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Glossary of terms

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Access Aggregation Region (AAR):
The area served by a Point of Interconnect (PoI) located in an Aggregation Node (AN) and connected via Trunk Fibre to regional Fibre Access Node (FAN) sites. The backhaul from the regional FAN to the AN is termed Transit Backhaul.

Access Seekers
A generic term that refers to customers of NBN Co's network, be they Retail Service Providers (RSPs) or Wholesale Service Providers (WSPs).

Aggregated Ethernet Bitstream (AEB)
One of two Layer 2 bitstream products to be offered by NBN Co (the other being LEB - Local Ethernet Bitstream). The AEB product enables aggregated access to one or more Fibre Serving Areas (FSAs) via an aggregated link. The LEB product will not be available in locations where the AEB product is made available.

Aggregation Node (AN):
A facility that provides a Point of Interconnect to RSPs/WSPs for an Access Aggregation Region (AAR), comprising a number of regional Fibre Access Node (FAN) sites. Note that an AN will also have a co-located Fibre Access Node (FAN) site for it's local area.

Asymmetric Digital Subscriber Line (ADSL)
ADSL is a type of DSL broadband communications technology used for connecting to the Internet. ADSL allows more data to be sent over existing copper telephone lines (POTS), when compared to traditional modem lines.

Asynchronous Transfer Mode (ATM)
ATM is a standardised digital data transmission technology.

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Backhaul typically refers to the mid-to-long-distance transport of data from a series of disparate locations back to a more centralised location. This transport may involve some level of concentration (also referred to as aggregation).

Bandwidth refers to how fast data flows through the path that it travels to your computer. It is usually measured in kilobits, megabits or gigabits per second.

A 'bit' is a basic unit of information in computing, essentially a '1' or '0'. Bits per second (bps) is a common measure for data transmission speed. The speed in bps is equal to the number of bits transmitted or received each second. Larger units are often used to denote high data speeds: kbps (kilobits per second) being one thousand bits per second; mbps (megabits per second) being one million bits per second; and gbps (gigabits per second) being one thousand million bits per second.

A generic term often used to describe low-complexity data transmission products.

Broadband is a term used to refer to 'always on' high speed Internet. In the past, broadband services and technologies were defined in terms of a capability to transfer information at higher rates than traditional dial-up services. Today broadband is more commonly associated with the speeds equal to or greater than those provided by Asymmetric Digital Subscriber Line (ADSL), that is, a minimum download speed of 265 kbps and minimum upload speed of 64 kbps

A unit of storage measurement - a byte is made up of 8 bits. All information is stored as bits and bytes, which determine the size of the document, picture, video clip etc that you may wish to download or send via email.

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Customer Premises Equipment (CPE)
The computer, modem and wiring at a customer's premises.

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Distribution Fibre
The fibre between the Fibre Distribution Hub (FDH) and the Fibre Access Node (FAN), for both regional FANs and the metro FANs, as well as the connectivity between the non adjacent Fibre Serving Area Modules in the capital cities and the metro FANs. Distribution Fibre routes are designed in a ring structure to minimise the impact of any fibre break on consumer services as well as providing diverse paths for protected commercial point to point services.

Distribution Network
Refers to the network of Distribution Fibres.

A download is any activity that transfers data to your computer from another one. Viewing a web page is downloading, because all the words, pictures and links on that page have to be transferred to your computer and contributes to any download limits placed on your account by your Internet service provider. Other activities like retrieving emails, listening to music, watching a video or chatting online are also downloads.

Drop Fibre
The fibre from the Network Access Point (NAP) to the termination point at individual premises.

DSL - Digital subscriber line
DSL is a group of technologies, the most common being asymmetric digital subscriber line (ADSL). DSL uses your existing telephone line to deliver high-speed Internet access. It allows voice communication and high-speed data transmission on the same line at the same time.

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A common method of networking computers in a local area network (LAN) using a variety of forms of cabling. Ethernet supports retail service provider (RSP) service differentiation as a result of a ubiquitous interface. It facilitates competition and choice as is able to support multiple services and RSPs on the same physical interface, when necessary. It offers flexibility and substantial bandwidth. It supports security and grades of QoS.

Ethernet Aggregation Switch (EAS)

The equipment that provides aggregation of FSAs to an AN for each retail service provider (RSP) and wholesale service provider (WSP).

