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Telecommunications network

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(Redirected from Communication networks)

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,[1] and the wireless radio networks of cell phone telecommunication providers.

Network structure

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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):

Data networks

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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:

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.[2]
  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.[2]
  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.[2]

Data center networks also rely highly on TCP/IP for communication across machines. They connect thousands of servers, are designed to be highly robust, provide low latency and high bandwidth. Data center network topology plays a significant role in determining the level of failure resiliency, ease of incremental expansion, communication bandwidth and latency.[3]

Capacity and speed

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In analogy to the improvements in the speed and capacity of digital computers, provided by advances in semiconductor technology and expressed in the bi-yearly doubling of transistor density, which is described empirically by Moore's law, the capacity and speed of telecommunications networks have followed similar advances, for similar reasons. In telecommunication, this is expressed in Edholm's law, proposed by and named after Phil Edholm in 2004.[4] This empirical law holds that the bandwidth of telecommunication networks doubles every 18 months, which has proven to be true since the 1970s.[4][5] The trend is evident in the Internet,[4] cellular (mobile), wireless and wired local area networks (LANs), and personal area networks.[5] This development is the consequence of rapid advances in the development of metal-oxide-semiconductor technology.[6]

See also

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References

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  1. ^ "Telecommunication Network - Types of Telecommunication Networks". Archived from the original on 2014-07-15. Retrieved 2014-07-14.[self-published source?]
  2. ^ a b c "Metropolitan Area Network (MAN)". Erg.abdn.ac.uk. Archived from the original on 2015-10-10. Retrieved 2013-06-15.
  3. ^ Noormohammadpour, Mohammad; Raghavendra, Cauligi (28 July 2018). "Datacenter Traffic Control: Understanding Techniques and Tradeoffs". IEEE Communications Surveys & Tutorials. 20 (2): 1492–1525. arXiv:1712.03530. doi:10.1109/COMST.2017.2782753. S2CID 28143006.
  4. ^ a b c Cherry, Steven (2004). "Edholm's law of bandwidth". IEEE Spectrum. 41 (7): 58–60. doi:10.1109/MSPEC.2004.1309810. S2CID 27580722.
  5. ^ a b Deng, Wei; Mahmoudi, Reza; van Roermund, Arthur (2012). Time Multiplexed Beam-Forming with Space-Frequency Transformation. New York: Springer. p. 1. ISBN 9781461450450.
  6. ^ Jindal, Renuka P. (2009). "From millibits to terabits per second and beyond – over 60 years of innovation". 2009 2nd International Workshop on Electron Devices and Semiconductor Technology. pp. 1–6. doi:10.1109/EDST.2009.5166093. ISBN 978-1-4244-3831-0. S2CID 25112828. Archived from the original on 2019-08-23. Retrieved 2019-10-14.