OPERATING SYSTEM

2009-07-16T03:25:00.000-07:00

4.Cooperating Processes

Independent process cannot affect or be affected by the execution of another process.
Cooperating process can affect or be affected by the execution of another process
Advantages of process cooperation

Information sharing
Computation speed-up
Modularity
Convenience

2009-07-16T03:21:00.000-07:00

5. Interprocess Communication (IPC)

Mechanism for processes to communicate and to synchronize their actions.

Message system – processes communicate with each other without resorting to shared variables.
IPC facility provides two operations:

send(message) –message size fixed or variable
receive(message)

3. If P and Q wish to communicate, they need to:

establish a communication link between them
exchange messages via send/receiven Implementation of communication link
physical (e.g., shared memory, hardware bus) considered later
logical (e.g., logical properties) now

2009-07-16T02:36:00.000-07:00

1.Concept on Process
An operating system executes a variety of programs:

Batch system – jobs
Time-shared systems – user programs or task

Textbook uses the terms job and process almost interchangeably.

Process – a program in execution; process execution must progress in sequential fashion.

A process includes:

program counter
stack

data section

Process State

As a process executes, it changes state

new: The process is being created.
running: Instructions are being executed.

waiting: The process is waiting for some event to occur

ready: The process is waiting to be assigned to a processor

terminated: The process has finished execution.

Process Control Block

Information associated with each process.

Process ID

Process staten Program counter

CPU registersn CPU scheduling information

Memory-management information

Accounting information

I/O status information

Threads

In computer science, a thread of execution results from a fork of a computer program into two or more concurrently running tasks. The implementation of threads and processes differs from one operating system to another, but in most cases, a thread is contained inside a process. Multiple threads can exist within the same process and share resources such as memory, while different processes do not share these resources.
On a single processor, multithreading generally occurs by time-division multiplexing (as in multitasking): the processor switches between different threads. This context switching generally happens frequently enough that the user perceives the threads or tasks as running at the same time. On a multiprocessor or multi-core system, the threads or tasks will generally run at the same time, with each processor or core running a particular thread or task. Support for threads in programming languages varies: a number of languages simply do not support having more than one execution context inside the same program executing at the same time.

2009-07-16T02:07:00.000-07:00

2. Process Scheduling

Scheduling Queues

Job queue – set of all processes in the system.
Ready queue – set of all processes residing in main memory, ready and waiting to execute.

Ready Queue And Various I/O Device Queues

Device queues – set of processes waiting for an I/O device.

Processes migrate between the various queues.

Schedulers

Long-term scheduler (or job scheduler) – selects which processes should be brought into the ready queue.

Short-term scheduler (or CPU scheduler) – selects whichprocess should be executed next and allocates CPU.

Short-term scheduler is invoked very frequently

(milliseconds)=> (must be fast).

Long-term scheduler is invoked very infrequently

(seconds, minutes) =>(may be slow).

The long-term scheduler controls the degree of multiprogramming.

Processes can be described as either:

I/O-bound process – spends more time doing I/O than computations, many short CPU bursts.
CPU-bound process – spends more time doing computations; few very long CPU bursts.

Context Switch

When CPU switches to another process, the system must save the state of the old process and load the saved state for the new process.

Context-switch time is overhead; the system does no useful work while switching.

Time dependent on hardware support.

2009-07-16T01:57:00.000-07:00

3.)Operations on Processes

--Process Creation

Parent process creates children processes, which, in turn create other processes, forming a tree of processes.
Resource sharing

Parent and children share all resources.
Children share subset of parent’s resources.
Parent and child share no resources.

3. Execution

Parent and children execute concurrently.
Parent waits until children terminate.

4.Address space

Child duplicate of parent.
Child has a program loaded into it.

UNIX examples

fork system call creates new process
fork returns 0 to child , process id of child for parent
exec system call used after a fork to replace the process’ memory space with a new program.

--Process Termination

Process executes last statement and asks the operating system to delete it (exit).

Output data from child to parent (via wait).
Process’ resources are deallocated by operating system.n Parent may terminate execution of children processes (abort).
Child has exceeded allocated resources.
Task assigned to child is no longer required.
Parent is exiting.

----------- Operating system does not allow child to continue if its parent terminates.

----------- Cascading termination.

In Unix, if parent exits children are assigned init as parent

2009-07-16T01:46:00.000-07:00

1. What are the major activities of an Operating System with regards to Process Management?

The operating system is responsible for the following activities in connection with process management.

Process creation and deletion.
Process suspension (process is in I/O wait queue, or “swapped” out to disk, …) and resumption (move to ready queue or execution) – manage the state of the process.

Provision of mechanisms for:
Process synchronization - concurrent processing is supported thus the need for synchronization of processes or threads.
Process communication
Deadlock handling

2009-07-16T01:43:00.000-07:00

2. What are the major activities of an Operating System with regards to Memory Management?

-Keep track of which parts of memory are currently being used and by whom.
-Decide which processes to load when memory space becomes available - long term or medium term scheduler.
-Mapping addresses in a process to absolute memory addresses - at load time or run time.
-Allocate and deallocate memory space as needed.
-Memory partitioning, allocation, paging (VM), address translation, defrag,
…Memory protection

2009-07-16T01:38:00.000-07:00

3. What are the major activities of an Operating System with regards to Secondary-Storage Management?

--Free space management
--Storage allocation
--Disk scheduling – minimize seeks (arm movement … very slow operation)
--Disk as the media for mapping virtual memory space
--Disk caching for performance
--Disk utilities: defrag, recovery of lost clusters, etc.

2009-07-16T01:35:00.000-07:00

4. What are the major activities of an Operating System with regards to File Management?

File creation and deletion - system calls or commands.
Directory creation and deletion - system calls or commands.
Support of primitives for manipulating files and directories in an efficient manner - system calls or commands.
Mapping files onto secondary storage.
File backup on stable (nonvolatile) storage media.

EX: File Allocation Table (FAT) for Windows/PC systems

2009-07-16T01:31:00.000-07:00

5. What is the purpose of the command-interpreter?

The program that reads and interprets control statements is called variously:

·command-line interpreter (Control card interpreter in the “old batch days”)

·shell (in UNIX)Command.com for external commands in DOS Its function is to get and execute the next command statement.

2009-07-07T03:58:00.000-07:00

(0) System Boot

Operating system must be made available to hardware so hardware can start it

Small piece of code – bootstrap loader, locates the kernel, loads it into memory, and starts it
Sometimes two-step process where boot block at fixed location loads bootstrap loader
When power initialized on system, execution starts at a fixed memory location
-------Firmware used to hold initial boot code

2009-07-07T03:17:00.000-07:00

(0) System Generation

(computer science) A process that creates a particular and uniquely specified operating system; it combines user-specified options and parameters with manufacturer-supplied general-purpose or nonspecialized program subsections to produce an operating system (or other complex software) of the desired form and capacity. Abbreviated sysgen.

2009-07-07T02:52:00.000-07:00

(0) Virtual Machine

A virtual machine was originally defined by Popek and Goldberg as "an efficient, isolated duplicate of a real machine". Current use includes virtual machines which have no direct correspondence to any real hardware.[1]Virtual machines are separated into two major categories, based on their use and degree of correspondence to any real machine. A system virtual machine provides a complete system platform which supports the execution of a complete operating system (OS). In contrast, a process virtual machine is designed to run a single program, which means that it supports a single process. An essential characteristic of a virtual machine is that the software running inside is limited to the resources and abstractions provided by the virtual machine -- it cannot break out of its virtual world.
A virtual machine, simply put, is a virtual computer running on a physical computer. The virtual machine emulates a physical machine in software. This includes not only the processor but the instruction set, the memory bus, any BIOS commands and critical machine hardware such as the system clock and and DMA hardware. Depending upon the machine peripheral devices are generally virtualized including storage devices like floppy drives, hard drives and CD drives. Video, keyboard and mouse support are also common. A virtual machine must look and act just like the real thing so standard software, like operating systems and applications, can run without modification.