Ethernet Fanout Switch (EFS)
The equipment that provides port fanout/expansion between the Point of Interconnect (POI) and the Optical Line Terminal (OLT) for each retail service provider (RSP) and wholesale service provider (WSP).

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Fibre Access Node (FAN)
A facility that houses the active equipment providing services to a Fibre Serving Area (FSA).

Fibre Distribution Area (FDA)
The area served via a single Fibre Distribution Hub (FDH) which connects addresses to the serving FAN site(s) via Local Fibre.

Fibre Distribution Hub (FDH)
A facility that houses the optical splitters.

Fibre Serving Area (FSA)
The area served by a Fibre Access Node (FAN) site, which will be a cluster of Fibre Distribution Area (FDA). The FDAs will be connected via Distribution Fibre.

Fibre to the Building (FTTB)
All types of nbn™ network connections that utilise a physical line running to the premises are considered fixed line connections. An nbn™ Fibre to the building (FTTB) connection is generally used when we are connecting an apartment block or similar types of buildings to the nbn™ network. In this scenario we run a fibre optic line to the building communications room - we then use the existing technology in the building to connect to each apartment. The fibre node in the building communications room is likely to take the form of a secure cabinet. Each cabinet will allow the nbn™ network signal to travel over the optic fibre, to the existing network technology present in the building.

Fibre to the Node (FTTN)
An nbn™ Fibre to the node (FTTN) connection is utilised in circumstances where the existing copper network will be used to make the final part of the nbn™ network connection, from a nearby FTTN cabinet or micro-node to your premises. The fibre node is likely to take the form of a street cabinet. Each street cabinet will allow the nbn™ network signal to travel over optic fibre from the exchange to the cabinet, and connect with the existing copper network to reach your premises.

Fibre to the Premises (FTTP)
An nbn™ Fibre to the premises connection (FTTP) is used in circumstances where an optic fibre line will be run from the nearest available fibre node, to your premises. FTTP also requires an nbn™ network device to be installed inside your home. This device requires power to operate and can only be installed by an approved nbn™ Installer or service provider..

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Geocoded National Address File (GNAF)

The authoritative address index for Australia, produced by PSMA Australia Limited.

Gigabit Passive Optical Networking (GPON)
An optical-access system based on Internet Protocol (IP) that lets multiple homes or businesses in a neighbourhood share fibre from a service provider's central office.

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IP Addressing
Refers to the addressing scheme for the Internet Protocol.

Internet Service Provider (ISP)
An organisation that offers access to the Internet to its customer.

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Kilobits per second (Kbps)
Bits per second (bps) is a common measure for data transmission speed. The speed in bps is equal to the number of bits transmitted or received each second. kbps is kilobits per second is one thousand bits per second.

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Or delay refers to how much time it takes for data to get from one designated point to another.

Local Ethernet Bitstream (LEB)
One of two Layer 2 bitstream products to be offered by NBN Co (the other being AEB - Aggregated Ethernet Bitstream)

Local Fibre
The connection between the Fibre Distribution Hubs (FDHs) and the individual premises via a series of radial fibre cables containing Network Access Points (NAPs), then a Drop Fibre to the building.

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Megabyte (MB)
Megabyte is the term used to describe a unit of data. Most Internet access plans operate on an allowance of data being downloaded and/or uploaded. This allowance is usually measured in MB or GB (Gigabytes).

One Megabyte is equivalent to about one million bytes. In current usage, that is a small amount of data. A 20 to 30 page document containing only text can be about 1 MB in size. Photos from digital cameras (depending on how they are saved) can be 2 or 3 MB each. A short video clip can be anywhere from 4 to 8 MB in size.

Megabits per second (Mbps)
A megabit per second (Mbit/s or Mb/s or Mbps) is a unit of data transfer rate equal to 1,000,000 bits per second.

Multi Dwelling Unit (MDU)
Typically refers to blocks of flats, apartments etc.

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Network Access Point (NAP)
The NAP is the point on a local fibre cable where the drop cable is connected.

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Open Access Network (OAN)

The horizontally layered network architecture and business model that separates physical access to the network from service provisioning. The same OAN will be used by a number of different providers that share the investments and maintenance cost.

