Mesh topology – can actually change on the fly. No central device oversees a mesh network, and no set route is used to pass data back and forth between computers. Each computer includes everything it needs to serve as a relay point for sending information to any other computer on the network.
Star topology – all devices are connected to a central hub. Star networks are relatively easy to install and manage, but bottlenecks can occur because all data must pass through the hub.
Bus topology – all devices are connected to a central cable, called the bus or backbone. Bus networks are relatively inexpensive and easy to install for small networks.
Tree topology – it combines characteristics of linear bus and star topologies. It consists of groups of star – configured workstations connected to a linear bus backbone cable.
OSI 7 layers
1. application layer - this layer supports application and end-user processes.
2. presentation layer - this layer provides independence from differences in the representation by translating from application to network format and vice versa.
3. session layer - this layer establish, manages and terminates connections between applications.
4. transport layer - it provides transparent transfer of data bet. end system or host and is responsible for end-to-end error recovery and flow control.
5. network layer - it provides switching and routing of technologies, creating logical paths, known as virtual circuits, for transmiting data from node to node.
6. data link layer - data packets are encoded and decoded into bits it furnishes transmission protocol knowledge and management and handles error in the physical layer, flow control and frame.
7.7 physical layer -
