Chapter 2


What is ANSI, and what does it do?


Answer: ANSI is the acronym for the American National Standards Institute and is a U.S. governmental body responsible for approving U.S. standards in several categories, including computers and communications.


What is the ITU-T, and what does it do?


Answer: The ITU-T is the telecommunications standardization sector of the ITU (International Telecommunication Union) and is responsible for technical recommendations about telephone and data communications systems telecommunications carriers.


What is the IEEE, and what does it do?


Answer: The IEEE is the Institute of Electrical and Electronics Engineers and is the leading technical authority in several technology fields, such as computer engineering and electronics.


What does OSI stand for, and what is the OSI model?


Answer: OSI stands for Open System Interconnection. The OSI model is a model of network architecture and of the protocol suites across the network architecture. The OSI model was developed as a framework for international standards in various and diverse computer network architectures to be developed and implemented.


Describe and name the layers in the OSI model.


Answer: There are seven (7) layers in the OSI model: (7) application, (6) presentation, (5) session, (4) transport, (3) network, (2) data link, and (1) physical.


What are some advantages of a layered model approach to networking?


Answer: Whether it is the OSI model layers or the Hierarchical Design Model layers, the layered approach provides the same advantages: the compartmentalization of network functions. This compartmentalization enables vendors to develop and produce a specific product set, such as network hardware (routers, switches) or software (computer or network operating system). This same compartmentalization provides the network administrator a step-by-step approach to troubleshooting a network fault, and to isolating the failure from the rest of the network, such as implementing a failover path or replacing the hardware


What is the network standard for 10-Mbps Ethernet? 100-Mbps Ethernet? 1000-Mbps/Gigabit Ethernet? 10Gigabit Ethernet?


Answer: 10-Mbps Ethernet?IEEE 802.3

100-Mbps Ethernet?IEEE 802.3u

1-Gbps 1000-Mbps?IEEE 802.3z

10,000-Mbps/10-Gbps Ethernet?IEEE 802.3ae


What is encapsulation, and how does it work (in reference to the OSI model)?


Answer: Encapsulation is the process by which each layer of the OSI model wraps protocol information around the information received from the layer above. Each layer of the OSI model performs a specific function, adding that layer's information; based on this information, the receiving side knows what to do upon receipt of the data.