VoIP 101
The buzz for this new phone system technology is reaching a
fever pitch yet, many people still have limited knowledge. There
are many terms that you need to understand when searching for a
VoIP provider so that you may take advantage of this low cost
technology. I am going to list them here.
AS - A group of networks under mutual administration that share
the same routing methodology. An AS uses an internal gateway
protocol and common metrics to route Packets within the AS, and
uses an external gateway protocol to route packets to other AS.
ASP (Application Service Provider) An independent, third-party
provider of software-based services delivered to customers
across a wide area network (WAN).
ATA - Analog Telephone Adapter A device that connects between an
analog telephone and an Internet connection port, and allows you
to use a standard phone to make and receive VoIP calls over the
Internet.
Average Hold Time - The average length of time between the
moment a caller finishes dialing and the moment the call is
answered or terminated
Bandwidth The maximum data carrying capacity of a transmission
link. For networks, bandwidth is usually expressed in bits per
second (bps).
Broadband Descriptive term for evolving digital technology that
provides consumers a single switch facility offering integrated
access to voice, high-speed data service, video demand services,
and interactive delivery services.
Codec - Short for coder/decoder, a piece of hardware or software
that automatically encodes/compresses and decodes/decompresses
voice signal data packets. A codec is used to minimize bandwith
usage while preserving voice quality. Although many proprietary
compression schemes exist, VoIP networks typically incorporate
at least one of several standardized audio CODECs for the sake
of interoperability.
Compression compression is used at anywhere from 1:1 to 12:1
ratios in VOIP applications to consume less bandwidth and leave
more for data or other voice/fax communications. The voice
quality may decrease with increased compression ratios.
Find-me/Follow-me Lying at the heart of the "unified messaging"
or "ubiquitous communication" concept, Find me/Follow me is a
feature that routes incoming calls to a user no matter where he
or she roams or what type of device is being used (home,
business or mobile phone). This "presence" feature, which rings
multiple phones simultaneously, is offered by many IP PBXs and
some hosted services. The feature is typically activated by
pressing a softkey.
Firewall A system designed to prevent unauthorized access to or
from a private network. Firewalls can be implemented as
hardware, software, or a combination of both. All messages
entering or leaving the intranet pass through the firewall,
which examines each message and blocks those that do not meet
the security criteria specified on the firewall.
FXO - Foreign Exchange Office. A device that connects with a
Central Office (CO) or PSTN analog line.
FXS - Foreign Exchange Station. A device that connects with an
"end-user" device such as a telephone or fax machine.
Gatekeeper - The central control entity that performs management
functions in a Voice and Fax over IP network and for multimedia
applications such as video conferencing. Gatekeepers provide
intelligence for the network, including address resolution,
authorization, and authentication services, the logging of Call
Detail Records, and communications with network management
systems.
Gatekeepers control bandwidth, provide interfaces to existing
legacy systems, and monitor the network for engineering purposes
as well as for real-time network management and load balancing,
. Internet Telephony - Any method of transmitting voice over the
internet. A multimedia PC with special client software will
digitalize your voice.
IP PBX - IP Private Branch Exchange. A business phone system
that offers advanced phone services between VoIP and PSTN
networks, such as music-on-hold, automatic call-routing,
voicemail, and call transfer.
IP phone - also called an Internet phone or broadband phone. An
IP phone plugs into a broadband Internet connection to make and
receive VoIP calls over the Internet.
Packet - A logically grouped unit of data. These packets of data
are distributed over the internet, and then are de-constructed
to voice when they reach their destination.
PSTN - Public-Switched Telephone Network, is the commonly-known
telephone network. PSTN is a circuit-switched network.
PSTN Failover - an optional port on an IP phone or ATA device
that connects to the PSTN network in case your Internet
connection or electrical power goes down. This configuration
requires you to have a regular telephone line and service.
Route - A set of parameters predefined by Voip provider to
facilitate routing of traffic between the Gateways/Gatekeepers
controlled by a Voip provider Member either via ownership or via
a partnership with the owner. Along with specifying other
parameters, a Voip provider Member using the Gatekeeping Service
assigns to a Route values specifying the details of both
originating and terminating Gateways/Gatekeepers.
SIP - Session Initiation Protocol. One of the newer, more common
signaling protocols used for VoIP.
Softphone - a "software" phone on a PC that can send and receive
calls over the Internet.
VoIP - Voice over Internet Protocol, which is a technology that
allows you to make and receive phone calls and faxes over the
Internet instead of through the telephone or cellular network.
VoIP Gateway - device that converts analog voice signals to
digital IP packets for communication over an Ethernet (LAN or
WAN) network.
VSP - VoIP Service Provider
In order to use VoIP, both sender and receiver need to have a
broadband connection. This is a high-speed Internet connection
usually provided by cable or a DSL modem. Broadband modems are
usually used to connect computers to the Internet, but in the
case of VoIP, computers are not necessary, because now there are
telephones that connect directly.