In the 1980s, when we wrote the first edition of this book, there were many, many more protocols in common use at the data link, network, and transport layers than there are today. Why do you think the number of commonly used protocols at these layers has declined? Do you think this trend will continue? What are the implications for those who design and operate networks?
> Compare and contrast two-tier, three-tier, and n-tier client–server architectures. What are the technical differences, and what advantages and disadvantages does each offer?
> What are the three ways of reducing errors and the types of noise they affect?
> How do amplifiers differ from repeaters?
> Describe four types of noise. Which is likely to pose the greatest problem to network managers?
> What does the data link layer do?
> Briefly describe three important coding schemes.
> What is coding?
> Explain why most telephone company circuits are now digital.
> Clearly explain the differences among analog data, analog transmission, digital data, and digital transmission.
> How do analog data differ from digital data?
> Describe four types of wireless media.
> Which is less expensive: host-based networks or client–server networks? Explain.
> Describe three types of guided media.
> Why is data compression so useful?
> What is oversampling?
> What factors affect transmission speed?
> What is 64-QAM?
> What is quadrature amplitude modulation (QAM)?
> What is a modem?
> Describe the three types of data flows.
> Is the bit rate the same as the symbol rate? Explain.
> Describe how data could be transmitted using a combination of modulation techniques.
> Suppose your organization was contemplating switching from a host-based architecture to client–server. What problems would you foresee?
> Describe how data could be transmitted using phase modulation.
> Describe how data could be transmitted using frequency modulation.
> Describe how data could be transmitted using amplitude modulation.
> What is bandwidth? What is the bandwidth in a traditional North American telephone circuit?
> What are three important characteristics of a sound wave?
> How does bipolar signaling differ from unipolar signaling? Why is Manchester encoding more popular than either?
> What feature distinguishes serial mode from parallel mode?
> How are data transmitted in parallel?
> How does a multipoint circuit differ from a point-to-point circuit?
> What is VoIP?
> What is middleware, and what does it do?
> What is the symbol rate of a digital circuit providing 100 Mbps if it uses bipolar NRz signaling?
> What is the capacity of a digital circuit with a symbol rate of 10 MHz using Manchester encoding?
> What is the maximum data rate of an analog circuit with a 10 MHz bandwidth using 64-QAM and V.44?
> What is the maximum capacity of an analog circuit with a bandwidth of 4,000 Hz using QAM?
> Some experts argue that modems may soon become obsolete. Do you agree? Why or why not?
> What is a client?
> What is a circuit?
> How do LANs differ from WAN sand BNs?
> If you were buying a multiplexer, would you choose TDM or FDM? Why?
> Discuss three important applications of data communications networks in business and personal use.
> How can data communications networks affect businesses?
> What is the Internet of Things (IoT)? What are the benefits and risks?
> What are three cyber security issues?
> How many bits (not bytes) are there in a 10-page text document?
> The number of standardized protocols in use at the application layer has significantly increased since the 1980s. Why? Do you think this trend will continue? What are the implications for those who design and operate networks?
> Why has the Internet model replaced the OSI model?
> Discuss three trends in communications and networking.
> What is the purpose of a data communications standard?
> What is the function of inverse multiplexing (IMUX)?
> Describe two important data communications standards-making bodies. How do they differ?
> How are Internet standards developed?
> Describe the three stages of standardization.
> Explain how a message is transmitted from one computer to another using layers.
> How many bits (not bytes) are there in a 10 page text document? Hint: There are approximately 350 words on a double-spaced page.
> Describe the seven layers in the OSI network model and what they do.
> Why are network layers important?
> What is a server?
> What do trouble tickets report?
> What does a help desk do?
> Of the different types of multiplexing, what distinguishes: a. Frequency division multiplexing (FDM)? b. Time division multiplexing (TDM)? c. Statistical time division multiplexing (STDM)? d. Wavelength division multiplexing (WDM)?
> What is performance and fault management?
> What is desktop management, and why is it important?
> People tend to think of software when documentation is mentioned. What is documentation in a network situation?
> Describe what configuration management encompasses.
> Why is combining voice and data a major organizational challenge?
> Many organizations do not have a formal trouble reporting system. Why do you think this is the case?
> How does network cost of ownership (aka real TCO) differ from total cost of ownership? Which is the most useful measure of network costs from the point of view of the network manager? Why?
> How does content caching differ from content delivery?
> What is capacity management?
> What is policy-based management?
> How does DSL (digital subscriber line) work?
> What is server virtualization?
> How does a load balancer work?
> Compare and contrast device management software, system management software, and application management software.
> What is firefighting?
> What is SNMP and RMON?
> What do network management software systems do and why are they important?
> How can network costs be reduced?
> Why is the TCO so high?
> What is TCO?
> What are the primary functions of end user support?
> What is the purpose of multiplexing?
> What are the advantages and disadvantages of host-based networks versus client–server networks?
> What is problem escalation?
> How is network availability calculated?
> What is an SLA?
> Several important statistics related to network uptime and downtime are discussed in this chapter. What are they, and why are they important?
> What skill does a network manager need?
> Why is it important to identify improvements that are needed to mitigate risks?
> What are the possible risk control strategies? How do we pick which one to use?
> What is the purpose of the risk score, and how is it calculated?
> Explain the purpose of threat scenarios. What are the steps in preparing threat scenarios?
> Although it is important to protect all servers, some servers are more important than others. What server(s) are the most important to protect and why?
> What is the term used to describe the placing of two or more signals on a single circuit?
> What is one of the major risks of downloading unauthorized copies of music files from the Internet (aside from the risk of fines and lawsuits)?
> Some experts argue that CERT’s posting of security holes on its website causes more security break-ins than it prevents and should be stopped. What are the pros and cons on both sides of this argument? Do you think CERT should continue to post security h
