Network Management Chapter 123 review Homework
Chapter 1
1. Explain the term network management in one sentence.
Answer: Network management is a set of tools, action, method and procedures to enable the proper administration of a network.
2. We used a patient in intensive care as one analogy to explain network management. Can
you think of areas in network management that this analogy does not capture?
Answer: This analogy does not capture the setting up, mapping or in other words the provisioning of a network.
3. Can you think of other areas in which you would expect analogies to network management
to apply?
Answer: The management of the AirTrain that is the trains at JFK airport can be analogous. It is management for timeliness, being subject to a fine in not. Maintenance is a factor, planning comes into play based on the different seasons and weather conditions.
4. Give two examples of how network management can help an enterprise IT department save
money.
Answer: One making routine tasks automatic can save time and in the long run money. Also, localize trouble shooting can save time and money, as the work load does not need to be outsourced.
.
5. Give two examples of how network management can help a service provider increase
revenue.
Answer: For example, at Verizon, the company is fine by the BTU if it cannot provide reliable service. Therefore proper management of the network reduces fines and increases revenue. Another, capability is that a properly managed network has a faster turn up time than one that is not, hence new services can be added faster and more reliable, thus increasing revenue.
6. A famous requirement for availability is “five nines.” This refers to the requirement that a
device or a service must be available 99.999 percent of the time. Assume that you have a
device with hardware availability of 99.9995 percent. Now assume that an operational error
is made that causes the device to go offline for 5 minutes until the error is corrected.
Calculated over a period of a month, how much has the operational error just caused
availability to drop?
Answer: Availability dropped from five nines to three nines. 30 day in a month, 24 hours in a day, 60 minutes in an hour and 60 seconds in a minute. 30*24*60*60 = 2,592,000
seconds in a month for a 100% system. 99.9995% , means 2592,000* 0.999995= 2591,987 seconds without error. Minus 5 minutes, that is 5*60=300 seconds, would give 2591,987-300 = 2591,687 seconds, (2591,687/2592,000) * 100 = 99.9879% hence yielding three nines.
7. How does the perspective under which network management is approached often differ for an
enterprise IT department compared to a service provider?
Answer: A service provider exist to provide a service which yields a profit, while the enterprise IT department exist to provide cost effective services not to yield a cost but reliable production and therefore will use off the shelf products to accomplish its job, while a service provider will customize its products for a specific job to yield its profits.
8. Name at least two factors that can be important to the business success of a third-party
management application vendor that potentially has to compete with a network management
offering of a network equipment vendor.
Answer: Factors that could contribute to a third party’s success could be the ability to be used on a variety of platforms/vendors hence it should be cross platform application. It should also be expandable to new platforms/ vendors and also should not be limited to any specific equipment or service type but should take into consideration, network propagation as a whole
9. What does the term swivel-chair syndrome refer to, and why is this undesired?
Answer: It alludes to the fact that networks management operators manage multiply equipment/terminals at one time, they sit on a swivel chair and orient between these different terminals to perform their duties. This concept is undesired in that it is costly to have so many different terminals, when compared to getting an all-in-one solution, which is more costly, but over time it cost less to own. The swivel-chair syndrome can also cause health issues but refers to the problem of a lack of integration between management applications,
10. Name two or more reasons for network management applications to be approached as
distributed systems.
Answer: Management applications are distributed by nature as it covers multiple communications systems (management systems and network equipment). Being as such, it is expandable, addressing scalability. It provides for follow-the-sun operations across geographically diverse regions.
Chapter 2
1. Is running a network only a matter of network management technology, or are there other
considerations?
Answer: No, it is also considerate of human factors and a management hierarchy, which are planning, implementation, maintenance and protocols
2. What does Pat’s employer use to track the resolution of problems in the network?
Answer: Trouble tickets, which managed through a trouble ticket system. Trouble tickets contain all the information pertinent to the problem and the steps taken to resolve the problem.
3. How does the integration of the work order system with the trouble ticket system make Pat’s
job easier?
Answer: It alleviates redundancy or the repetition of entering repeated information, thus reducing possible errors. The tacking system notifies and logs each step of the trouble event including the work order that is issued to correct the problem.
4. Which network provider do you think will be more vulnerable to human failures by
operations personnel, Pat’s or Chris’s?
Answer: Chris’s. Pat’s well-defined procedures allow for tracking and it is automated thus reducing human errors. Chris’s work output is solely dependent on him; therefore if he does not do his job then the network suffers.
