Suggested answers November 2018 - ITSM

November 2018 - Information technology and strategic management

1(a) Disadvantages of decision trees:

1. They are unstable, meaning that a small change in the data can lead to a large change in the structure of the optimal decision tree.
2. They are often relatively inaccurate. Many other predictors perform better with similar data. This can be remedied by replacing a single decision tree with a random forest of decision trees, but a random forest is not as easy to interpret as a single decision tree.
3. For data including categorical variables with different number of levels, information gain in decision trees is biased in favor of those attributes with more levels.
4. Calculations can get very complex, particularly if many values are uncertain and/or if many outcomes are linked.

1(b)

• Resilience refers to the ability of a network to recoer from any kind of error like connection failure, loss of data etc.
• Contention refers to the situation that arises when there is a conflict for some common resource in a network. For example, network contention could arise when two or more computer systems try to communicate at the same time.

1(c)

Authentication means that the receiver is sure of the sender's identity and that an imposter has not sent the message

Integrity means that the data must arrive at the receiver exactly as it was sent, there must not be any changes during the transmission either accidental or malicious

1(d)

CRM - Customer relationship management - Customer-relationship management (CRM) is an approach to manage a company's interaction with current and potential customers. It uses data analysis about customers' history with a company to improve business relationships with customers, specifically focusing on customer retention and ultimately driving sales growth

SRM - Supplier relationship management - Supplier relationship management (SRM) is the systematic approach of assessing suppliers' contributions and influence on success, determining tactics to maximize suppliers' performance and developing the strategic approach for executing on these determinations. It helps to create positive buyer-supplier relationships and determines which activities to engage in with each supplier. Supplier relationship management is used by supply chain professionals involved in areas such as procurement, project management and operations where these professionals regularly deal with suppliers. SRM includes both business practices and software.

1(e) 

SaaS - It includes a complete software offereing on the cloud. Users can access a software application hosted by the cloud vendor on pay per use basis.

PaaS - It provides clients with access to the basic operating software and optional services to develop and use software application without need to buy and manage the underlying computing insfrastructure. Google App Engine

2

Answer on YouTube - https://www.youtube.com/watch?v=U14jaxI2gvo

3(a)

3(b)

(i) Mesh Network: 

In this structure, there is random connection of nodes using communication links. A mesh network may be fully connected (as shown in Fig 3.7.3) or connected with only partial links. In fully interconnected topology, each node is connected by a dedicated point to point link to every node. The reliability is very high as there are always alternate paths available if direct link between two nodes is down or dysfunctional. Fully connected networks are not very common because of the high cost. Only military installations, which need high degree of redundancy, may have such networks, that too with a small number of nodes

Advantages of mesh network are as under:

• Yields the greatest amount of redundancy in the event that if one of the nodes fails, the network traffic can be redirected to another node.
• Network problems are easier to diagnose. 

(ii) Ring Network: A ring network is much like a bus network, except the length of wire, cable, or optical fiber connects to form a loop. 

The characteristics of a ring network are:

• Local computer processors are tied together sequentially in a ring with each device being connected to two other devices.
• A ring network has a decentralized approach.
• When one computer needs data from another computer, the data is passed along the ring.
• Considered more reliable and less costly than star networks because if one computer fails, the other computers in the ring can continue to process their own work and communicate with each other. 

Advantages of ring network include the following:

• Ring networks do not require a central computer to control activity nor does it need a file server.
• Each computer connected to the network can communicate directly with the other computers in the network by using the common communication channel, and each computer does its own independent applications processing.
• The ring network is not as susceptible to breakdowns as the star network, because when one computer in the ring fails, it does not necessarily affect the processing or communications capabilities of the other computers in the ring.
• Ring networks offer high performance for a small number of workstations or for larger networks where each station has a similar workload.
• Ring networks can span longer distances than other types of networks.
• Ring networks are easily extendable. 

(iii) Star Network: The star network, a popular network configuration, involves a central unit that has a number of terminals tied into it.

The characteristics of a star network are:

• It ties end user computers to a central computer.
• The central unit in the star network acts as the traffic controller among all the other computers tied to it. 
• The central computer is usually a mainframe (host), which acts as the file server.

A star network is well suited to companies with one large data processing facility shared by a number of smaller departments. Many star networks take the form of hierarchical networks with a centralized approach.

