This answer is not selected as best answer. This answer may not be sufficient for exam.
A computer network is a group of computers linked to each other that enables the computer to communicate with another computer and share their resources, data, and applications.
A network topology is the physical and logical arrangement of nodes and connections in a network. Nodes usually include devices such as switches, routers and software with switch and router features. Network topologies are often represented as a graph.
There are several types of topologies. For example, physical topologies include the following:
- Bus network. In the bus network topology, every node is connected in series along a single cable. This arrangement is found today primarily in cable broadband distribution networks.
- Star network. In the star network topology, a central device connects to all other nodes through a central hub. Switched local area networks based on Ethernet switches and most wired home and office networks have a physical star topology.
- Ring network. In the ring network topology, the nodes are connected in a closed-loop configuration. Some rings pass data in one direction only, while others are capable of transmission in both directions. These bidirectional ring networks are more resilient than bus networks since traffic can reach a node by moving in either direction. Metro networks based on Synchronous Optical Network technology are the primary example of ring networks.
- Mesh network. The mesh network topology links nodes with connections so that multiple paths between at least some points of the network are available. A network is considered to be fully meshed if all nodes are directly connected to all other nodes and partially meshed if only some nodes have multiple connections to others. Meshing multiple paths increases resiliency but also increases cost. However, more space is needed for dedicated links.
- Tree network. The tree network topology consists of one root node, and all other nodes are connected in a hierarchy. The topology itself is connected in a star configuration. Many larger Ethernet switch networks, including data center networks, are configured as trees.
- Hybrid network. The hybrid network topology is any combination of two or more topologies. Hybrid topologies typically provide exceptional flexibility, as they can accommodate a number of setups. For example, different departments in the same organization may opt for personalized network topologies that are more adaptable to their network needs.