Implementation

Modes:
>>virtual user mode and virtual monitor mode,
>>Actual user mode and actual monitor mode
Time
>>Whereas the real I/O might have taken 100 milliseconds, the virtual I/O might take less time (because it is spooled) or more time (because it is interpreted.)
>>The CPU is being multi-programmed among many virtual machines, further slowing down the virtual machines in unpredictable ways.

benefits

For testers it is important that they test software against the various supported operating systems that an application runs against. The traditional approach is to run multiple physical machines, each with a different operating system. This is bad for several reasons. Space, maintenance, power and feasibility come to mind. Deployment of the software to these various machines can also be an issue. Instead a tester can run multiple virtual machines on one physical machine. Each virtual machine could have a different operating system. The application can be deployed to the virtual machines and tested.

Another advantage of virtual machines is reproducibility. Build and test environments generally need to be well controlled. It would be undo work to have to wipe out a machine and rebuild it after each build or test run. A virtual machine allows the environment to be set up once. The environment is then captured. Any changes made after the capture can then be thrown away after the build or test run. Most emulation software packages offer this in some form or another

Two advantages
>>To provide a robust level of security
>>no direct sharing of resources.
Two solutions
>>To allow system development to be done easily
>>A perfect vehicle for OS research and development.
>>difficult to implement due to the effort required to provide an exact duplicate to the underlying machine.
>>Wine for Linux

Examples

A program written in Java receives services from the Java Runtime Environment (JRE) software by issuing commands to, and receiving the expected results from, the Java software. By providing these services to the program, the Java software is acting as a "virtual machine", taking the place of the operating system or hardware for which the program would ordinarily be tailored.

2009-07-03T01:13:00.000-07:00

(0) System Structure

Simple Structure

-any part of the system may use the functionality of the rest ofthe system

-MS-DOS (user programs can call low level I/O routines)View the OS as a series of levels

–Each level performs a related subset of functions

–Each level relies on the next lower level to perform more primitive functions

–This decomposes a problem into a number of more manageable subproblems

Layered Approach

The operating system is divided into a number of layers (levels), each built on top of lower layers. The bottom layer (layer 0), is the hardware; the highest (layer N) is the user interface.

With modularity, layers are selected such that each uses functions (operations) and services of only lower-level layers

---Properties

Simplicity of construction
Simplicity of Debugging
Problems
Precise definition of layers
Example: Memory manager requires device driver of backing store (due to virtual memory)
The device driver requires CPU scheduler (since if the driver waits for IO, another task should be scheduled)
CPU scheduler may require virtual memory for large amount of information of some processes
Less efficiency: due to the number of layers a request should pass

2009-07-03T00:43:00.000-07:00

(0) System Calls

System calls provide the interface between a running program and the operating system

Generally available as assembly-language instructions

Languages defined to replace assembly language for systems programming allow system calls to be made directly (e.g., C, C++)

Types of System Calls

Process control

create/terminate a process (including self)

File management
Also referred to as simply a file system or filesystem. The system that an operating system or program uses to organize and keep track of files. For example, a hierarchical file system is one that uses directories to organize files into a tree structure.Although the operating system provides its own file management system, you can buy separate file management systems. These systems interact smoothly with the operating system but provide more features, such as improved backup procedures and stricter file protection.

--->>Device management

Device Management is a set of technologies, protocols and standards used to allow the remote management of mobile devices, often involving updates of firmware over the air (FOTA). The network operator, handset OEM or in some cases even the end-user (usually via a web portal) can use Device Management, also known as Mobile Device Management, or MDM, to update the handset firmware/OS, install applications and fix bugs, all over the air. Thus, large numbers of devices can be managed with single commands and the end-user is freed from the requirement to take the phone to a shop or service center to refresh or update.

Information maintenance –get time

–set system data (OS parameters)

– get process information (id, time used)

Communications

– establish a connection

– send, receive messages

– terminate a connectionlProcess control

– create/terminate a process (including self)

2009-07-02T04:23:00.000-07:00

(0)Operating System Services

Program execution – system capability to load a program into memory and to run it
I/O operations – since user programs cannot execute I/O operations directly, the operating system must provide some means to perform I/On
File-system manipulation – program capability to read, write, create, and delete files
Communications – exchange of information between processes executing either on the same computer or on different systems tied together by a network. Implemented via shared memory or message passing
Error detection – ensure correct computing by detecting errors in the CPU and memory hardware, in I/O devices, or in user programs

2009-07-02T03:03:00.000-07:00

(0) System Components

Operating System Process Management

A process is a program in execution

A process needs certain resources, including CPU time, memory, files, and I/O devices, to accomplish its task.

The operating system is responsible for the following activities in connection with process management

Process creation and deletion
Process suspension and resumption
Provision of mechanisms for:

process synchronization
process communication

Main memory Management

1.Memory is a large array of words or bytes, each with its own address

() It is a repository of quickly accessible data shared by the CPU and I/O devices

2. Main memory is a volatile storage device. It loses its contents in the case of system failure

3. The operating system is responsible for the following activities in connections with memory managementl

Keep track of which parts of memory are currently being used and by whoml
Decide which processes to load when memory space becomes availablel
Allocate and deallocate memory space as needed

Memory management is the act of managing computer memory. In its simpler forms, this involves providing ways to allocate portions of memory to programs at their request, and freeing it for reuse when no longer needed. The management of main memory is critical to the computer system.

File management

A file is a collection of related information defined by its creatorl Commonly, files represent programs (both source and object forms) and data

The operating system is responsible for the following activities in connections with file management:

File creation and deletion
Directory creation and deletion
Support of primitives for manipulating files and directories
Mapping files onto secondary storage
File backup on stable (nonvolatile) storage media

A file object provides a representation of a resource (either a physical device or a resource located on a physical device) that can be managed by the I/O system. Like other objects, they enable sharing of the resource, they have names, they are protected by object-based security, and they support synchronization. The I/O system also enables reading from or writing to the resource.

I/O System management

The I/O system consists of:

>A buffer-caching system

>A general device-driver interface

>Drivers for specific hardware devices

Secondary Storage Management

Since main memory (primary storage) is volatile and too small to accommodate all data and programs permanently, the computer system must provide secondary storage to back up main memory

Most modern computer systems use disks as the principle on-line storage medium, for both programs and datan

The operating system is responsible for the following activities in connection with disk management:

>> Free space managementl Storage allocationl

>>Disk scheduling

The I/O management subsystem controls all the input andoutput of the computer system. For the enforcement ofsecurity, the most important things that the I/O managementsubsystem does are· Managing the transfer of data.· Enforcing access controls (the DAC mechanisms) on datawhile it is being transferred. See “Discretionary access control(DAC)” for more information on DAC.During the transfer of blocks or streams of data, and duringcharacter I/O operation, each I/O transaction is completelyseparate from all others. It follows a well-known and well-defined path; therefore, the integrity of all data is maintainedduring data transactions.

Protection System

Protection refers to a mechanism for controlling access by programs, processes, or users to both system and user resourcesn

The protection mechanism must:

distinguish between authorized and unauthorized usagel specify the controls to be imposedl
provide a means of enforcement

Command-Interpreter system

Many commands are given to the operating system by control statements which deal with:

Process creation and management
I/O handling
Secondary-storage management
Main-memory management
File-system access
Protection
Networking

A command interpreter is the part of a computer operating system that understands and executes commands that are entered interactively by a human being or from a program. In some operating systems, the command interpreter is called the shell.

2009-06-25T02:56:00.000-07:00

(3) Hardware Protection

Dual Mode Operation

• Sharing system resources requires operating system to ensurethat an incorrect program cannot cause other programs toexecute incorrect

• Provide hardware support to differentiate between at least twomodes of operations.

1. User mode – execution done on behalf of a user.

2. Monitor mode (also supervisor mode or system mode) –execution done on behalf of operating system.

I/O Protection

• All I/O instructions are privileged instructions.
• Must ensure that a user program could never gain control of the computer in monitor mode (i.e., a user program that, aspart of its execution, stores a new address in the interruptvector).