Advantages of the star network include the following:

• Several users can use the central unit at the same time.
• It is easy to add new nodes and remove existing nodes.
• A node failure does not bring down the entire network.
• It is easier to diagnose network problems through a central hub.

4 (a)

Approaches to Access Control There are two major approaches to establish access controls, which are given as under:

1. Role-based Access Control (RBAC): RBAC largely eliminates discretion when providing access to objects. Instead, administrators or automated systems place subjects into roles. Subjects receive only the rights and permissions assigned to those roles. When an employee changes jobs, all previous access is removed, and the rights and permissions of the new role are assigned.
2. Rules-based Access Control (RAC): RAC differs from RBAC methods because it is largely context-based. RBAC, for example, enforces static constraints based on a user’s role. RAC, however, also takes into account the data affected, the identity attempting to perform a task, and other triggers governed by business rules. A manager, for example, has the ability to approve his/her employees’ hours worked. However, when s/he attempts to approve his/her own hours, a rule built into the application compares the employee record and the user, sees they are the same, and temporarily removes approval privilege. Note that this is dynamic and occurs at the time a transaction is attempted. This also sometimes called dynamic RBAC. 

4(b) 

5(a) 

Some benefits of pursuing such automation include the following:

1. Reducing the Impact of Human Error: BPA removes human participation in the process, which is the source of many errors.
2. Transforming Data into Information: BPA can, apart from collecting and storing data also analyze data and make it available in a form that is useful for decision-making.
3. Improving performance and process effectiveness: In many cases, tasks that must be done manually are the bottleneck in the process. Automating those manual tasks speeds up the effective throughput of the application.
4. Making users more efficient and effective: People can focus their energies on the tasks they do best, allowing the computers to handle those that machines are best suited for.
5. Making the business more responsive: Enterprises can easily automate new applications and processes as they are introduced that provide greater control over business and IT processes.
6. Improving Collaboration and Information Sharing: Business processes designed through a collaborative interface mean IT can integrate its processes with the business side logic that drives day-to-day operations.
7. Cost Saving: Automation leads to saving in time and labor costs through higher efficiency and better management of the people involved;
8. To remain competitive: To provide the level of products and services as offered by competition. 
9. Fast service to customers: Automation shortens cycle times in the execution of processes through improved and refined business workflows and help enterprises to serve their customers faster and better. 

5(b)

Adequate controls should be enforced through the front end application system also, to have consistency in the control process.

Some of them are as follows:

1. Run-to-Run Totals: These help in verifying data that is subject to process through different stages. A specific record (probably the last record) can be used to maintain the control total.
2. Reasonableness Verification: Two or more fields can be compared and cross verified to ensure their correctness.
3. Edit Checks: Edit checks similar to the data validation controls can also be used at the processing stage to verify accuracy and completeness of data.
4. Field Initialization: Data overflow can occur, if records are constantly added to a table or if fields are added to a record without initializing it, i.e., setting all values to zero before inserting the field or record.
5. Exception Reports: Exception reports are generated to identify errors in data processed.
6. Existence/Recovery Controls: The check-point/restart logs, facility is a short-term backup and recovery control that enables a system to be recovered if failure is temporary and localized. 

6(a)

Mobile Computing:

Mobile Computing, is the use of portable computing devices (such as laptop and handheld computers) in conjunction with mobile communications technologies to enable users to access the Internet and data on their home or work computers from anywhere in the world. It is a human–computer interaction by which a computer is expected to be transported during normal usage. Mobile computing involves Mobile Communication, Mobile Hardware and Mobile Software; these are discussed as follows:

1. Mobile Communication: Mobile Communication refers to the infrastructure put in place to ensure that seamless and reliable communication goes on. These would include devices such as Protocols, Services, Bandwidth and Portals necessary to facilitate and support the stated services. The data format is also defined at this stage. The signals are carried over the air to intended devices that are capable of receiving and sending similar kinds of signals. It will incorporate all aspects of wireless communication.
2. Mobile Hardware: Mobile Hardware includes mobile devices or device components that receive or access the service of mobility. They would range from Portable laptops, Smart phones, Tablet PC’s to Personal Digital Assistants. These devices will have receptors that are capable of sensing and receiving signals. These devices are configured to operate in full- duplex, whereby they are capable of sending and receiving signals at the same time.
3. Mobile Software: Mobile Software is the actual program that runs on the mobile hardware. It deals with the characteristics and requirements of mobile applications. This is the engine of that mobile device. In other terms, it is the operating system of that appliance. It is the essential component that makes the mobile device operates.  