Open access networks can be used to deploy next-generation broadband networks in low population density areas where service providers cannot obtain a sufficient return on investment to cover the high costs associated with trenching, right-of-way encroachment permits, and the requisite network infrastructure. In contrast to traditional municipal networks where the municipality owns the network and there is only one service provider, the open access model allows multiple service providers to compete over the same network at wholesale prices. In theory, this allows service providers to make money in the short-term and the municipality or cooperative to recoup its costs over the long-term. The build-out and infrastructure is typically financed through low-cost bonds.

Optical Distribution Frame (ODF)
Refers to a patching frame for optical fibres.

Optical Line Terminal (OLT)
The terminal equipment to provide the Gigabit Passive Optical Network (GPON) signals to each of the Fibre Distribution Areas (FDAs).

Optical Network Terminal (ONT)
Refer to the NBN Co. termination point on each premises, for residential service providing (typically) 4 Ethernet, 1 telephone and 1 co-axial ports.

Open System Interconnection (OSI) Reference Model
OSI Reference Model or OSI Model is an abstract description for layered communications and computer network protocol design. It divides network architecture into seven layers - Application, Presentation, Session, Transport, Network, Data-Link, and Physical Layers.

OSI Layers
A layer is a collection of conceptually similar functions that provide services to the layer above it and receives service from the layer below it.

Optical Transport Platform (OTP)
The optical transmission equipment providing data transport between Fibre Access Node (FAN) sites.

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Passive Optical Network (PON)
PON is a point-to-multipoint, fibre to the premises network architecture in which unpowered optical splitters utilizing Brewster's angle principles are used to enable a single optical fibre to serve multiple premises, typically 32-128. A PON consists of an optical line terminal (OLT) at the service provider's central office and a number of optical network units (ONUs) near end users. A PON configuration reduces the amount of fibre and central office equipment required compared with point to point architectures.

Plain Old Telephone Service (POTS)
POTS refers to the standard telephone service. In contrast, telephone services based on high-speed, digital communication lines are not POTS. The main distinctions between POTS and non-POTS services are speed and bandwidth. POTS is generally restricted to about 52 Kbps.

Point of Interconnect (PoI)
The connection point that allows retail service providers (RSPs) and wholesale service providers (WSPs) to connect to NBN Co access capability.

Point-to-Point Fibre
In contrast to Passive Optical Network (PON), the provision of services to a premises by a non-shared fibre from the Fibre Access Node (FAN).

Post Office Protocol (POP-1)
This refers to the way that email software gets mail from a mail server. Accounts with an ISP will always have a POP account to enable you to send and receive emails.

2. Point of Presence. This usually means a town or location where a network can be connected.

Point to Point Protocol (PPP) is the most common protocol used to connect home computers to the Internet over standard telephone lines. Variations include Point to Point Protocol over ATM (PPPOA) and Point to Point Protocol over Ethernet (PPPOE ).

A formal description of message formats and the rules two computers must follow to exchange those messages. Protocols can describe low level details of machine to machine interfaces (e.g. the order in which bits are sent through a connection) or high level exchanges between programs (e.g. the way in which two programs transfer a file across the Internet).

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Quality of Service (QoS)
QoS refers to a wide range of networking technologies and techniques. The goal of QoS is to provide guarantees on the ability of a network to deliver predictable results. Network performance within the scope of QoS can include availability, bandwidth, latency and error rate.

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Retail Service Providers (RSPs)
The retail network service providers and application/content service providers are those that provide services to end users and have a direct customer relationship with the end users. Wholesale service providers do not have this relationship.

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Common in rural and remote areas, broadband satellite uses a home radio link and radio dish to bounce a signal off a satellite and down to an earth station. It's used for fast Internet access and sometimes phone calls.

One-way satellite connections utilise a satellite link to download data to the broadband user and a standard telephone connection for uploading data back to the Internet.

Two-way satellite connections use the satellite link to both upload and download information.

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Transit Fibre
Refers to the connection between Points of Interconnect (PoIs) in the Aggregation Nodes where the retail service providers connect to NBN, and the non-local FANs.

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Wave Division Multiplexing Passive Optical Network (WDM PON)
Refers to an emerging Passive Optical Network (PON) technology that will provide greater speed and capability.

Wholesale Service Provider (WSP)
See Retail Service Providers (RSPs)

While the specific technology used to provide wireless broadband services varies, each service provider uses radio frequencies to transmit and receive data between their customers and a local transmission point. Normally, this requires a number of base stations, similar to mobile phone towers, which transmit to customers who have a small transmitter/receiver connected to their computers or other digital devices.

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