Memory Protection

• Must provide memory protection at least for the interrupt vectorand the interrupt service routines.
• In order to have memory protection, add two registers thatdetermine the range of legal addresses a program may access:

– base register
– holds the smallest legal physical memoryaddress.
– limit register
– contains the size of the range.

• Memory outside the deﬁned range is protected.

CPU Protection

-to prevent a user programs gets stuck in infinite loop and never returning back to the os

2009-06-25T02:43:00.000-07:00

(2) Storage Heirarchy

caching

--->>In computer science, a cache (pronounced /kæʃ/) is a collection of data duplicating original values stored elsewhere or computed earlier, where the original data is expensive to fetch (owing to longer access time) or to compute, compared to the cost of reading the cache. In other words, a cache is a temporary storage area where frequently accessed data can be stored for rapid access. Once the data is stored in the cache, it can be used in the future by accessing the cached copy rather than re-fetching or recomputing the original data.
A cache has proven to be extremely effective in many areas of computing because access patterns in typical computer applications have locality of reference. There are several kinds of locality, but this article primarily deals with data that are accessed close together in time (temporal locality). The data might or might not be located physically close to each other (spatial locality).

coherency and consistency

In computing, cache coherence (also cache coherency) refers to the integrity of data stored in local caches of a shared resource. Cache coherence is a special case of memory coherence.
When clients in a system maintain caches of a common memory resource, problems may arise with inconsistent data. This is particularly true of CPUs in a multiprocessing system. Referring to the "Multiple Caches of Shared Resource" figure, if the top client has a copy of a memory block from a previous read and the bottom client changes that memory block, the top client could be left with an invalid cache of memory without any notification of the change. Cache coherence is intended to manage such conflicts and maintain consistency between cache and memory.

cache consistency

-->>The synchronisation of data in multiple caches such that reading a memory location via any cache will return the most recent data written to that location via any (other) cache.Some parallel processors do not cache accesses to shared memory to avoid the issue of cache coherency. If caches are used with shared memory then some system is required to detect when data in one processor's cache should be discarded or replaced because another processor has updated that memory location. Several such schemes have been devised.

Cache Consistency Mechanisms There are several ways to maintain cache consistency of files placed in a cache: time-to-live fields, active invalidation protocols, and client polling. Time-to-live fields are efficient to set up, but are inaccurate.

2009-06-25T02:29:00.000-07:00

(1) Storage Structure

main memory

--->>>Primary storage, presently known as memory, is the only one directly accessible to the CPU. The CPU continuously reads instructions stored there and executes them as required. Any data actively operated on is also stored there in uniform manner.Historically, early computers used delay lines, Williams tubes, or rotating magnetic drums as primary storage. By 1954, those unreliable methods were mostly replaced by magnetic core memory, which was still rather cumbersome. Undoubtedly, a revolution was started with the invention of a transistor, that soon enabled then-unbelievable miniaturization of electronic memory via solid-state silicon chip technology.This led to a modern random access memory (RAM). It is small-sized, light, but quite expensive at the same time. (The particular types of RAM used for primary storage are also volatile, i.e. they lose the information when not powered).

magnetic Disk

--->>>A memory device, such as a floppy disk, a hard disk, or a removable cartridge, that is covered with a magnetic coating on which digital information is stored in the form of microscopically small, magnetized needles.

--Moving Head Disk Mechanism

Magnetic tapes

--->>Magnetic tape is a medium for magnetic recording generally consisting of a thin magnetizable coating on a long and narrow strip of plastic. Nearly all recording tape is of this type, whether used for recording audio or video or for computer data storage. It was originally developed in Germany, based on the concept of magnetic wire recording. Devices that record and playback audio and video using magnetic tape are generally called tape recorders and video tape recorders respectively. A device that stores computer data on magnetic tape can be called a tape drive, a tape unit, or a streamer.
Magnetic tape revolutionized the broadcast and recording industries. In an age when all radio (and later television) was live, it allowed programming to be prerecorded. In a time when gramophone records were recorded in one take, it allowed recordings to be created in multiple stages and easily mixed and edited with a minimal loss in quality between generations. It is also one of the key enabling technologies in the development of modern computers. Magnetic tape allowed massive amounts of data to be stored in computers for long periods of time and rapidly accessed when needed.

2009-06-24T20:14:00.000-07:00

5. Device Status Table.

--->>Device-status table contains entry for each I/O deviceindicating its type, address, and state.

2009-06-24T20:07:00.000-07:00

1. Bootstrap Program

---->>In computing, bootstrapping (from an old expression "to pull oneself up by one's bootstraps") is a technique by which a simple computer program activates a more complicated system of programs. In the start up process of a computer system, a small program such as BIOS, initializes and tests that hardware, peripherals and external memory devices are connected, then loads a program from one of them and passes control to it, thus allowing loading of larger programs, such as an operating system.
A different use of the term bootstrapping is to use a compiler to compile itself, by first writing a small part of a compiler of a new programming language in an existing language to compile more programs of the new compiler written in the new language. This solves the "chicken and egg" causality dilemma.

2009-06-23T04:23:00.000-07:00

2. Difference of Interrupt and trap and their use.

---->>In computing, an interrupt is an asynchronous signal indicating the need for attention or a synchronous event in software indicating the need for a change in execution.
A hardware interrupt causes the processor to save its state of execution via a context switch, and begin execution of an interrupt handler.
Software interrupts are usually implemented as instructions in the instruction set, which cause a context switch to an interrupt handler similar to a hardware interrupt.
Interrupts are a commonly used technique for computer multitasking, especially in real-time computing. Such a system is said to be interrupt-driven.An act of interrupting is referred to as an interrupt request (IRQ).

---->>In computing and operating systems, a trap is a type of synchronous interrupt typically caused by an exceptional condition (e.g. division by zero or invalid memory access) in a user process. A trap usually results in a switch to kernel mode, wherein the operating system performs some action before returning control to the originating process. In some usages, the term trap refers specifically to an interrupt intended to initiate a context switch to a monitor program or debugger.
In SNMP, a trap is a type of PDU used to report an alert or other asynchronous event about a managed subsystem.

2009-06-23T04:20:00.000-07:00

4.User Mode

---->>In User mode, the executing code has no ability to directly access hardware or reference memory. Code running in user mode must delegate to system APIs to access hardware or memory. Due to the protection afforded by this sort of isolation, crashes in user mode are always recoverable. Most of the code running on your computer will execute in user mode.

2009-06-23T04:08:00.000-07:00

3.Monitor mode

--->>Monitor mode, or RFMON (Radio Frequency Monitor) mode, allows a computer with a wireless network interface card (NIC) to monitor all traffic received from the wireless network. Unlike promiscuous mode, which is also used for packet sniffing, monitor mode allows packets to be captured without having to associate with an access point or ad-hoc network first. Monitor mode only applies to wireless networks, while promiscuous mode can be used on both wired and wireless networks. Monitor mode is one of the six modes that 802.11 wireless cards can operate in: Master (acting as an access point), Managed (client, also known as station), Ad-hoc, Mesh, Repeater, and Monitor mode.Monitor mode, or RFMON (Radio Frequency Monitor) mode, allows a computer with a wireless network interface card (NIC) to monitor all traffic received from the wireless network. Unlike promiscuous mode, which is also used for packet sniffing, monitor mode allows packets to be captured without having to associate with an access point or ad-hoc network first. Monitor mode only applies to wireless networks, while promiscuous mode can be used on both wired and wireless networks. Monitor mode is one of the six modes that 802.11 wireless cards can operate in: Master (acting as an access point), Managed (client, also known as station), Ad-hoc, Mesh, Repeater, and Monitor mode.

