CPL |
Call Processing Language |
| DTMF |
Dual Tone Multi-Frequency |
| ETSI |
European Telecommunications Standards
Institute |
| GLP |
Gateway Location Protocol |
| GSM |
Global System for Mobile communications |
| GSTN |
Global Switched Telephone Network |
| gwloc |
Gateway Location, also Gateway
Discovery (IETF work in progress) |
| IETF |
Internet Engineering Task Force |
| IN |
Intelligent Networks |
| IP |
Internet Protocol |
| IPDC |
IP Device Control (family of
protocols, IETF work in progress, see also MGCP) |
| IPT |
Internet Telephony |
| ISDN |
Integrated Services Digital Network |
| ISP |
Internet Service Provider |
| ITSP |
Internet Telephony Service Providers |
| ITU |
International Telecommunication
Union |
| IVR |
Interactive Voice Reponse |
| IXC |
Long Distance Carrier |
| LAN |
Local Area Network |
| LEC |
Local Exchange Carrier |
| LNP |
Local Number Portability |
| NAT |
Network Address Translation |
| MGCP |
merged SGCP and IPDC protocols
(IETF work in progress) |
| NNI |
Network-to-Network Interface
(of a signaling interface) |
| non-repudiation |
The inability of one entity involved
in a communication to deny having participated in
all or part of the communication. |
| OSP |
Open Settlement Protocol (ETSI/Tiphon) |
| POTS |
Plain Old Telephone System, Pretty
Old Telephone System |
| PSTN |
Public Switched Telephone Network |
| QoS |
Quality of Service |
| R&D |
Research and Development |
| RTCP |
RTP Control Protocol |
| RTP |
Real-Time Transport Protocol |
| RTSP |
Real-Time Streaming Protocol |
| SAP |
Session Announcement Protocol |
| SDP |
Session Description Protocol |
| SGCP |
Simple Gateway Control Protocol
(IETF work in progress, see MGCP) |
| SIP |
Session Initiation Protocol |
| SS7 |
Signaling System Nr. 7 (NNI telcos'
signaling system) |
| Tiphon |
Telecommunications and Internet
Protocol Harmonization over Networks (ETSI project) |
| UNI |
User-to-Network Interface (of
a signaling interface) |
| VoIP |
Voice over IP |
| VON |
Voice over Net |
| VRU |
Voice Response Unit |
| ADPCM |
Adaptive Differential PCM (codec) |
| CELP |
Codebook Excited Linear Predictive
Coding (codec) |
| CSA-CELP |
Conjugate-Structure-Algebraic-Celp
(codec) |
| G.711 |
64 kbps PCM half-duplex codec
(high quality, high bandwidth, minimum processor
load) |
| G.723.1 |
6.4/5.3 kbps MP-MLQ codec
(low quality, low bandwidth, high processor load
due to the compression)
Note:
A summary of ITU-T Speech / Audio Codecs is
available at the PictureTel's site. |
| G.726 |
40/32/24/16 ADPCM codec (good
quality, medium bandwidth, low processor load)
Note: A
summary of ITU-T Speech / Audio Codecs is available
at the PictureTel's site. |
| G.728 |
16 kbps LD-CELP codec (medium
quality, medium bandwidth, very high processor load)
Note: A
summary of ITU-T Speech / Audio Codecs is available
at the PictureTel's site. |
| G.729 |
8 kbps ACELP codec (medium quality,
low bandwidth, high processor load)
Note: A
summary of ITU-T Speech / Audio Codecs is available
at the PictureTel's site. |
| gatekeeper |
an H.323 entity on the LAN which
provides address translation and controls access
to the LAN for H.323 terminals, gateways and MCUs |
| gateway |
an endpoint on the LAN which
provides for RT 2-way communications between
H.323 Terminal on the LAN and other ITU terminals
(ISDN, GSTN, ATM, ...) on WAN or to another H.323
gateway |
| H.225 |
protocols (RAS, RTP/RTCP, Q.931
call signaling) and message formats of the H.323
are covered in this standard |
| H.245 |
protocol for capability negotiation,
messages for opening and closing channels for media
streams, etc. (i.e. media signaling) |
| H.323 |
an umbrella standard for audio/video
conferencing over unreliable networks; architecture
and procedures are covered by this standard; H.323
relies on H.225 and H.245 |
| LD-CELP |
Low -Delay-CELP (codec) |
| MC |
The Multipoint Controller provides
the capability negotiation with all terminals taking
part in a multipoint conference. |
| MCU |
The Multipoint Control Unit is
an endpoint on the LAN which provides the capability
for 3 or more terminals and gateways to participate
in a multipoint conference. The MCU consists of
a mandatory MC and optional MPs. |
| MP |
The Multipoint Processor provides
for centralized processing (mixing, switching, ...)
of audio, video, and/or data streams in a multipoint
conference. |
| Q.931 |
ISDN call signaling protocol
(in H.323 scenario this protocol is encapsulated
in TCP and sent to the well known port 1720) |
| PCM |
Pulse Code Modulation (codec) |
| RAS |
Registration, Admission, Status
- management protocol between terminals and gatekeepers |
| T.120 |
data conference protocol |