6(b)

Major advantages of DBMS are given as follows:

1. Permitting data sharing: One of the principle advantages of a DBMS is that the same information can be made available to different users.
2. Minimizing Data Redundancy: In a DBMS duplication of information or redundancy is, if not eliminated, carefully controlled or reduced i.e. there is no need to repeat the same data over and over again. Minimizing redundancy can therefore significantly reduce the cost of storing information on hard drives and other storage devices.
3. Integrity can be maintained: Data integrity is maintained by having accurate, consistent, and up-to-date data. Updates and changes to the data only have to be made in one place in DBMS ensuring Integrity. The chances of making a mistake increase if the same data needs to be changed at several different places than making the change in one place.
4. Program and file consistency: Using a DBMS, file formats and programs are standardized. This makes the data files easier to maintain because the same rules and guidelines apply across all types of data. The level of consistency across files and programs also makes it easier to manage data when multiple programmers are involved.
5. User-friendly: DBMS makes the data access and manipulation easier for the user. DBMS also reduce the reliance of users on computer experts to meet their data needs.
6. Improved security: DBMSs allow multiple users to access the same data resources which could lead to risk to an enterprise if not controlled. Security constraints can be defined i.e. Rules can be built to give access to sensitive data

Disadvantages of a DBMS are given as under: 

1. Cost: Implementing a DBMS system can be expensive and time-consuming, especially in large enterprises. Training requirements alone can be quite costly.
2. Security: Even with safeguards in place, it may be possible for some unauthorized users to access the database. If one gets access to database then it could be an all or nothing proposition.

7(a)

Top-Down Commitment, Bottom - Up Execution: In order for BPM to work, top management needs to commit to it and support the process-focused management approach it requires. Undoubtedly, organizations adopting BPM will go through difficulties and oppositions. Without top management commitment, BPM will likely to disappear because of internal organizational resistance. Executing process improvement should use a bottom-up approach. The benefit of a bottom-up approach is it encounters less resistance from the employees most directly affected by the change.

7(b)

Memory Management: Memory Management features of Operating System allow controlling how memory is accessed and maximize available memory & storage. Operating systems also provides Virtual Memory by carving an area of hard disk to supplement the functional memory capacity of RAM. In this way it augments memory by creating a virtual RAM. 

7(c)

The risks associated with e-Commerce are multi-faceted. Given below is a sample listing of risks of e-Commerce:

• Problem of anonymity: There is need to identify and authenticate users in the virtual global market where anyone can sell to or buy from anyone, anything from anywhere.
• Repudiation of contract: There is possibility that the electronic transaction in the form of contract, sale order or purchase by the trading partner or customer may be denied.
• Lack of authenticity of transactions: The electronic documents that are produced in the course of an e-Commerce transaction may not be authentic and reliable.
• Data Loss or theft or duplication: The data transmitted over the Internet may be lost, duplicated, tampered with or replayed.
• Attack from hackers: Web servers used for e-Commerce may be vulnerable to hackers.
• Denial of Service: Service to customers may be denied due to non-availability of system as it may be affected by viruses, e-mail bombs and floods.
• Non-recognition of electronic transactions: e-Commerce transactions, as electronic records and digital signatures may not be recognized as evidence in courts of law.
• Lack of audit trails: Audit trails in e-Commerce system may be lacking and the logs may be incomplete, too voluminous or easily tampered with Problem of piracy: Intellectual property may not be adequately protected when such property is transacted through e-Commerce 

7(d)

The electronic cheque can prove to be superior to the paper cheque in one significant aspect. As sender, we can protect ourselves against fraud by encoding our account number with the bank’s public key, thereby not revealing our account number to the merchant. As with the SET protocol, digital certificates can be used to authenticate the payer, the payer’s bank, and bank account.

7(e)

Resource Balancing: For applications that are grid-enabled, the grid can offer a resource balancing effect by scheduling grid jobs on machines with low utilization. This feature of grid computing handles occasional peak loads of activity in parts of a larger organization. An unexpected peak can be routed to relatively idle machines in the grid; and if the grid is already fully utilized, the lowest priority work being performed on the grid can be temporarily suspended or even cancelled and performed again later to make room for the higher priority work.