I took the given notes from Khairil Hafiz's blog. He responded to what I asked during our ICT class. Thanks, Khairil Hafiz. So guys, please read.
NETWORK TOPOLOGY
Introduction:
Arrangement and configuration of cables, computers and other peripheral devices is called network topology. Topology may be a physical or logical depending on the network. There are different types of topologies used in networking. These are bus topology, star topology, ring topology, tree topology, and hybrid or mix topology. Bus topology consists of backbone cable and nodes. Each node is connected with central cable. Bus topology is very easy, simple and inexpensive than other topologies. Star topology consists of central device called hub or connector. All computers in star topology are directly connected to central devices. All functions are control and manage by central device. Star topology is very easy to install but it is expensive due to the cost of central device. Tree topology is combination of star and bus topologies. Group of star configured computers are connected to a central cable or backbone cable like bus topology. This network is very easy to extend and facilities the organizations to meet their requirements. Tree topology is mostly supported by number of hardware and software manufacturers. In tree topology if central cable breaks then all the nodes goes down. Hybrid or Mix topology is combination of different topologies such as star bus topology, star of star, star wired ring, hybrid mesh.
source : http://www.blurtit.com/q655638.html
Bus Topology:
Bus networks (not to be confused with the system bus of a computer) use a common backbone to connect all devices. A single cable, the backbone functions as a shared communication medium that devices attach or tap into with an interface connector. A device wanting to communicate with another device on the network sends a broadcast message onto the wire that all other devices see, but only the intended recipient actually accepts and processes the message.
Ethernet bus topologies are relatively easy to install and don't require much cabling compared to the alternatives. 10Base-2 ("ThinNet") and 10Base-5 ("ThickNet") both were popular Ethernet cabling options many years ago for bus topologies. However, bus networks work best with a limited number of devices. If more than a few dozen computers are added to a network bus, performance problems will likely result. In addition, if the backbone cable fails, the entire network effectively becomes unusable.
Ring Topology:
In a ring network, every device has exactly two neighbors for communication purposes. All messages travel through a ring in the same direction (either "clockwise" or "counterclockwise"). A failure in any cable or device breaks the loop and can take down the entire network.
To implement a ring network, one typically uses FDDI, SONET or Token Ring technology. Ring topologies are found in some office buildings or school campuses.
Star Topology:
Many home networks use the star topology. A star network features a central connection point called a "hub" that may be a hub, switchor router. Devices typically connect to the hub with Unshielded Twisted Pair (UTP) Ethernet.
Compared to the bus topology, a star network generally requires more cable, but a failure in any star network cable will only take down one computer's network access and not the entire LAN. (If the hub fails, however, the entire network also fails.)
Tree Topology:
Tree topologies integrate multiple star topologies together onto a bus. In its simplest form, only hub devices connect directly to the tree bus, and each hub functions as the "root" of a tree of devices. This bus/star hybrid approach supports future expandability of the network much better than a bus (limited in the number of devices due to the broadcast traffic it generates) or a star (limited by the number of hub connection points) alone.
Mesh Topology:
Mesh topologies involve the concept of routes. Unlike each of the previous topologies, messages sent on a mesh network can take any of several possible paths from source to destination. (Recall that even in a ring, although two cable paths exist, messages can only travel in one direction.) Some WANs most notably the Internet, employ mesh routing.
A mesh network in which every device connects to every other is called a full mesh. As shown in the illustration below, partial mesh networks also exist in which some devices connect only indirectly to others.
source : http://compnetworking.about.com/od/networkdesign/a/topologies.htm
Bus networks (not to be confused with the system bus of a computer) use a common backbone to connect all devices. A single cable, the backbone functions as a shared communication medium that devices attach or tap into with an interface connector. A device wanting to communicate with another device on the network sends a broadcast message onto the wire that all other devices see, but only the intended recipient actually accepts and processes the message.
Ethernet bus topologies are relatively easy to install and don't require much cabling compared to the alternatives. 10Base-2 ("ThinNet") and 10Base-5 ("ThickNet") both were popular Ethernet cabling options many years ago for bus topologies. However, bus networks work best with a limited number of devices. If more than a few dozen computers are added to a network bus, performance problems will likely result. In addition, if the backbone cable fails, the entire network effectively becomes unusable.
Ring Topology:
In a ring network, every device has exactly two neighbors for communication purposes. All messages travel through a ring in the same direction (either "clockwise" or "counterclockwise"). A failure in any cable or device breaks the loop and can take down the entire network.
To implement a ring network, one typically uses FDDI, SONET or Token Ring technology. Ring topologies are found in some office buildings or school campuses.
Star Topology:
Many home networks use the star topology. A star network features a central connection point called a "hub" that may be a hub, switchor router. Devices typically connect to the hub with Unshielded Twisted Pair (UTP) Ethernet.
Compared to the bus topology, a star network generally requires more cable, but a failure in any star network cable will only take down one computer's network access and not the entire LAN. (If the hub fails, however, the entire network also fails.)
Tree Topology:
Tree topologies integrate multiple star topologies together onto a bus. In its simplest form, only hub devices connect directly to the tree bus, and each hub functions as the "root" of a tree of devices. This bus/star hybrid approach supports future expandability of the network much better than a bus (limited in the number of devices due to the broadcast traffic it generates) or a star (limited by the number of hub connection points) alone.
Mesh Topology:
Mesh topologies involve the concept of routes. Unlike each of the previous topologies, messages sent on a mesh network can take any of several possible paths from source to destination. (Recall that even in a ring, although two cable paths exist, messages can only travel in one direction.) Some WANs most notably the Internet, employ mesh routing.
A mesh network in which every device connects to every other is called a full mesh. As shown in the illustration below, partial mesh networks also exist in which some devices connect only indirectly to others.
source : http://compnetworking.about.com/od/networkdesign/a/topologies.htm
- Pak G-
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