I need some assistance with these assignment. the committee of national security services model Thank you in advance for the help! Many people emphasize issues such as viruses, Trojans, hacking, and spyware, thus overlooking physical security. They forget that physical security breaches can be conducted with limited or without the technical know-how on the attacker’s part. Natural disasters and accidents are part of the day- to- day life, thus inevitable (Rouse, 2005).
The Open System Interconnect model comprises seven layers: Application, presentation, session, transport, network, data link, and physical. The physical layer is the lowest layer of the model, and its functions include transmitting and receiving the bitstream that is unstructured and raw over a medium that is physical in nature. The physical layer describes the mechanical, electrical/ optical, and functional interfaces on the medium that is physical and carries the received signals for all higher layers. The physical layer helps encode data, attachment to the physical medium, transmission technology, and transmission on the physical medium (Rhee, 2003).
The data link layer ensures that the data transferred on the physical layer, from a node to another, is free from error. This enables the layers above it to be able to have an error-free transmission. To do this, the layer of data link provides an establishing and terminating link that ensures that the logical link is established and terminated between two different nodes. It also has a traffic control frame that commands the nod of transmission to stop when there are no frame buffers available. The layer is also characterized by frame sequencing that sees to it that it transmits or receives the frames sequentially. The layer’s other characteristics are it has frame acknowledgment, frame delimiting, error checking capabilities, and a medium that allows for management access (Rhee, 2003).
The network layer helps in control subnet operations throbbing decisions about which path a data should .move to the conditions of the network, service priority, and other related factors.