Telecommunications network

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A telecommunications network is a network of telecommunications links and nodes arranged so that messages may be passed from one part of the network to another over multiple links and through various nodes.

Telecommunications network links (including their endpoints or "nodes") may in turn be built out of hierarchical transmission systems.

Examples of telecommunications networks are:

• Computer network
• the Internet Network- The internet network is a global ‘network of networks’. The internet is connected via an Internet Service Provider (ISP) and then becomes part of a network. This network then connects to a larger corporate network that interconnects with several other similar networks through Network Access Points (NAPs).^[1][2]
• the Public switched telephone network
• the global Telex network
• the aeronautical ACARS network

Contents 1 Telecommunication Network Components 2 Types of Telecommunication Networks 2.1 Wide Area Network (WAN) 2.2 Metropolitan Area Network (MAN) 2.3 Campus Area Network (CAN) 2.4 Local Area Network (LAN) 2.5 Personal Area Network (PAN) 2.6 Virtual Private Network (VPN) 2.7 Client/Server Network 2.8 Network Computing 2.9 Peer-to-Peer Network 3 Structure 4 See also 5 References

Telecommunication Network Components

All telecommunication networks are made up of five basic components that are present in each network environment regardless of type or use. These basic components include terminals, telecommunications processors, telecommunications channels, computers, and telecommunications control software.

• Terminals are the starting and stopping points in any telecommunication network environment. Any input or output device that is used to transmit or receive data can be classified as a terminal component. ^[3]

• Telecommunications processors are support data transmission and reception between terminals and computers by providing a variety of control and support functions. (i.e. convert data from digital to analog and back) ^[3]

• Telecommunications channels are the way by which data is transmitted and received. Telecommunication channels are created through a variety of media of which the most popular include copper wires and coaxial cables. Fiber-optic cables are increasingly used to bring faster and more robust connections to businesses and homes. ^[3]

• In a telecommunication environment computers are connected through media to perform their communication assignments. ^[3]

• Telecommunications control software is present on all networked computers and is responsible for controlling network activities and functionality. ^[3]

Early networks were built without computers, but late in the 20th century their switching centers were computerized or the networks replaced with computer networks.

Types of Telecommunication Networks

In its most basic form a network is an interconnected system of things or people ^[4]. From a technical standpoint a network is a data communication system that interconnects computer systems at different sites ^[5], or the connection of two or more computers using a communications system ^[6]

Most networks can be classified into one of five different types. These include wide area networks (WAN), local area networks, (LAN), virtual private networks (VPN), client/server networks, network computing, and peer-to-peer networks.

Wide Area Network (WAN)

Any network that encompasses a large geographic area is referred to as a WAN or Wide Area Network. Many large businesses and government agencies use WANs to keep their employees and citizens connected as well as provide a quick and effective way to send and receive information. ^[3]

Metropolitan Area Network (MAN)

A MAN or Metropolitan Area Network is a network that covers a region, often a metropolitan area that is bigger than a Local Area Network and smaller than a Wide Area Network and consists of several interconnected LANs. This network often serves regional businesses that have several locations throughout the region or entire cities. With this configuration, a MAN often is then connected to larger WAN networks.^[7]

There are three features that differentiate MANs from LANs or WANs:

1. The area of the network size is between LANs and WANs. The MAN will have a physical area between 5 and 50 km in diameter.^[8]

2. MANs do not generally belong to a single organization. The equipment that interconnects the network, the links, and the MAN itself are often owned by an association or a network provider that provides or leases the service to others.^[9]

3. A MAN is a means for sharing resources at high speeds within the network. It often provides connections to WAN networks for access to resources outside the scope of the MAN. ^[10]

Campus Area Network (CAN)

A CAN or Campus Area Network is a network that is restricted to a small geographic area such as a building complex or a college campus. It is smaller than a Metropolitan Area Network but larger than a Local Area Network. The CAN incorporates several LANS and usually has connections to a MAN or WAN.^[11]

Local Area Network (LAN)

Similar in many ways to WANs; Local Area Networks or LANs are responsible for connecting computers in a much smaller limited physical area. A good example of a LAN would be a hotel's wireless Internet offering which is self-contained within their own facility. ^[3]

There are multiple standards for Local Area Networks. Examples include IEEE 802.3 (Ethernet), IEEE 802.11 (Wi-Fi) or ITU-T G.hn (using existing home wires, such as power lines, phone lines and coaxial cables).

Personal Area Network (PAN)

A Personal Area Network (PAN) is a network that is restricted to the area of a person's body. It is much smaller than Local Area Network. It typically incorporates ad hoc connections to other PANs or directly to BlueTooth devices.

Virtual Private Network (VPN)

Virtual Private Networks or VPNs are a type of network that builds off of the concept of a WAN however relies upon the internet and an encrypted connection mechanism to establish a secure environment for internal or external employees or customers. ^[3]

Client/Server Network

The Client-Server network architecture continues to be the main architectural choice for most enterprise network computing. In a client/server environment the client (i.e. PC) relies on a LAN to connect with a back office network server that is responsible for the connection, retrieval, and storage or data and other critical company or personal information. ^[3]

Network Computing

Network computing is a network architecture that has grown with the Internet and resulting connection speeds. In a network computing architecture a computer uses its web browser to connect to another network computer that actually is running the application. A good example of this architecture in use is Google Docs, or Microsoft Office online. Both services allow users the ability to login to Google or Microsoft servers respectively and work similarly to how it would be performed on their own computing environment. ^[3]

Peer-to-Peer Network

Peer to peer networks are now beginning to be realized for the positive benefits they provide and not as only used for the sharing of copyrighted material. Peer-to-peer networks can be separated into two major types: Central Server and Pure. ^[3]

In a central server environment one host server maintains all active connections and shared information. When information is requested the central server informs the user where they can receive the file and allows the connection directly to the other PC to download. The best example of this type was the original Napster file sharing service.

A pure peer-to-peer network type has no central server to maintain active users relies instead on the individual computers to seek out all other computers offering the same information being requested. A good example of this type would be BitTorrent software which allows small parts of information to be pulled from many sources which one completed compiles into the one file that is being downloaded.

Structure

In general, every telecommunications network conceptually consists of three parts, or planes (so called because they can be thought of as being, and often are, separate overlay networks):

• The Control Plane carries control information (also known as signalling).
• The Data Plane or User Plane carries the network's users' traffic.
• The Management Plane carries the operations and administration traffic required for network management.

See also

• Active networking
• Access network
• Core network
• Optical fiber
• Submarine communications cable
• MVNE
• MVNO
• Network node
• Network model
• Federation (information technology)

References