Note the advantages of a SAN.

Match the items in Table A with the statements in Table B.

Table A

a NAS

b Fibre Channel

c SAN

d Mirror

e Server farm

f Disk array

Table B

i Storage area network

ii Write copies of data to two disks at the same time

iii A large collection of computers that work together to provide services on a network

iv Network attached storage

v A set of interconnected disks

vi A type of high speed interconnection

3. Using information from the text, mark the following as True or False:

a In the traditional storage model, it is always possible for every user to access each storage device,

b Hanging storage devices off servers is the most basic way of expanding storage capacity,

c The distance limitation of SCSI affects the direct connection of storage devices to a server,

d A SAN is not usually connected to a LAN.

e All devices can be centrally managed in a SAN.

f Fast Ethernet is becoming the most popular type of interconnection for SANs.

Text 14

I. Find the answers to these questions in the following text.

1. What advantages of using object-oriented programming are mentioned in the text?

2. What are the three key features of OOP?

3. What multimedia data types are referred to in the text?

4. List the different types of triangle mentioned in the text.

5. What feature avoids the problem of deciding how each separate type of data is integrated and synchronized into a working whole?

6. What specific type of rectangle is named in the text?

7. What common properties of a rectangle are mentioned in the text?

8. What features are made quicker by code reusability?

OBJECT-ORIENTED PROGRAMMING

One of the principal motivations for using OOP is to handle multimedia applications in which such diverse data types as sound and video can be packaged together into executable modules. Another is writing program code that's more intuitive and reusable; in other words, code that shortens program-development time.

Perhaps the key feature of OOP is encapsulation - bundling data and program instructions into modules called 'objects'. Here's an example of how objects work. An icon on a display screen might be called 'Triangles'. When the user selects the Triangles icon - which is an object composed of the properties of triangles (see fig. below) and other data and instructions - a menu might appear on the screen offering several choices. The choices may be (1) create a new triangle and (2) fetch a triangle already in storage. The menu, too, is an object, as are the choices on it. Each time a user selects an object, instructions inside the object are executed with whatever properties or data the object holds, to get to the next step. For instance, when the user wants to create a triangle, the application might execute a set of instructions that displays several types of triangles - right, equilateral, isosceles, and so on. Many industry observers feel that the encapsulation feature of OOP is the natural tool for complex applications in which speech and moving images are integrated with text and graphics. With moving images and voice built into the objects themselves, program developers avoid the sticky problem of deciding how each separate type of data is to be integrated and synchronized into a working whole.

A second key feature of OOP is inheritance. This allows OOP developers to define one class of objects, say 'Rectangles', and a specific instance of this class, say 'Squares' (a rectangle with equal sides). Thus, all properties of rectangles - 'Has 4 sides' and 'Contains 4 right angles' arc the two shown here - are automatically inherited by Squares. Inheritance is a useful property in rapidly processing business data. For instance, consider a business that has a class called 'Employees at the Dearborn Plant' and a specific instance of this class, 'Welders'. If employees at the Dearborn plant are eligible for a specific benefits package, welders automatically qualify for the package. If a welder named John Smith is later relocated from Dearborn to Birmingham, Alabama, where a different benefits package is available, revision is simple. An icon representing John Smith - such as John Smith's face - can be selected on the screen and dragged with a mouse to an icon representing the Birmingham plant. He then automatically 'inherits* the Birmingham benefit package.

A third principle behind OOP is polymorphism.

This means that different objects can receive the same instructions but deal with them in different ways. For instance, consider again the triangles example. If the user right clicks the mouse on 'Right triangle', a voice clip might explain the properties of right triangles. However, if the mouse is right clicked on 'Equilateral triangle* the voice instead explains properties of equilateral triangles.

The combination of encapsulation, inheritance and polymorphism leads to code reusability. 'Reusable code' means that new programs can easily be copied and pasted together from old programs. All one has to do is access a library of objects and stitch them into a working whole.

This eliminates the need to write code from scratch and then debug it. Code reusability makes both program development and program maintenance faster.

II. Re-read the text to find the answers to these questions.

1 Match the terms in Table A with the statements in Table B.

Table A

a. OOP e. Square

b. Encapsulation f. Polymorphism

c. Object g. Library

d. Menu

Table В

I. An OOP property that allows data and program instructions to be bundled into an object

II. A list of choices

III. An OOP property that enables different objects to deal with the same instruction in different ways

IV. A reusable collection of objects

V. A module containing data and program instructions

VI. Object-Oriented Programming

VII. A rectangle with equal sides

2 Complete the following text using words from the reading text:

Encapsulation,……………. and polymorphism are key features of……………. programming.

Encapsulation allows data and program instructions to be bundled together in…………….. called objects. Inheritance means that specific……………….. of a class of objects…………………. the properties of the class of objects. Polymorphism means that instructions are treated differently by different……………………..The combination of these ………………features of OOP means that program code is reusable. This speeds up………………….and………………..of programs.

Text 15

I. Find the answers to these questions in the following text.

1 What advice is given for someone who is stuck in a computing support job?

2 What questions should you ask yourself if you are thinking of getting extra training?

3 What computer program is mentioned in the text?

4 Name two ways of studying that are mentioned in the text.

5 What two factors will be affected by your level of experience?

6 Why is it important to become used to answering exam questions?

7 What factors help you decide whether the course will be suitable or cost effective?

8 What happens if you don't upgrade your certification?

Becoming certified

Suppose you're a support engineer. You're stuck in a job you don't like and you want to make a change. One way of making that change is to improve your marketability to potential employers by upgrading your skill-set. If you're going to train yourself up however, whose training should you undertake? If you need certificates, whose certificates should they be? Even if you get those certificates, how certain can you be that your salary will rise as a result? One solution is the range of certifications on offer from Microsoft.

Microsoft offers a large array of certification programmes aimed at anyone from the user of a single program such as Microsoft Word, to someone who wants to become a certified support engineer. There are a myriad of certificates to study for too. If you're the proud holder of any of those qualifications, then you're entitled to call yourself a Microsoft Certified Professional (MCP).

Once you've decided which track you want to take, you should consider just how qualified you already are in terms of experience and knowledge. Will you need to go and take some courses with a training company, or are you the type who can make good use of self-study materials? How much time do you genuinely have to devote towards this? Will your employer pay for your course? Will it grant you leave to go and do the course - assuming you can find one - on either a full-time or part-time basis?

The key question here is experience. This will not only influence the amount of work you'll have to do to get up to speed for the exams, it could also mean the difference between passing or failing the exam.

While you're busy learning all you need to know for your certification, the practice exams are an absolute godsend. They show you the type of questions you'll encounter, and they familiarize you with the structure of the exam. This is essential if you want to pass: the exams have time limits, and you need to get used to answering the requisite number of questions within the allotted time. It's as simple as that. If you decide a training course will help you out, don't let the title of a course alone convince you that it will be suitable or cost effective. Find out exactly what the course offers and whether there are pre-requisites for attendants. You should also find out what the training company is prepared to do if attendants don't have the minimum knowledge necessary to be on the course.

As exams are replaced by 'updated' ones, you need to upgrade your certification to stay current. Ultimately it's your responsibility to make sure you stay up to date. If you don't, you lose your certification until you take an update. As a support engineer, you get the satisfaction of knowing that you passed a tough test, and the happy knowledge that your network manager is sweating a bit over the fact that you could be head-hunted at any time.

QUALIFICATIONS