2009-06-23T04:04:00.000-07:00

6. Direct Memory Access

---->>Direct memory access (DMA) is a feature of modern computers and microprocessors that allows certain hardware subsystems within the computer to access system memory for reading and/or writing independently of the central processing unit. Many hardware systems use DMA including disk drive controllers, graphics cards, network cards and sound cards. DMA is also used for intra-chip data transfer in multi-core processors, especially in multiprocessor system-on-chips, where its processing element is equipped with a local memory (often called scratchpad memory) and DMA is used for transferring data between the local memory and the main memory. Computers that have DMA channels can transfer data to and from devices with much less CPU overhead than computers without a DMA channel. Similarly a processing element inside a multi-core processor can transfer data to and from its local memory without occupying its processor time and allowing computation and data transfer concurrency.
Without DMA, using programmed input/output (PIO) mode for communication with peripheral devices, or load/store instructions in the case of multicore chips, the CPU is typically fully occupied for the entire duration of the read or write operation, and is thus unavailable to perform other work. With DMA, the CPU would initiate the transfer, do other operations while the transfer is in progress, and receive an interrupt from the DMA controller once the operation has been done. This is especially useful in real-time computing applications where not stalling behind concurrent operations is critical. Another and related application area is various forms of stream processing where it is essential to have data processing and transfer in parallel, in order to achieve sufficient throughput.

2009-06-23T03:57:00.000-07:00

7. Difference of RAM and DRAM.

--->>Random-access memory (usually known by its acronym, RAM) is a form of computer data storage. Today, it takes the form of integrated circuits that allow stored data to be accessed in any order (i.e., at random). The word random thus refers to the fact that any piece of data can be returned in a constant time, regardless of its physical location and whether or not it is related to the previous piece of data.[1]
By contrast, storage devices such as tapes, magnetic discs and optical discs rely on the physical movement of the recording medium or a reading head. In these devices, the movement takes longer than data transfer, and the retrieval time varies based on the physical location of the next item.
The word RAM is often associated with volatile types of memory (such as DRAM memory modules), where the information is lost after the power is switched off. Many other types of memory are RAM, too, including most types of ROM and flash memory called NOR-Flash.

---->>Dynamic random access memory (DRAM) is a type of random access memory that stores each bit of data in a separate capacitor within an integrated circuit. Since real capacitors leak charge, the information eventually fades unless the capacitor charge is refreshed periodically. Because of this refresh requirement, it is a dynamic memory as opposed to SRAM and other static memory.
The advantage of DRAM is its structural simplicity: only one transistor and a capacitor are required per bit, compared to four transistors in SRAM. This allows DRAM to reach very high density. Unlike Flash memory, it is volatile memory (cf. non-volatile memory), since it loses its data when the power supply is removed.

2009-06-23T03:51:00.000-07:00

8. Main memory

--->>>Primary storage, presently known as memory, is the only one directly accessible to the CPU. The CPU continuously reads instructions stored there and executes them as required. Any data actively operated on is also stored there in uniform manner.
Historically, early computers used delay lines, Williams tubes, or rotating magnetic drums as primary storage. By 1954, those unreliable methods were mostly replaced by magnetic core memory, which was still rather cumbersome. Undoubtedly, a revolution was started with the invention of a transistor, that soon enabled then-unbelievable miniaturization of electronic memory via solid-state silicon chip technology.
This led to a modern random access memory (RAM). It is small-sized, light, but quite expensive at the same time. (The particular types of RAM used for primary storage are also volatile, i.e. they lose the information when not powered).

2009-06-23T03:49:00.000-07:00

9. Magnetic Disk

--->>Magnetic storage and magnetic recording are terms from engineering referring to the storage of data on a magnetized medium. Magnetic storage uses different patterns of magnetization in a magnetizable material to store data and is a form of non-volatile memory. The information is accessed using one or more read/write heads. As of 2009, magnetic storage media, primarily hard disks, are widely used to store computer data as well as audio and video signals. In the field of computing, the term magnetic storage is preferred and in the field of audio and video production, the term magnetic recording is more commonly used. The distinction is less technical and more a matter of preference.

2009-06-23T03:34:00.000-07:00

10. Storage Heirarchy

---->>>The hierarchical arrangement of storage in current computer architectures is called the memory hierarchy. It is designed to take advantage of memory locality in computer programs. Each level of the hierarchy has the properties of higher bandwidth, smaller size, and lower latency than lower levels.
Most modern CPUs are so fast that for most program workloads, the locality of reference of memory accesses and the efficiency of the caching and memory transfer between different levels of the hierarchy are the practical limitation on processing speed. As a result, the CPU spends much of its time idling, waiting for memory I/O to complete. This is sometimes called the space cost, as a larger memory object is more likely to overflow a small/fast level and require use of a larger/slower level.

2009-06-22T01:55:00.001-07:00

3.) What's the diference between Batch System, Multiprogrammed system and Time-sharing system?

---A batch system is one in which jobs are bundled together with the instructions necessary to allow them to be processed without intervention

---As machines with more and more memory became available, it was possible to extend the idea of multiprogramming (or multiprocessing) as used in spooling batch systems to create systems that would load several jobs into memory at once and cycle through them in some order, working on each one for a specified period of time

---The first involved timesharing or timeslicing. The idea of multiprogramming was extended to allow for multiple terminals to be connected to the computer, with each in-use terminal being associated with one or more jobs on the computer. The operating system is responsible for switching between the jobs, now often called processes, in such a way that favored user interaction. If the context-switches occurred quickly enough, the user had the impression that he or she had direct access to the computer.

2009-06-22T01:54:00.000-07:00

4.) Advantages of Parallel systems.

-->Parallel processing is much faster than sequential processing when it comes to doing repetitive calculations on vast amounts of data. This is because a parallel processor is capable of multithreading on a large scale, and can therefore simultaneously process several streams of data. This makes parallel processors suitable for graphics cards since the calculations required for generating the millions of pixels per second are all repetitive. GPUs can have over 200 cores to help them in this.The CPU of a normal computer is a sequential processor - it's good in processing data one step at a time. This is needed in cases where the calculation the processor is performing depends on the result of the previous calculation and so on; in parallel processing these kinds of calculations will slow it down, which is why CPUs are generally optimised for sequential operations and have only 1-8 cores.In summary, the one advantage of parallel processing is that it is much faster (about 200 times faster in the best cases) for simple, repetitive calculations on vast amounts of similar data.

2009-06-22T01:51:00.000-07:00

5.) Differentiate Symmetric multiprocessing and Assymetric Multiprocessing.

--->>In computing, symmetric multiprocessing or SMP involves a multiprocessor computer-architecture where two or more identical processors can connect to a single shared main memory. Most common multiprocessor systems today use an SMP architecture. In the case of multi-core processors, the SMP architecture applies to the cores, treating them as separate processors. SMP systems allow any processor to work on any task no matter where the data for that task are located in memory; with proper operating system support, SMP systems can easily move tasks between processors to balance the workload efficiently.While

Asymmetric multiprocessing or ASMP is a type of multiprocessing supported in DEC's VMS V.3 as well as a number of older systems including TOPS-10 and OS-360. It varies greatly from the standard processing model that we see in personal computers today. Due to the complexity and unique nature of this architecture, it was not adopted by many vendors or programmers during its brief stint between 1970 - 1980.

---->>Where as a symmetric multiprocessor or SMP treats all of the processing elements in the system identically, an ASMP system assigns certain tasks only to certain processors. In particular, only one processor may be responsible for fielding all of the interrupts in the system or perhaps even performing all of the I/O in the system. This makes the design of the I/O system much simpler, although it tends to limit the ultimate performance of the system. Graphics cards, physics cards and cryptographic accelerators which are subordinate to a CPU in modern computers can be considered a form of asymmetric multiprocessing.[citation needed] SMP is extremely common in the modern computing world, when people refer to "multi core" or "multi processing" they are most commonly referring to SMP

2009-06-22T01:48:00.000-07:00

6.) Differentiate client-server systems and peer-to-peer systems.

---Client-server computing or networking is a distributed application architecture that partitions tasks or work loads between service providers (servers) and service requesters, called clients.[1] Often clients and servers operate over a computer network on separate hardware. A server is a high-performance host that is a registering unit and shares its resources with clients. A client does not share any of its resources, but requests a server's content or service function. Clients therefore initiate communication sessions with servers which await (listen to) incoming requests.

---Peer-to-p eer (P2P) networking is a method of delivering computer network services in which the participants share a portion of their own resources, such as processing power, disk storage, network bandwidth, printing facilities. Such resources are provided directly to other participants without intermediary network hosts or servers.[1] Peer-to-peer network participants are providers and consumers of network services simultaneously, which contrasts with other service models, such as traditional client-server computing.

