Topologies
What are network topologies?
Network Topologies.
Network topologies refer to the layout of a network. How different nodes are connected to each other and how they communicate is determined by the network’s topology. Topologies are either physical (the physical layout of devices on a network) or logical (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).
Mesh Topology.
In a mesh network, devices are connected with many redundant interconnections between network nodes. In a true mesh topology every node has a connection to every other node in the network. There are two types of mesh topologies:
Full mesh topology occurs when every node has a circuit connecting it to every other node in a network. Full mesh is very expensive to implement but yields the greatest amount of redundancy, so in the event that one of those nodes fails, network traffic can be directed to any of the other nodes. Full mesh is usually reserved for backbone networks.
Partial mesh topology is less expensive to implement and yields less redundancy than full mesh topology. With partial mesh, some nodes are organized in a full mesh scheme but others are only connected to one or two in the network. Partial mesh topology is commonly found in peripheral networks connected to a full meshed backbone.
Star topology
In a star network devices are connected to a central computer, called a hub. Nodes communicate across the network by passing data through the hub.
Main Advantage: In a star network, one malfunctioning node doesn't affect the rest of the network.
Main Disadvantage: If the central computer fails, the entire network becomes unusable.
Bus topology
In networking a bus is the central cable -- the main wire -- that connects all devices on a local-area network (LAN). It is also called the backbone. This is often used to describe the main network connections composing the Internet. Bus networks are relatively inexpensive and easy to install for small networks. Ethernet systems use a bus topology.
Main Advantage: It's easy to connect a computer or device and typically it requires less cable than a star topology.
Main Disadvantage: The entire network shuts down if there is a break in the main wire and it can be difficult to identify the problem if the network shuts down.