ABSTRACT
The open system interconnections (OSI) model allows data communications technology developers, as well as standards developers, to talk about the interconnection of two networks or computers in common terms without dealing in proprietary vendor jargon. Ultimately, the OSI model provides a structured methodology for determining what hardware and software technologies will be required in the physical network design in order to meet the requirements of the logical network design. Layer 2 of the OSI model, the data-link layer, describes hardware that enables data transmission. Because of the complexities of linking multiple topologies, cabling systems, and operating systems, the following failure modes may be experienced: The data link layer usually includes some type of routing hardware, including one or more of the following: Ethernet is the most common data link layer protocol. The transport layer has the ability to save transmissions that were route in the case of a system crash.