2009-06-22T01:46:00.000-07:00

7.) Differentiate the design issues of OS between a stand-alone PC and a Workstation connected to a network.

-->>A stand-alone PC works on its own. While in a workstation connected to a network, you can freely share your files and databases to other PC.A desktop or laptop computer that is used on its own without requiring a connection to a local area network (LAN) or wide area network (WAN). Although it may be connected to a network, it is still a stand-alone PC as long as the network connection is not mandatory for its general use.In offices throughout the 1990s, millions of stand-alone PCs were hooked up to the local network for file sharing and mainframe access. Today, computers are commonly networked in the home so that family members can share an Internet connection as well as printers, scanners and other peripherals. When the computer is running local applications without Internet access, the machine is technically a stand-alone PC. A workstation is a high-end microcomputer designed for technical or scientific applications. Intended primarily to be used by one person at a time, they are commonly connected to a local area network and run multi-user operating systems. The term workstation has also been used to refer to a mainframe computer terminal or a PC connected to a network.

2009-06-22T01:43:00.000-07:00

8.) Define the essential properties of the ff. types of OS:

---Batch- Jobs with similar needs are batched together and run through the computer as a group, by an operator or automatic job sequencer. Performance is increased by attempting to keep CPU and I/O devices busy at all times through buffering, off-line operation, spooling, and multiprogramming.

---Time-Sharing- The first involved timesharing or timeslicing. The idea of multiprogramming was extended to allow for multiple terminals to be connected to the computer, with each in-use terminal being associated with one or more jobs on the computer. The operating system is responsible for switching between the jobs, now often called processes, in such a way that favored user interaction. If the context-switches occurred quickly enough, the user had the impression that he or she had direct access to the computer.

---Real-time-A real-time computer is one that execute programs that are guaranteed to have an upper bound on tasks that they carry out. Usually it is desired that the upper bound be very small. Examples included guided missile systems and medical monitoring equipment. The operating system on real-time computers is severely constrained by the timing requirements.

---Network- networked systems consist of multiple computers that are networked together, usually with a common operating system and shared resources. Users, however, are aware of the different computers that make up the system.

---Distributed- also consist of multiple computers but differ from networked systems in that the multiple computers are transparent to the user. Often there are redundant resources and a sharing of the workload among the different computers, but this is all transparent to the user.

---Handheld- designed to provide an environm,ent in which a user easily interface with the computer to execute programs.

2009-06-22T01:42:00.000-07:00

2.)Explain the goals of OS
--->>Execute user programs and make solving user problems easier.
--->>make the computer system convenient to use.

2009-06-22T01:39:00.000-07:00

1.) what is the difference of OS in terms of uer's view and system's view?

-->In user's view, Operating system is designed mostly for ease of use, with some attention to performance and none to resource utilization. While in system's view, operating system is serve as resource allocator.

-->User view

The user view of the computer varies by the interface being used. Most computer users sit in front of a PC, consisting of a monitor, keyboard, mouse and system unit. Such a system is designed for one user to monopolize its resources, to maximize the work that the user is performing. In this case,the operating system is designed mostly for ease of use, with some attention paid to performance, and none paid to resource utilization.

--->System View

We can view an operating system as a resource allocator. A computer system has many resources - hardware and software - that may be required to solve a problem. The operating system acts as the manager of these resources.An operating system can also be viewed as a control program that manages the execution of user programs to prevent errors and improper use of the computer. It is especially concerned with the operation and control of I/O devices.

2009-02-25T02:03:00.000-08:00

Questions to be answered.
1. What is the reason for technicians to wear special wrist grounding straps?
2. After installing a new computer component why is it important to obtain the most current driver for it?
3. What are the steps required to install a peripheral device?
4. If a newly installed peripheral device does not function properly what steps can be taken to correct the problem?
5. Explain the technique used to help protect data on a hard drive when doing a clean install?
6. Explain what a software patch is.

1.Anti-Static Wrist Strap

Worn by computer technicians to prevent damaging static discharge while working on static-sensitive equipment. Antistatic Wrist Straps work continuously, discharging electricity harmlessly as it's generated. A must for anyone who frequently works inside a computer. All wrist straps include a grounding cord attachment
Electrostatic Protection Wrist Strap: Required
Used to safely dissipate static electricity so that it does not damage sensitive electronic equipment. Do not get the self-contained type that claim to dissipate static electricity without being connected to ground; they do not work as well as their wired counterparts.

source:http://www.google.com/search?hl=en&q=computer+technician+wrist+strap%28definition%29

2. After installing a new computer component why is it important to obtain the most current driver for it?

----ans. it is important to obtain the most current driver for the reason that the manufacturers of the new computer component updates new driver which is compatible for it.There are also new features added for it.

A device driver is a program that controls a particular type of device that is attached to your computer. There are device drivers for printers, displays, CD-ROM readers, diskette drives, and so on. When you buy an operating system, many device drivers are built into the product. However, if you later buy a new type of device that the operating system didn't anticipate, you'll have to install the new device driver. A device driver essentially converts the more general input/output instructions of the operating system to messages that the device type can understand.
Some Windows programs are virtual device drivers. These programs interface with the Windows Virtual Machine Manager. There is a virtual device driver for each main hardware device in the system, including the hard disk drive controller, keyboard, and serial and parallel ports. They're used to maintain the status of a hardware device that has changeable settings. Virtual device drivers handle software interrupts from the system rather than hardware interrupts.
In Windows operating systems, a device driver file usually has a file name suffix of DLL or EXE. A virtual device driver usually has the suffix of VXD.

Source:http://searchenterprisedesktop.techtarget.com/sDefinition/0,,sid192_ gci211938,00.html

3 Step in Installing a Peripheral

A computer device, such as a CD-ROM drive or printer, that is not part of the essential computer, i.e., the memory and microprocessor. Peripheral devices can be external -- such as a mouse, keyboard, printer, monitor, external Zip drive or scanner -- or internal, such as a CD-ROM drive, CD-R drive or internal modem. Internal peripheral devices are often referred to as integrated peripherals.

Adding a Peripheral Device to a System
Adding a new peripheral device that is not-pluggable usually involves the following:
Shutting down the system
Connecting the device to the system
Rebooting the system

How to Add a Peripheral Device to add the following devices that are not hot-pluggable to a system:

C D-ROM
Secondary disk drive
Tape drive
SBUS card
In some cases, you might have to add a third-party device driver to support the new device.

How to Add a Peripheral Device

1. Become superuser.
2.(Optional) If you need to add a device driver to support the device,

complete the procedure How to Add a Device Driver.
3. Create the /reconfigure file.
4. Shut down the system.

5. Select one of the following to turn off power to the system after it is shut down:
For SPARC platforms, it is safe to turn off power if the ok prompt is displayed.
For x86 platforms, it is safe to turn off power if the type any key to continue

prompt is displayed.

6. Turn off power to all peripheral devices.
For the location of power switches on any peripheral devices, refer to

the hardware installation guides that accompany your peripheral devices.
7.Install the peripheral device, making sure that the device you are adding has

a different target number than the other devices on the system.
Often, a small switch is located at the back of the disk for selecting the

target number.
Refer to the hardware installation guide that accompanies the peripheral

device f r information on installing and connecting the device.
8. Turn on the power to the system.
The system boots to multiuser mode, and the login prompt is displayed.
9. Verify that the peripheral device has been added by attempting to access the device.

How to Add a Device Driver
This procedure assumes that the device has already been added to the system. If not, see What You Need for Unsupported Devices.

----1.Become superuser.
----2.Place the tape, diskette, or CD-ROM into the drive.
----3.Install the driver.

----4.Verify that the package has been added correctly

source:http://searchenterprisedesktop.techtarget.com/sDefinition/0,,sid192%20_gci211938,00.html

http://www.webopedia.com/TERM/p/peripheral_device.html

4. If a newly installed peripheral device does not function properly what steps can be taken to correct the problem?

Check if the product or the hardware you bought has no defect or company defects.

