Editing Network topology (section)

{{Short description|Arrangement of a communication network}}
{{about|the topology of communication networks|the topology of electrical networks|Topology (electrical circuits)|the topology of transport networks|Transport topology|notion of network from general topology|Base (topology)}}
{{Network Science}}

'''Network topology''' is the arrangement of the elements ([[Data link|links]], [[Node (networking)|nodes]], etc.) of a communication network.<ref name="Groth">{{Cite book
|last =Groth
|first = David
|author2=Toby Skandier
|title = Network+ Study Guide, Fourth Edition
|publisher = Sybex, Inc.
|year =  2005
|isbn = 0-7821-4406-3
}}</ref><ref name="atis">{{Cite web|author=ATIS committee PRQC|title=mesh topology|url=http://www.atis.org/glossary/definition.aspx?id=3516|url-status=dead|archive-url=https://archive.today/20130414061003/http://www.atis.org/glossary/definition.aspx?id=3516|archive-date=April 14, 2013|access-date=2008-10-10|work=ATIS Telecom Glossary 2007|publisher=[[Alliance for Telecommunications Industry Solutions]]}}</ref> Network topology can be used to define or describe the arrangement of various types of telecommunication networks, including [[command and control]] radio networks,<ref name="GrantC2"/> industrial [[Fieldbus|fieldbusses]] and [[computer networks]].

Network topology is the [[topological]]<ref name="Chiang04">{{cite journal|last1=Chiang|first1=Mung|last2=Yang|first2=Michael|year=2004|title=Towards Network X-ities From a Topological Point of View: Evolvability and Scalability|url=http://www.cs.unm.edu/~karlinjf/papers/allerton.pdf|url-status=dead|journal=Proc. 42nd Allerton Conference|archive-url=https://web.archive.org/web/20130921053241/http://www.cs.unm.edu/~karlinjf/papers/allerton.pdf|archive-date=September 21, 2013}}</ref> structure of a network and may be depicted physically or logically. It is an application of [[graph theory]]<ref name="GrantC2">{{cite book|title=Network Topology in Command and Control |editor= Grant, T. J. |series= Advances in Information Security, Privacy, and Ethics |publisher= IGI Global |year= 2014 |url= https://books.google.com/books?id=zBOXBQAAQBAJ |pages= xvii, 228, 250 |isbn= 9781466660595 }}</ref> wherein communicating devices are modeled as nodes and the connections between the devices are modeled as links or lines between the nodes. '''Physical topology''' is the placement of the various components of a network (e.g., device location and cable installation), while '''logical topology''' illustrates how data flows within a network. Distances between nodes, physical interconnections, [[transmission rate]]s, or signal types may differ between two different networks, yet their logical topologies may be identical. A network's physical topology is a particular concern of the [[physical layer]] of the [[OSI model]]. 

Examples of network topologies are found in [[local area network]]s ([[LAN]]), a common computer network installation. Any given node in the LAN has one or more physical links to other devices in the network; graphically mapping these links results in a geometric shape that can be used to describe the physical topology of the network. A wide variety of physical topologies have been used in LANs, including [[ring network|ring]], [[bus network|bus]], [[mesh network|mesh]] and [[star network|star]].  Conversely, mapping the [[Traffic flow (computer networking)|data flow]] between the components determines the logical topology of the network.  In comparison, [[Controller Area Network]]s, common in vehicles, are primarily distributed [[control system]] networks of one or more controllers interconnected with sensors and actuators over, invariably, a physical bus topology.