Chapter 16 2) What is meant by a primary station? A Secondary Station? 6) Briefl

Question

Chapter 16

2) What is meant by a primary station? A Secondary Station?

6) Briefly describe the poll/select line discipline

8) Briefly describe the sliding window method of flow control

9)What is the difference between character-and bit-oriented protocols?

Chapter 18

2) Describe the advantages of using LANs

3) What is the primary purpose of the IEEE project?

5) What is a Medium access method?

6) Explain Medium Access Control

7) List and Describe the two broad categories of medium access.

Chapter 19

1) What organization developed the Internet?

2) Briefly describe the functions of each layer of the OSI seven-layer protocol hierarchy.

3) Compare the layers of the OSI seven-layer protocol suite to the TCP/IP protocol suite.

4) Briefly describe the process of producing a request for comments (RFC) document.

17) What is the purpose of an IP address mask?

18) What are the default address mask for class A, B, and C IP addresses?

Explanation / Answer

CHAPTER 19

1.

In 1957, the Soviet Union launched the first satellite, Sputnik I, triggering US President Dwight Eisenhower to create the ARPA agency to regain the technological lead in the arms race. ARPA appointed J.C.R. Licklider to head the new IPTO organization with a mandate to further the research of the SAGEprogram and help protect the US against a space-based nuclear attack. Licklider evangelized within the IPTO about the potential benefits of a country-wide communications network, influencing his successors to hire Lawrence Roberts to implement his vision.

Roberts led development of the network, based on the new idea of packet switching invented by Paul Baran at RAND, and a few years later by Donald Davies at the UK National Physical Laboratory. A special computer called anInterface Message Processor was developed to realize the design, and theARPANET went live in early October, 1969. The first communications were between Leonard Kleinrock's research center at the University of California at Los Angeles, and Douglas Engelbart's center at the Stanford Research Institute.

The first networking protocol used on the ARPANET was the Network Control Program. In 1983, it was replaced with the TCP/IP protocol invented WbyRobert Kahn, Vinton Cerf, and others, which quickly became the most widely used network protocol in the world.

2.

1.Physical (Layer 1)

This layer conveys the bit stream - electrical impulse, light or radio signal -- through the network at the electrical and mechanical level. It provides the hardware means of sending and receiving data on a carrier, including defining cables, cards and physical aspects

2.Data Link (Layer 2)

At this layer, data packets are encoded and decoded into bits. It furnishes transmission protocol knowledge and management and handles errors in the physical layer, flow control and frame synchronization. The data link layer is divided into two sub layers: The Media Access Control (MAC) layer and the Logical Link Control (LLC) layer. The MAC sub layer controls how a computer on the network gains access to the data and permission to transmit it. The LLC layer controls frame synchronization, flow control and error checking.

3. Network (Layer 3)

This layer provides switching and routing technologies, creating logical paths, known as virtual circuits, for transmitting data from node to node. Routing and forwarding are functions of this layer, as well as addressing,internetworking, error handling, congestion control and packet sequencing.

4.Transport (Layer 4)

This layer provides transparent transfer of data between end systems, or hosts, and is responsible for end-to-end error recovery and flow control. It ensures complete data transfer.

5.Session (Layer 5)

This layer establishes, manages and terminates connections between applications. The session layer sets up, coordinates, and terminates conversations, exchanges, and dialogues between the applications at each end. It deals with session and connection coordination.

6.Presentation (Layer 6)

This layer provides independence from differences in data representation (e.g., encryption) by translating from application to network format, and vice versa. The presentation layer works to transform data into the form that the application layer can accept. This layer formats and encrypts data to be sent across a network, providing freedom from compatibility problems. It is sometimes called the syntax layer.

7.Application (Layer 7)

This layer supports application and end-user processes. Communication partners are identified, quality of service is identified, user authentication and privacy are considered, and any constraints on data syntax are identified. Everything at this layer is application-specific. This layer provides application services for file transfers,e-mail, and other network software services. Telnet and FTP are applications that exist entirely in the application level. Tiered application architectures are part of this layer.

3. OSI provides layer functioning and also defines functions of all layers. TCP/IP model is more based on protocols and protocols are not flexible with other layers.

In OSI, the transport layer guarentees delivery of packets. whereas In TCP/IP it doesnt.

OSI follows horizontal path. TCP/IP follows vertical approach.

OSI is general model. TCP/IP cannot be used in any other application.

OSI has 7 layers, TCP/IP has 4 layers

4.

The RFC Editor assigns each RFC a serial number. Once assigned a number and published, an RFC is never rescinded or modified; if the document requires amendments, the authors publish a revised document. Therefore, some RFCs supersede others; the superseded RFCs are said to be deprecated, obsolete, or obsoleted by the superseding RFC. Together, the serialized RFCs compose a continuous historical record of the evolution of Internet standards and practices.

The RFC production process differs from the standardization process of formal standards organizations such as ISO. Internet technology experts may submit an Internet Draftwithout support from an external institution. Standards-track RFCs are published with approval from the IETF, and are usually produced by experts participating in working groups, which first publish an Internet Draft. This approach facilitates initial rounds of peer review before documents mature into RFCs.

The RFC tradition of pragmatic, experience-driven, after-the-fact standards authorship accomplished by individuals or small working groups can have important advantages over the more formal, committee-driven process typical of ISO and national standards bodies.

Most RFCs use a common set of terms such as "MUST" and "NOT RECOMMENDED" (as defined by RFC 2119), Augmented Backus

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.