A phone system which allows not only onsite/offsite connections (eg. incoming and outgoing calls) but also onsite/onsite connections (eg. calls to extensions, call transfers, etc.). A PABX (sometimes called a PBX) is the actual phone system box. The handsets are the extensions. Common features of a PABX are: extension dialling, call transfer, call holding, conference calling, DID (Direct In Dialling), CND (Calling Number Display) overwriting, CID (Caller ID) pass-through, and LCR (Least Cost Routing). PABXs superseded KTSs (Key Telephone Systems).

Usually IP networks, data travels over the communications links as data packets. This enables links to be shared (carrying packets from multiple sources). IP networks can often show reduced network (switching) errors, but may introduce delays to packets when the communications channels are congested.

These protocols, of which the IP is the most common, are rules for formatting the breakdown of data into discrete packages, called packets. A data packet is composed of a header and a small part of the data. The header is generated by the protocol and contains the address of the packet`s destination. Packet switching is very efficient because at each stage of routing only the address (or part of the address) is read and not the entire data packet. (A useful analogy is a mail sorting room: the letter (data) is not read, just the relevant part of the address.) Because packets all have an address, they may be sent via any available communications channel and data from multiple sources may be sent via the same communications channel. This is another efficiency gain.

The act of routing a data packet and also deciding Most commonly, the act of routing IP packets through the internet. Packet switching not only includes the act of redirection of each packet, but also manages the decision making of each routing node.

Mobile Technology: Largely superseded technology whereby a wireless device could receive text messages to a small device called a pager. SMS allows two-way text messaging, and has largely replaced Paging. Additional feature of some PABX systems which allows

See PABX

Early version of PDAs. See PDA.

A small mobile hand-held device that provides computing and information storage and retrieval capabilities for personal or business use, often for keeping schedule calendars and address book information handy

Hand-held mobile device which not only acts as a mobile phone, but may also have features such as: email capable, organiser, diary, web enabled (either through WAP or HTML), SMS capable, etc. PDAs use QWERTY keyboards or other.

The times of day and days of the week, when communications traffic is expected to be high, when compared with other times.

Rates applied during Peak Periods. Normal rate plan pricing from Service Providers. Peak rates are only implicitly referred to through the use of terms such as Off Peak and Economy rates.

Use of a system (often involving multiplexors) which use less copper pairs than other systems to create the same telecommunications capacity. For instance, some pair gain systems are capable of delivering 45 phone lines over one copper pair - in theory, there is a gain of 44 pairs available for other use. Pair gain systems are extremely useful where buildings have no more available copper lines.

Typically this is a prepaid charge card, which allows calls to be made from most Landline services. Also called a Calling Card. Distinct from a TeleCard, which is not prepaid and will be billed back to the selected fixed service account.

The agreed service provided to a mobile or landline subscriber. Includes call rates, monthly access fees, included calls and special offers.

Utility for testing if a particular network destination is available on a network connection. It sends an ICMP (Internet Control Message Protocol) echo request and waits for a response. PING tests are commonly used to debug network connections. (A convenient analogy is from submarine use; where a submarine might send a sonar pulse (a ping) towards a target and wait for an echo. A sonar echo provides targeting information.)

Amalgamating the terms Pictures (PIX) and Element (EL). Images and video may be digitised and the smallest element is called a Pixel. Image resolution is defined as Pixels per inch.

Defined by billing method, Plan Types is a common usage term. Plans may be Prepaid or Post-paid. Prepaid mobile phone plans typically are casual plans, with higher rates and credit must be paid up-front. Buying of mobile usage credit can be done with credit card or cash: online, in shops or over the phone. Post-paid mobile accounts are typically mobile phone accounts under contract, with lower rates and are paid on invoicing of usage. Post-paid plans may be paid by direct debit, credit card or `on account`.

Incoming call alert (also used for incoming SMS and email alerts) polyphonic ringtones produce a more `natural` sound than their predecessor monophonic ringtones. Polyphonic ringtones (often use MIDI files to) produce up to 24 simultaneous notes. This blending of notes creates a more natural sound.

Landlines: Location where a carrier provides connection into a local exchange. Often in use in Australia, where Telstra commonly provides the Last Mile connection (from the premises to the exchange) but another provider carries the communications from the local exchange. Internet Connection: Location where a carrier provides connection into a local exchange. A PoP for dial-up internet is described as a connection which is available within a local call area. (See also MegaPoPs.) For broadband, a PoP is defined as a network node, which is available in the local exchange.

Email term to denote the protocol for the retrieval of email from a server. POP3 denotes POP version three. See also IMAP - another email retrieval protocol.

Post-paid mobile phone contracts are typically mobile phone accounts under contract, with lower rates than their prepaid counterparts, and are paid on invoicing of usage. Post-paid plans may be paid by direct debit, credit card or `on account`. On account means payment is not automated, but rather is invoiced for payment.

Traditional switched telephone system using copper lines.

Protocol for connection to a TCP/IP network. The internet is a TCP/IP network.

Early protocol for creation of VPNs (Virtual Private Networks). Flawed security. Extended by introduction of L2TP, which incorporated Microsoft`s PPTP and Cisco`s L2FA technology.

See PRI.