You should also check for driver updates for all your peripheral devices.

If you're up to date, and you started having issues around the time you last updated a driver, try backing down to a lower version.

Source:http://www.bautforum.com/archive/index.php/t-62740.html

5.Explain the technique that can be used to help protect data on a hard drive when doing a clean install?

One of the techniques available to help protect data is to divide the hard drive into multiple partitions. With a clean install, many technicians prefer to create one partition for data and a separate partition for the OS. This enables an OS to be upgraded without the risk of losing data. It also simplifies backup and recovery of data files

source: http://www.google.com/search?

6. Explain what a software patch is.
A patch is a small piece of software designed to fix problems with or update a computer program or its supporting data. This includes fixing bugs, replacing graphics and improving the usability or performance. Though meant to fix problems, poorly designed patches can sometimes introduce new problems (see software regressions).
A patch is a piece of program code that can correct a problem or enhance the
functionality of an application program or OS. They are usually provided by the
manufacturer to repair a known vulnerability or reported problem
source:http://en.wikipedia.org/wiki/Patch_(computing)

2009-01-28T02:21:00.000-08:00

Screen shots of Operating System

1.1Window XP

Windows XP The Windows eXPerience operating system is available as home and professional edition and are similar suitable for the use on standalone computers. The home edition is suitable for user which worked with Windows 9x/ME till now and don't need special network or security features in theire environment. If the user have used Windows NT/2000 private, in business or both, the Professional Edition is not only with a view of the administration optimally. Microsoft already
RC1 2505 - Programs can specifically

be executed by another user

encloses 10,000 drivers on the installation media

of Windows XP, about the Windows update further more 2,000 drivers are available.

1.2 Window Vista

Windows Vista Microsoft published the new product name Vista for this new Windows Version on an event in the USA/Atlanta on 21-07-2005. This Windows Version was known under the development name Longhorn before. The installation of Vista is based on WIM (Windows Imaging format), a file-based Image Format. It compresses the contained files and can be used for the installation on several platforms from the same Image. The image

Beta 2 - Windows start menu

and version informationson

the DVD contains a pre-installation of the system directories of Windows in the Windows Imaging (.WIM) file and adapts to the hardware configuration.

1.3Windows 2000 Professional

Microsoft released this new Windows version 5.0, Build 2195 in February 2000. It is the desktop operating system of the new Windows 2000 platform for x86 architecture and be completed by the versions Windows 2000 Server, Windows 2000 Advanced Server and Windows 2000 Datacenter Server. As a minimum requierement for the installation a Pentium processor, 32 mbyte main memory and 650 mbyte of free hard disk storage are needed. Microsoft had planned to develop also a operating system version for the Alpha architecture, the plans were stopped after an announcement of Compaq. Compaq restricted the support to Windows NT 4.0 with service pack 6 and not higher at 1999-08-25. Microsoft stopped the development plans for the Windows 2000 32- bit of Alpha version after that.

1.4 Linux
Red Flag Linux Red Flag Software Co., Ltd. was founded of the software research institute "Chinese Academy of Sciences" and NewMargin venture capital in June 2000. Red Flag Software maintains business relations with IBM, Intel, HP, Oracle and other companys. Red Flag aimed at the implementation of buildings for training, technological support and point of sales in China and later worldwide. In several server variants they exists currently the Function Server, Database Server, Cluster Server and Webmail Server in version 3.0.

DOS and Windows

MS-DOS FDISK Main Menu
Most DOS fdisk programs, including the fdisk program that came with the original Windows 95, are only capable of creating FAT partitions of types FAT12 and FAT16.
A derivative of the MS-DOS fdisk was provided with Windows 95, Windows 98, and later Windows Me. Only those fdisk versions shipping with Windows 95B or later are able to manipulate FAT32 partitions. Windows 2000 and later do not use fdisk, they have the Logical Disk Manager feature, as well as DiskPart.
Unlike the fdisk programs for other operating systems, the fdisk programs for DOS and Windows 9x/Me not only alter data in the partition table, but will also overwrite many sectors of data in the partition itself. Users must be sure the correct disk/partition has been chosen before using a DOS/Windows fdisk for partitioning.
The implementation of fdisk in FreeDOS has many advanced features and is free software.

NOS certifications

2009-01-19T03:27:00.000-08:00

5.2.2 Worksheet: NOS Certifications and Jobs

Network Operating System(s) covered:
The Microsoft Certified Systems Engineer (MCSE) credential is the premier certification for professionals who analyze the business requirements and design and implement the infrastructure for business solutions based on the Microsoft Windows 2000 platform and Microsoft Windows Server System. Implementation responsibilities include installing, configuring, and troubleshooting network systems. Learn more about MCSE job functions by reading the MCSE Job Task Analysis (Microsoft Word 925 KB).
Courses/Training required for Certification:
Microsoft Certified Systems Engineer (MCSE) Certification
Courses/ Training required for Certification:
The Windows 2000 track of the MCSE credential is designed for information technology (IT) professionals working in the typically complex computing environment of medium to large organizations.An MCSE candidate should have at least one year of experience implementing and administering a network operating system in environments with the following characteristics:
200 to 26,000 supported users
Five to 150 physical locations
Typical network services and applications including file and print, database, messaging, proxy server or firewall, dial-in server, desktop management, and Web hosting
Connectivity needs including connecting individual offices and users at remote locations to the corporate network and connecting corporate networks to the Internet
Implementing and administering a desktop operating system
Designing a network infrastructureFor more information on additional requirements to earn the MCSE credential, see the MCSE Certification Requirements
-------------------------------------------------------------------------------------------------
Network Operating System(s) covered:
CISCO
Certification(s) title:
Cisco ASA Specialist
Cisco security certifications focus on the growing need for knowledgeable network professionals who can implement complete security solutions. The ASA Specialist certification identifies individuals who possess in-depth expertise with implementing security technologies using the Adaptive Security Appliance (ASA) technologies, especially firewall and VPN functionality. Other topics include ACL, AAA, advanced protocol handling, remote access VPN, secure socket layer VPN, site-to-site VPNs, failover, and security appliance management. Cisco ASA Specialists possess the ability to describe, configure, verify and manage the ASA products and the Adaptive Security Device Manager (ASDM).
Courses/Training required for Certification:
Cisco ASA Specialist Prerequisites: CCNA Security
Cisco ASA Specialist Exams and Recommended Training:
1. Required Exam(s)
a.)642-524 SNAF
b.)642-515 SNAA
2. Recommended Training:
a.)Securing Networks with ASA Foundation
b.)Securing Networks with ASA Advanced

Network Operating system(s) covered:

Red Hat Certified Engineer (RHCE) is a performance-based test that measures actual competency on live systems. Called the "crown jewel of Linux certifications," RHCE proves an individual's ability to configure networking services and security on servers running a Red Hat OS. RHCE was recently named the hottest certification in all of IT by CertCities.com.

Certification title:Red Hat Certified Engineer (RHCE)

Courses:Red Hat Training:Red Hat Certifications: Classroom TrainingRed Hat Training provides classroom-based courses at convenient worldwide locations and in a variety of topics. Browse through the complete list of courses below or select a track on the right-hand side of this page. Visit the Classroom Student Guide to find out more

Diagnostic Software1. Based on your research, list at least two different hard drive manufacturers.
Seagate Maxtor2
Manufacturer: Seagate Technology
Software Name: Seagate Seatools 1.1.3.2
File Name: SeatoolsForWindows.msi
File Size: 2.23 MB
Version: 1.1.3.2
Published date: February 27, 2008 updated
Description:
Seatools for Windows is a comprehensive, easy to use diagnostic tool that helps you quickly determine the condition of disc drive in your external hard drive, desktop or notebook computers. It tests USB, 1394, ATA(PATA/IDE), SATA, and SCSI drives.

Network Jobs

Sr. Network Engineer

RESPONSIBILITIES:
Responsible for day-to-day operational support of the network, troubleshooting network incidents and outages , provide on-site support for the Network Operations Center, provide hardware break-fix response, maintain network hardware inventory, and generate network
operations reports.

