A telecommunications network is a group of nodes interconnected by telecommunications links that are used to exchange messages between the nodes. The links may use a variety of technologies based on the methodologies of circuit switching, message switching, or packet switching, to pass messages and signals. Multiple nodes may cooperate to pass the message from an originating node to the destination node, via multiple network hops. For this routing function, each node in the network is assigned a network address for identification and locating it on the network. The collection of addresses in the network is called the address space of the network. Examples of telecommunications networks include computer networks, the Internet, the public switched telephone network (PSTN), the global Telex network, the aeronautical ACARS network, and the wireless radio networks of cell phone telecommunication providers. Network 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 data plane (also user plane, bearer plane, or forwarding plane) carries the network's users' traffic, the actual payload. The control plane carries control information (also known as signaling). The management plane carries the operations, administration and management traffic required for network management. The management plane is sometimes considered a part of the control plane. Data networks Data networks are used extensively throughout the world for communication between individuals and organizations. Data networks can be connected to allow users seamless access to resources that are hosted outside of the particular provider they are connected to. The Internet is the best example of the internetworking of many data networks from different organizations. Terminals attached to IP networks like the Internet are addressed using IP addresses. Protocols of the Internet protocol suite (TCP/IP) provide the control and routing of messages across the and IP data network. There are many different network structures that IP can be used across to efficiently route messages, for example: Wide area networks (WAN) Metropolitan area networks (MAN) Local area networks (LAN) There are three features that differentiate MANs from LANs or WANs: 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. 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