ATA

Analogue Telephone Adaptor
A hardware device that converts the signals from a standard analogue telephone into the digital signals that a VOIP device needs to communicate over the internet.

Asterisk

Asterisk is a complete PBX software. It runs on Linux and provides all of the features you would expect from a PBX and more. Asterisk does voice over IP in three protocols, and can interoperate with almost all standards-based telephony equipment using relatively inexpensive hardware. For more information, refer to www.asterisk.org

Broadband

Broadband is the next generation of internet connectivity that allows users to get fast access to any data on the internet. Broadband includes cable and ADSL internet connections. VoIP needs broadband to operate at a minimal Quality of Service that is acceptable to most people. Information about broadband is available on this site on the broadband page.

CID

Caller Identification
This is where the identity (number) of an incoming telephone caller is displayed on a compatable telephone handset . If the receiver of the telephone call knows the caller and has the caller's phone number programmed into their compatible handset, the name of the caller can also be displayed on the handset.

DHCP

The Dynamic Host Configuration Protocol (DHCP) is an internet protocol that automates the allocation of ip addresses for computers that use TCP/IP (and yours does otherwise you wouldn't be reading this).

DID

Direct Inward Dialling Number
This is a telephone number that you can give to other people to phone you. Not all VSPs will give you a DID. All DIDs in Australia are registered with Telstra, and Telstra charges VSPs $5.00 per month for each DID. The VSP will then charge you $5.00 if you want a DID. Not everyone that uses VoIP will need a DID (ie if you keep your normal PSTN phone number and only use VoIP for outgoing calls).

ENUM

Telephone Electronic Number Mapping is a system where anyone that has a PSTN phone or a DID can register their phone number on an international database of VoIP users. Whenever someone with a VoIP telephone service (from a participating VSP) calls a phone number using their VoIP service, their participating VSP first checks the ENUM database. Information about ENUM is available on this site on the e164.org page.

Firewall

A firewall protects your computer network from the internet by preventing network traffic communicating between each other. That's great to prevent malicious attacks however it can cause havoc if you are trying to get your ip telephone to work. All routers have a firewall built in. Information about routers is available on this site on the routers page.

IP Address

The Internet Protocol Address is a unique number that is used to identify a hardware device on a network (NB The biggest network in the world is the Internet itself). An IP address takes the form ###.###.###.### where # = any integer. IP Addresses are allocated by routers so that the router knows what hardware devices are connected to it.

Internet Service Provider (ISP)

A company (ie like Telstra BigPond, Optusnet) that provides internet service to a subscriber (ie you). An ISP physically connects to the internet by paying for a connection to one or more internet service providers. The ISP then allows you to connect to their network and in doing so connects you to the internet.

MAC Address

a 12 digit HEX number that uniquely identifies computer hardware that connects to the internet.

PBX

Private Branch Exchange

Port (telephone numbers)

Every telephone number in Australia is related to a particular telephone company. When you change your telephone company, you can take your telephone number with your by trans(port)ing the number with you. This service is available between Optus, Vodaphone, Telstra and Virgin, but is currently not available between VSPs.

POTS

Plain Old Telephone Network
Used interchangably with PSTN to describe the standard telephone network.

PSTN

Public Switched Telephone Network
This is the standard telephone network that we all grew up with (ie Telstra, Optus etc).

QoS

Quality of Serivice
Quality of Service is a software inclusion in many routers that allows the user to prioritise the upstream bandwidth for a particular device. In this way, you can give a device such as an ATA priority over other internet traffic so that the quality of the VoIP call is maintained. This is important because most broadband connections have a smaller upstream bandwidth than the downstream bandwith. Information about QoS is available on this site on the Routers page.

Router

A router is effectively a 'powerboard' for the internet. You can connect more than one internet device to your single internet connection. Almost certainly if you have started with broadband internet, and then decided to add VoIP to your suite of internet services, you will need to buy a router. Information about routers is available on this site on the routers page.

RTP

Real Time Protocol

SIP

Session Initiation Protocol is the world wide standard used to initiate voice and video connectivity between 2 or more users. SIP is the protocol used to 'invite (or ring)' another VOIP user to talk to you.

Skype

Skype is a PC based VoIP service that uses a propriatry protocol. This means that Skype users can only phone other Skype users, and they cannot make calls to the PSTN network. For more information go to http://www.skype.com/

Softphone

A software based telephone that allows your PC to act like a regular telephone handset. Engin has a softphone that can be used with its VoIP service.

STUN

Simple Traversal of UDP through NAT
Different routers handle NAT differently. Which method your router uses will have an impact on how your ATA needs to operate. Some ATAs have a STUN client built in. Therefore your ATA can send a message to a STUN server and get a response back. This process called Stunning will tell the ATA what the public IP address of the ATA is, and how the Router is passing packets between the ATA and the internet.

TDM

Time Division Multiplexing

VOIP

Voice Over Internet Protocol
VoIP is a protocol the specifies how data is sent and received across the internet. VoIP uses codecs to code and decode the analogue data from your microphone into digital packets of data . The data is first coded into packets (ie descreet snippets of your conversation), then trasmitted across the internet using the voice over internet protocol, and then decoded and joined together again back into the continuous conversation so the person on the other end can hear you normally.

VSP

VoIP Service Provider