REQUIREMENTS:
• Bachelor’s degree with 5 years experience on implementing and
troubleshooting CISCO switches, routers and firewalls and WAN
circuits; supervisory experience is not required
• CISCO certification (CCNA) is preferred, but should have at least 1
IT certification.
• Knowledge of structure cabling systems
• Network operations (circuits, switches, routers, and firewalls)
• Innovation
• Customer focus
• Organizational/business sense
• Communication and interaction skills
• Planning and organizing
• Willing and able to work on extended hours, on GY shift and
weekends or holidays as necessary
• Willing and able to exert physical effort in the performance of
duties and responsibilities (e.g., carry and move things or move
from one area to another)
Applicants should be Filipino citizens or hold relevant residence status.

Network Administrator II

Position Title: Network Administrator II

Position Summary :

The Network Administrator is responsible for working with the Network Administration and Help Desk teams in the planning, trouble-shooting, maintenance, and administration of enterprise servers, mail systems, databases, firewalls and the core network infrastructure. In addition, the Network Administrator will work to resolve Tier 2 and Tier 3 help desk issues/requests that occur on a daily basis. The Network Administrator will also work on various IT projects when needed. Salary range begins at $24.94 per hour. Hours are Monday through Friday with some on-call night and weekend duties as needed. The position is salaried and full-time with benefits.

Education/Experience

HS diploma or GED required MCSE or CCNA Certification preferred.
7 years IT experience in small to medium sized organizations.
5 years experience designing, administering, and implementing Exchange deployments.
5 years experience designing, administering, and implementing

Windows, Citrix or UNIX server deployments.
5 years experience administering Microsoft SQL or Oracle database solutions.
5 years experience deploying desktop solutions in a Macintosh/PC or

cross platform environment.
5 years experience administering TCP/IP networks.
Preferred experience designing and implementing Active Directory

and/or LDAP services.
MCSE or CCNA Certification preferred. Skills and Competencies

Manufacturer: western digital
Data Lifeguard Tools 11.2 for Windows

File Name: Dlgsetup11_win.zipFile Size: 3.50

MBVersion: Version 11.2

Publish Date: April, 2006

Description:The downloadable Data Lifeguard Tools now comes in both DOS and Windows versions and was written specifically for the installation of Western Digital EIDE hard drives. If your computer system already has a hard drive installed with an operating system of Windows 98SE or greater, you should use the Windows version of Data Lifeguard for best results. The DOS version is required if installing a hard drive in a new system without existing operating system support. If you plan on copying the contents of a boot drive, Western Digital recommends using the DOS version of Data Lifeguard Tools.
Manufacturer: MaxtorSoftware

Name: SCSIMax

File Name: SCSIMax.exeFile Size: 70.0

kbVersion: v1.21

Publish Date: 05.14.2003

Description: SCSiMax is a diagnostic utility for all Maxtor/Quantum@ SCSI Hard Disk Drive supporting self-monitoring, analysis, and reporting technology (S.M.A.R.T.). This test will determine Hard Drive integrity in a short period of time, with a high degree of confidence.

Latest Products

2008-11-17T02:02:00.000-08:00

Hardware Latest Processor

1.1 Desktop Processors

--> Intel® Core™ i7 Processor Extreme Edition The highest performing desktop processor on the planet.¹

Wield the ultimate gaming weapon
Conquer the world of extreme gaming with the fastest performing processor on the planet: the Intel® Core™ i7 processor Extreme Edition.¹ With faster, intelligent multi-core technology that accelerates performance to match your workload, it delivers an incredible breakthrough in gaming performance.
But performance doesn't stop at gaming. You'll multitask 25 percent faster and unleash incredible digital media creation with up to 79 percent faster video encoding and up to 46 percent faster image rendering, plus incredible performance for photo retouching and editing.¹
In fact, you'll experience maximum performance for whatever you do, thanks to the combination of Intel® Turbo Boost technology² and Intel® Hyper-Threading technology (Intel® HT technology)³, which activates full processing power exactly where and when you need it most.
Product information
3.20 GHz core speed
8 processing threads with Intel® HT technology
8 MB of Intel® Smart Cache
3 Channels of DDR3 1066 MHz memory

1.2 Servers processor

--> Intel® Itanium® Processor 9000 SequenceMission-Critical Servers and RISC Replacement We have simplified our processor brands. Documentation for the Intel® Itanium® processor now also applies to Itanium processors of the same model number.

Itanium®-based servers deliver the scalable performance, reliability, and headroom for your most compute-intensive workloads, including direct replacement for RISC and mainframe platforms. Because Itanium processors are available in commercial off-the-shelf hardware from a rich ecosystem of system and solution providers, they can quickly meet mission-critical needs.Itanium-based servers are incredibly scalable, allowing configuration in systems of as many as 512 processors and a full petabyte (1024TB) of RAM. Together with full support for both 32-bit and 64-bit applications, that capacity provides unmatched flexibility in tailoring systems to your enterprise needs.

1.3 Notebook Processors

Intel® Core™2 Extreme quad-core mobile processor (QX9300)
Achieving clock speeds of up to 2.53GHz, along with an astounding 12 MB of shared L2 cache and a 1066 MHz Front Side Bus (FSB), the Intel Core 2 Extreme quad-core mobile processor is your ultimate engine for hi-def multimedia while powering the latest generation of hardcore games.
The Intel Core 2 Extreme quad-core mobile processor has four cores processing multiple threads and multiple tasks at blistering speeds for an incredible "like you're there" experience in advanced artificial intelligence (AI), particle systems, dynamic physics, and texture generation. As your ultimate engine for creating rich, HD videos with up to 50 percent faster performance when encoding³ and editingΩ video, these processors enable you to perform like a multiple armed monster.

Component
45nm Intel® quad-core processor(QX9300)45nm Intel® dual-core processor (X9100)
Benefit :Enabled by new hafnium-based circuitry, the processors provide dynamically increased energy efficiency and greater performance in gaming, multimedia, and multitasking on the go.

Component
Power-Optimized 1066 MHz Front Side Bus (FSB)
Benefit:Increased process system bus speed provides increased data bus bandwidth vs. prior generations for incredible gaming performance.

1.4Expansion slot

PCI Express : Expansion Backplanes

PCIe-417 x16 PCI Express Expansion Backplane

Features

x16 Upstream Port

x16 PCI Express Cable Interface from Host
One or Three Meter Cable from Host

Four PCIe Expansion Slots

x16 PCI Express Slot (Double Width)
x8 PCI Express Slot (Double Width - x16 Connector)
x4 PCI Express Slot (Single Width - x8 Connector)
x4 PCI Express Slot (Singel Width - x8 Connector)

One 48 Lane PCI Express Switches supporting:

Non-Transparent Bridging for Peer-to-Peer Communications
Non-Blocking Switch Fabric
Data Integrity
Quality of Service

ATX Form Factor

Latest Operating System form SUN...

Solaris is a Unix-based operating system introduced by Sun Microsystems in 1992 as the successor to SunOS.

Solaris is known for its scalability, especially on SPARC systems, as well for being the origin for many innovative features such as DTrace and ZFS.^[1]^[2] Solaris supports SPARC-based and x86-based workstations and servers from Sun and other vendors, with efforts underway to port to additional platforms.

Solaris is certified against the Single Unix Specification. Although it was historically developed as proprietary software, it is supported on systems manufactured by all major server vendors, and the majority of its codebase is now open source software via the OpenSolaris project.

