Astrology
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(Redirected from Network topologies)
For other uses of “topology”, see topology (disambiguation).
Diagram of different network topologies.
Diagram of different network topologies.
Network topology is the arrangement or mapping of the elements (links, nodes, etc.) of a network, especially the physical (real) and logical (virtual) interconnections between nodes.[1] [2] [3]

Network topology is sometimes also refered to the study of the arrangement or mapping of the elements (links, nodes, etc.) of a network.
A local area network (LAN) is one example of a network that exhibits both a physical topology and a logical topology. Any given node in the LAN will have one or more links to one or more other nodes in the network and the mapping of these links and nodes onto a graph results in a geometrical shape that determines the physical topology of the network. Likewise, the mapping of the flow of data between the nodes in the network determines the logical topology of the network. It is important to note that the physical and logical topologies might be identical in any particular network but they also may be different.

Any particular network topology is determined only by the graphical mapping of the configuration of physical and/or logical connections between nodes. LAN Network Topology is, therefore, technically a part of graph theory. Distances between nodes, physical interconnections, transmission rates, and/or signal types may differ in two networks and yet their topologies may be identical[2].

Contents
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* 1 Classification of network topologies
o 1.1 Physical topologies
+ 1.1.1 Classification of physical topologies
# 1.1.1.1 Point-to-point
# 1.1.1.2 Bus
# 1.1.1.3 Star
# 1.1.1.4 Ring
# 1.1.1.5 Mesh
# 1.1.1.6 Tree (also known as hierarchical):
+ 1.1.2 Hybrid network topologies
o 1.2 Signal topology
o 1.3 Logical topology
+ 1.3.1 Classification of logical topologies
* 2 Daisy chains
* 3 Centralization
* 4 Decentralization
* 5 Hybrids
* 7 References
 Classification of network topologies
There are also three basic categories of network topologies:
* physical topologies
* signal topologies
* logical topologies
* new topology
The terms signal topology and logical topology are often used interchangeably even though there is a subtle difference between the two and the distinction is not often made between the two.

 Physical topologies
The mapping of the nodes of a network and the physical connections between them вЂ“ i.e., the layout of wiring, cables, the locations of nodes, and the interconnections between the nodes and the cabling or wiring system[1][3].

 Classification of physical topologies
 Point-to-point
The simplest topology is a permanent link between two endpoints. Switched point-to-point topologies are the basic model of conventional telephony. The value of a permanent point-to-point network is the value of guaranteed, or nearly so, communications between the two endpoints. The value of an on-demand point-to-point connection is proportional to the