print barcode labels in c# Lesson 1 in VB.NET

Paint ECC200 in VB.NET Lesson 1

At the low end, workstations require little more than the basic components needed to run the operating system. If you want the users to be limited to a specific workstation configuration, you might even want to omit the CD-ROM and floppy disk drives, so they cannot install their own applications or boot the computer with another operating system. Workstations that have to perform resource-intensive tasks can start to look a lot like servers in terms of processor speed, amount of memory, and disk capacity, but they don t typically have the same availability requirements as a server. The basic function of a desktop workstation on a network is to access server applications or files stored on servers so that the user can work with the data. Here again, the capabilities of the workstation are defined by the applications it runs. In some cases, the applications your workstations use are dictated by the applications you selected for your servers. For example, you might have to run a specific client program to connect to a server application.

Portable workstations can also perform a number of different roles, depending on the needs of the users. In most cases, a portable workstation refers to a notebook com puter, but personal digital assistants (PDAs) and other handhelds are becoming viable options for the traveling user. In some cases, portable computers must be capable of supporting all the functions of a desktop workstation, while other users prefer to sac rifice functionality for a smaller size and less weight.

Creating hardware specifications before you begin evaluating computers for your network enables you to decide which components a computer needs to fulfill a particular role. Administering a large fleet of computers is easiest when you define your comput ers roles and standardize the hardware and software needed for each role. This way, support personnel know what to expect when they troubleshoot a problem.

When you create the hardware specification for a server, you must consider the requirements and capabilities of the applications that the server will run. Computers that are marketed as servers typically have more robust power supplies than normal PCs. A server might also have integrated components not usually found in a worksta tion, such as network interface adapters, SCSI host adapters, and drive arrays.

nents you select are on the operating system manufacturer s list of tested and approved prod ucts. For the Microsoft Windows operating systems, check the Hardware Compatibility List for Windows 2000 and earlier operating systems and the Windows Server Catalog for Microsoft Windows XP and later operating systems for system compatibility.

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The amount of random access memory (RAM) and the speed and number of proces sors should always be part of a hardware specification for a server. Furthermore, in addition to the components that you want in the server when you purchase it, you should also specify the server s maximum capacity for these components, to account for future upgrades. For example, if you intend to purchase a server with one gigabyte of RAM, make sure that the computer can support at least two gigabytes (or more), so that you can install additional memory later, if necessary. You might also purchase a server that supports multiple processors, even if you are only going to use one right now. This way, you can always scale up the server s per formance by installing additional processors. In the same way, you should plan for future as well as current server disk capacity. For example, select disk arrays with slots for additional disks, or computer cases with enough internal bays for expansion. In addition to the performance levels your organization and your applications require, you should also consider your requirements for fault tolerance and availability, because these elements might affect your hardware specifications. Disk arrays that use hot plugging and redundant array of independent disks (RAID), redundant power supplies, shared storage solutions, tape backup drives, and server clusters all can be sub stantial additions to your server configurations.