A Topology is a usually schematic description of the arrangement of a network, including its nodes and connecting lines.
There are two basic categories of network typologies
- Physical topologies
- Logical topologies
The shape of the cabling layout used to link devices is called the physical topology of the network. This refers to the layout of cabling, the locations of nodes, and the interconnections between the nodes and the cabling
The logical topology, in contrast, is the way that the signals act on the network media, or the way that the data passes through the network from one device to the next without regard to the physical interconnection of the devices. A network's logical topology is not necessarily the same as its physical topology.
Network Topologies
Bus Topology:- A bus topology creates a network by connecting 2 or more hosts to a length of coaxial backbone cabling. In this topology, a terminator must be placed on the end of the backbone coaxial cabling - in Michael Meyer's Network+ textbook, he commonly compares a network to a series of pipes that water travels through. Think of the data as water; in this respect, the terminator must be placed in order to prevent the water from flowing out of the network.
BUS TOPOLOGY
Ring Topology:- A ring topology (more commonly known as a token ring topology) creates a network by arranging 2 or more hosts in a circle. Data is passed between hosts through a 'token.' This token moves rapidly at all times throughout the ring in one direction. If a host desires to send data to another host, it will attach that data as well as a piece of data saying who the message is for to the token as it passes by. The other host will then see that the token has a message for it by scanning for destination MAC addresses that match its own. If the MAC addresses do match, the host will take the data and the message will be delivered.
RING TOPOLOGY
Star Topology:-A star topology creates a network by arranging 2 or more host machines around a central hub. A variation of this topology, the 'star ring' topology, is in common use today. The star topology is still regarded as one of the major network topologies of the networking world. A star topology is typically used in a broadcast network, where a single information source communicates directly with multiple clients. An example of this is a radio station, where a single antenna transmits data directly to many radios.
STAR TOPOLOGY
Tree Topology:-A tree topology is so named because it resembles a binary tree structure from computer science. The tree has a "root" node, which forms the base of the network. The root node then communicates with a number of smaller nodes, and those in turn communicate with an even greater number of smaller nodes. An example of a tree topology network is the DNS system. DNS root servers connect to DNS regional servers, which connect to local DNS servers which then connect with individual networks and computers. For your personal computer to talk to the root DNS server, it needs to send a request through the local DNS server, through the regional DNS server, and then to the root server.this is the best example for tree topology.
TREE TOPOLOGY
Mesh topology:- A mesh topology creates a network by ensuring that every host machine is connected to more than one other host machine on the local area network. This topology's main purpose is for fault tolerance - as opposed to a bus topology, where the entire LAN will go down if one host fails. In a mesh topology, as long as 2 machines with a working connection are still functioning, a LAN will still exist.The mesh topology is still regarded as one of the major network topologies of the networking world.
MESH TOPOLOGY
Hybrid topology:- A hybrid topology, which is what most networks implement today, uses a combination of multiple basic network topologies, usually by functioning as one topology logically while appearing as another physically. The most common hybrid topologies include Star Bus, and Star Ring.
HYBRID TOPOLOGY
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