Latest Operating System Window 7

Windows 7 (formerly codenamed Blackcomb and Vienna) is the next release of M icrosoft Windows, an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops, Tablet PCs, and media center PCs.^[1]

Microsoft stated in 2007 that it is planning Windows 7 development for a three-year time frame starting after the release of its predecessor, Windows Vista, but that the final release date will be determined by product quality.^[2]

Unlike its predecessor, Windows 7 is intended to be an incremental upgrade with the goal of being fully compatible with existing device drivers, applications, and hardware.^[3] Presentations given by the company in 2008 have focused on multi-touch support, a redesigned Windows Shell with a new taskbar, a home networking system called HomeGroup,^[4] and performance improvements. Some applications that have been included with prior releases of Microsoft Windows, most notably Windows Mail, Windows Calendar,^{[citation needed]} Windows Movie Maker, and Windows Photo Gallery, are no longer included with the operating system; they are instead offered separately (free of charge) as part of the Windows Live Essentials suite.^[5]

Faster, more responsive performance

Nobody likes to wait. So we've focused on the basics that can impact the speed of your PC. Windows 7 starts up, shuts down, resumes from standby, and responds faster. You'll have fewer interruptions and can recover more quickly from problems when they do occur because Windows 7 will help you fix them when you want.

Mandriva (Mandrake Linux)

MandrakeSoft was founded in France in 1998. With the distribution Mandrake Linux based on Linux and configuration tools of its own as well as specified KDE surface the target was put to be installable as simply as possible operably and without problems. RPM is used as a packet format for software, one recognizes the precompiled software by the code contained in the package name, 'mdk', for Mandrake Linux. It is available as a desktop and server version. Mandriva Linux 2007 is available in 3 versions. The Discovery Pack is designed for beginners, Powerpack is aimed to to the advanced user and Powerpack+ for SOHO user. The GNOME 2.16 or KDE 3.5.4 desktop can be used on AIGLX and Xgl with 3D functions. A complete DVD video player is available with LinDVD, with Cedega of TransGaming PC Windows games are playable.

How can I install Windows XP Pro on my computer?

Step #1: Plan your installation

When you run the Windows XP Professional Setup program, you must provide information about how to install and configure the operating system. Thorough planning can make your installation of Windows XP Professional more efficient by helping you to avoid potential problems during installation. An understanding of the configuration options will also help to ensure that you have properly configured your system.

I won't go into that part right now but here are some of the most important things you should take into consideration when planning for your XP installation:

Check System Requirements
Check Hardware and Software Compatibility
Determine Disk Partitioning Options
Choose the Appropriate File System: FAT, FAT32, NTFS
Decide on a Workgroup or Domain Installation
Complete a Pre-Installation Checklist

Step #2: Beginning the installation process

You can install Windows XP in several methods - all are valid and good, it all depends upon your needs and your limitations.

Manual installations usually come in 3 flavors:
Boot from CD - No existing partition is required.
Boot from the 6 Setup Boot Disks, then insert the CD - No existing partition is required
Boot from an MS-DOS startup floppy, go to the command prompt, create a 4GB FAT32 partition with FDISK, reboot, format the C partition you've created, then go to the CD drive, go into the I386 folder, and run the WINNT.EXE command.
Run an already installed OS, such as Windows NT 4.0 Server. From within NT 4.0 go to the I386 folder in the W2K installation CD and run the WINNT32.EXE command.
If you want to upgrade a desktop OS such as Windows 98 into Windows 2000 Professional you can follow the same procedure as above (You cannot upgrade Windows 98 into W2K Server).

There are other non-manual installation methods, such as using an unattended file along with a uniqueness database file, using Sysprep, using RIS or even running unattended installations from within the CD itself, but we won't go into that right now.

Step #3: The text-based portion of the Setup program

The setup process begins loading a blue-looking text screen (not GUI). In that phase you will be asked to accept the EULA and choose a partition on which to install XP, and if that partition is new, you'll be asked to format it by using either FAT, FAT32 or NTFS.

Start the computer from the CD.
You can press F6 if you need to install additional SCSI adapters or other mass-storage devices. If you do you will be asked to supply a floppy disk with the drivers and you CANNOT browse it (or a CD for that matter). Make sure you have one handy.
If you want, you can press F2 to run the ASR sequence. For that you need a good backup created by the Windows XP backup program, and the ASR floppy disk. If you plan to install a new copy of XP - don't do anything.
Setup will load all the needed files and drivers.
Select To Setup Windows XP Professional Now. If you want, and if you have a previous installation of XP, you can try to fix it by pressing R. If not, just press ENTER.
Read and accept the licensing agreement and press F8 if you accept it.
Select or create the partition on which you will install Windows XP Professional. Depending upon your existing disk configuration choose one of the following:

If the hard disk is unpartitioned, you can create and size the partition on which you will install Windows XP Professional.
If the hard disk is already partitioned, but has enough unpartitioned disk space, you can create an additional partition in the unpartitioned space.
If the hard disk already has a partition that is large enough, you can install Windows XP Professional on that partition. If the partition has an existing operating system, you will overwrite that operating system if you accept the default installation path. However, files other than the operating system files, such as program files and data files, will not be overwritten.
If the hard disk has an existing partition, you can delete it to create more unpartitioned space for the new partition. Deleting an existing partition erases all data on that partition.

If you select a new partition during Setup, create and size only the partition on which you will install Windows XP Professional. After installation, use Disk Management to partition the remaining space on the hard disk.

Select a file system for the installation partition. After you create the partition on which you will install Windows XP Professional, you can use Setup to select the file system with which to format the partition. Windows XP Professional supports the NTFS file system in addition to the file allocation table (FAT) and FAT32 file systems. Windows Server 2003, Windows XP Professional, Windows 2000, and Windows NT are the only Microsoft operating systems that you can use to gain access to data on a local hard disk that is formatted with NTFS. If you plan to gain access to files that are on a local Windows XP Professional partition with the Microsoft Windows 95 or Windows 98 operating systems, you should format the partition with a FAT or FAT32 file system. We will use NTFS.

Setup will then begin copying necessary files from the installation point (CD, local I386 or network share).
Note: If you began the installation process from an MS-DOS floppy, make sure you have and run SMARTDRV from the floppy, otherwise the copying process will probably last more than an hour, perhaps even more. With SMARTDRV (or if setup was run by booting from CD) the copying will probably last a few minutes, no more than 5 max.

The computer will restart in graphical mode, and the installation will continue.

Step #4: The GUI-based portion of the Setup program

Click Customize to change regional settings, if necessary.

Current System Locale - Affects how programs display dates, times, currency, and numbers. Choose the locale that matches your location, for example, French (Canada).

Current Keyboard Layout - Accommodates the special characters and symbols used in different languages. Your keyboard layout determines which characters appear when you press keys on the keyboard.
Type your name and organization.
Type the product key.
Type the computer name and a password for the local Administrator account. The local Administrator account resides in the SAM of the computer, not in Active Directory. If you will be installing in a domain, you need either a pre-assigned computer name for which a domain account has been created, or the right to create a computer account within the domain.
Select the date, time, and time zone settings.
Setup will now install the networking components.
One thing you CAN do (you don't have to do it, it's your call - read more about it on the Increase Internet Connection Speed in Windows XP page) is to uninstall the Qos Packet Scheduler. Click it and press the Uninstall button. If you want to keep it you can simply remove the mark from the QoS check-box. In anyway you can later install or uninstall it if you want.
Highlight the TCP/IP selection and press Properties.
In the Workgroup or Domain window enter the name of your workgroup or domain.

A workgroup is a small group of computers on a network that enables users to work together and does not support centralized administration.
A domain is a logical grouping of computers on a network that has a central security database for storing security information. Centralized security and administration are important for computers in a domain because they enable an administrator to easily manage computers that are geographically distant from each other. A domain is administered as a unit with common rules and procedures. Each domain has a unique name, and each computer within a domain has a unique name.

10.Next the setup process will finish copying files and configuring the setup.
You do not need to do anything.
11.After the copying and configuring phase is finished, if XP finds that you have a badly
configured screen resolution it will advise you to change it and ask you if you see
the new settings right.

Setup finishes and boots Windows XP.

13.A Welcome screen is the first thing you see. The computer checks your
Internet connectivity (required for the mandatory Activation and voluntary
Registration processes).

XP will ask you for the default username that will log onto this computer. You can enter as many as 5 users, but you can create more after the installation is finished.

BTW, the Administrator is not shown as a valid logon option

(read more about it on the

Add the Administrator's Account to the Welcome Screen in XP Pro page).

15.That's it! you're done!

2008-11-07T01:38:00.000-08:00

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glad to meet you my friendz