5. Which of the following can be used as management tools? A. alarm management system, B.
spreadsheet, C. pencil and piece of paper, D. all of them.
Answer: D is clearly the correct answer. Pencil and paper can be used to write down troubles or instantaneous values, spreadsheet can be used to look at trend s in the management systems and alarms give notification of troubles in the network system.
6. In how many different places does Chris need to maintain the same phone number, and why
could this be an issue?
Answer: In four places, namely; voice-mail system, IP PBX, company directory and the phone number inventory. Chris’s processes are not streamlined, and an integrated or all-in-one system could help productivity a lot.
7. When Chris is worried about compromised security of his company’s network, does the threat
come from outside attackers or from within the network?
Answer: As stated numerous times in class, the number one threat comes from within the network. When managing the security of a network, all aspects of security should be addressed; both the internal and external security threats. Disgruntled employees can devastate a network system more severely than an outside threat.
8. Connectivity between different company sites is provided by an outside MSP. Why is Chris
nevertheless concerned with monitoring traffic statistics across these outside connections?
Answer: Chris still needs to know that he is getting the product/security that he paid for.
9. When Sandy wants to implement a security policy for the Internet Data Center, at what
different levels does she take security into account?
Answer: Ashe takes into account the network itself firewalls, VLANs, ports, security for data usage, and also the user apps.
10. Why is Sandy interested in “old” performance data and traffic statistics, even though she is
not monitoring actual network operations?
Answer: She needs to know how the network has performed in the past, so she can use this information for improvement/planning or even downgrades as needs of business continues.
Chapter 3
1. Name the two contexts in which the term agent is used in network management.
Answer: a) The management agent which is the software component that provides a pictorial view of all the managed components in the network.
b) The agent role, which function or propose of the network element being managed in the managing system itself
.
2. Compare the manager/agent and client/server paradigms. What are the commonalities, and
what are the differences?
Answer: In both are reflective of each other, and depends on what level of a management system they occur, as they at times do similar duties, both send and receives request. Both can affect other elements in the system. They differ in that manager/agent manages many agents even client/servers, while servers manage many clients
3. The chapter stated that a network element can contain more than one management agent and
that a management agent can contain embedded management intelligence. Taking these
statements literally can lead to the conclusion that the same management intelligence might
have to be implemented redundantly in a network element, once for each management agent.
Clearly, this would be a wasteful approach. What would be an appropriate refinement of the
model of a management agent?
Answer: Shared management intelligence between different management agents would make the same information accessible across several management interfaces. MIBs comes to mind and could be made accessible in a way that is not burdensome to the network.
4. Explain the term MIB—what does the acronym stand for, what is it, and who provides it?
Answer: MIB stands for Management Information Base. It contain information of a
network element for management purposes. It is provided by a system in an agent role.
5. Name one difference between a MIB and a database.
Answer: The MIB represents active or current view of real resources within a network, while a database is passive or static which is maintained outside a network.
6. Tell whether the following statement is true: “If a network is required to have availability of
99.999 percent, its management systems need to also be 99.999 percent available.” Why or
why not? Please elaborate. For extra points, factor in the influence of the type of application
that the management system is used for.
Answer: The need of a network to provide five nines functionality should be independent of the networks management, however the management system helps to achieve and maintain a managed system. A highly planned out and reliable systems does not need its management system to be up and running 99.999% all the time, but a system that is used to provide billing for data or bandwidth usage would need on as not having one could lead to loss or revenue.
7. Management traffic is different from other communication traffic, in that the NE itself is a
destination and originator of traffic. However, it is not the only type of traffic for which this
is true. Name an example of other network traffic that the NE does not just switch or route,
but actively participates in.
Answer: Routing protocols used in the control and traffic signaling.
8. What could be the most important reason for using a dedicated management network instead
of a shared one?
Answer: Of most importance is reliability. In cases as used for banking dedicated management is needed to determine errors accurately and timely. A undedicated network can have conflict of traffic from the production and management elements.
9. Which other term do service providers use to refer to management systems?
Answer: Operational support systems (OSS).
10. Would you expect a management system to provision services to be located at a NOC or at a
Central Office? Why?
Answer: At a NOC. The NOC is the Network Operations Center from which the network is
managed in manned, has a detailed map or database of all the network elements are located there and all the management capabilities of the network, while at a CO or central office, only the physical termination and routing takes place and is sometimes unmanned or has a rover.
