Three Main Operating Systems Computer Science Essay

Carry out a critical analysis on three chief runing systems ( Linux OS, Windows Vista and Symbiam OS ) . Compare and contrast the history, overview, system construction, procedures and togss, memory direction, application and security issue of each operating system. Remark on the strength and failing of each OS considered.Based on your group analysis proposed a new OS architecture that would integrate the strength ( s ) of the bing OS and trade with the failing ( es ) of the bing OS. For this work, you are free to utilize internet resources, research publications, books and lecture resources but proper referencing must be used.

Report demands

You are required to subject one study each group. The study should non be more than 4 A4 documents Marks would be awarded for good referencing ( You will be introduced to Harvard manner mention utilizing Endnote package – non compulsory )Note that pupils would merely be awarded maximal grade for a clear, concise, accurate and good mention write up.

Coursework: Operating Systems- State of the art

Computers have been known to be in usage for many centuries in one signifier or another. The earliest computing machine was an parallel computing machine made by the Greeks around 100BCE[ 1 ]. It has been since so that computing machines and computing machine maps have developed to what they are today. There are many Operating systems on the market today, all at competitory rates with different offers right across the universe.

With the sum of latest appliances being released every twelvemonth, it is of import to see the Operating systems of all electronic points. The three chief runing systems viing in the market today are Windows Vista, Linux and Symbian, all with specific hardware and package applications.

History of each OS

Timeline taken from: hypertext transfer protocol: // foremost Windows runing system to be released was the ‘Interface director ‘ besides referred to as Microsoft Windows in the early 1980 ‘s[ 2 ]by Microsoft, which had really limited belongingss and maps. It was around this clip that the computing machine market go competitory, as Apple computing machine had more functionality. As a consequence, Windows kept conveying out more up to day of the month runing systems to run into the terminal user demands, which have changed enormously over the old ages.

The timeline shown on the right shows the figure of runing systems that have been released by Microsoft until 2001. In 2007 Windows Vista was released and the latest version, Windows 7 is about to be released. Out of all the operating systems, Windows 98 as the most successful Os to be released and it was since so that many computing machine merchandises where released to be compatible with Windows devices and there has besides been a rises in the figure of Windows Mobile users, increasing the popularity of Windows. The tabular array below shows the market portions that Windows have had for all their Operating Systems, takenfrom hypertext transfer protocol: // # History.







August 2009August 2009February 2009December 8, 2008

All versions


10 %86.44 %93.71 %93.72 %Shortly after the debut of the first Windows OS, Linux was released in 1991[ 3 ], in Helsinki by Linus Torvalds. He developed the Unix operating system, which was a basic operating system that was compatible with different hardware[ 4 ]. Unix systems were really expensive and were based on ‘mainframes and minicomputers ‘[ 5 ]. Minix was another operating system created in effort to make cheaper and more portable version of the Unix, nevertheless it was inexpensive and had minimum maps.

Linux was developed as a consequence of uniting the package of Unix and the thought of Minix, doing it a more user friendly system, so that the Unix maps can be used at place and besides gives the terminal user a pick of package and it is besides compatible with a large scope of hardware, doing it an ideal operating system. Linux is known as ‘only runing system in the universe covering such a broad scope of hardware ‘[ 6 ]go forthing their rivals Microsoft behind. Linux besides has worked alongside with the GNU GPL ( General public licence ) to “ to incorporate GNU constituents with Linux to do a


Operating system and maps

1980Psion for PDA ‘s created by David Potter1990 ‘sEPOC ( Electronic piece of cheese )Several versions released with different Graphical user interfaces for net books, net tablets and phones.2000ER5u Ericsson R380 phone released. Games installed onto phones2001- nowadaysSymbian OS were released in legion versions for many phone companies, particularly for its spouse Nokia, with Bluetooth, back uping different linguistic communications, java support, cameras, WiFi support, memory direction and their latest map is to watch digital telecasting broadcasts.

fully-functional and free operating system ”[ 7 ]. These leads to a batch of contention with their rival Microsoft, as their operating systems are n’t free.Finally, Symbian OS is an embedded operating system and is more associated with nomadic phones and smart phones and was designed to run into the demands and carry through the manner of portable ‘pocket ‘ devices. It is the universe ‘s most popular Mobile operating system[ 8 ]. The tabular array on the right shows the development of the Symbian operating systems and how the portable devices have developed functionality. Symbian OS are chiefly used in Nokia nomadic phones, as phones are their mark market devices, unlike Windows which targets computing machines.

System construction of each OS

Windows Vista OS has aThe construction of the Linux OS is based on the Kernel, which is considered to be the bosom of the system. It controls the entree to the CPU, whose maps are to pull off memory infinite and nexus to peripherals. The construction of the OS is summarized in the diagram on the right, demoing all the beds required in the system leting the operating system to work.All Linux systems are built the same manner as other runing systems, as they all have the same maps and do the same occupation.

This increased the sum of compatibility for different package and hardware, increasing the sum of flexibleness. The operating systems are besides made up of different pieces of hardware, such as the RAM, CPU, motherboard which all allows the computing machine to run expeditiously. All computing machines have a Kernel. This acts as the interface between the hardware and the operating system, leting them to treat any input and supply the correct end product, including any peripherals that may be required. The Kernel is besides responsible for allotment of resources, such as apportioning memory to running plans and pull offing files and apportioning resource clip to each user.

A Linux OS has built in bids that are used daily by the operating system, leting basic computing machine maps to be achieved, such as file use.

UI Framework Layer ( Top )

Application Servicess Layer

Java ME

OS Services Layer

generic OS services

communications services

multimedia and artworks services

connectivity services

Base Services Layer

Kernel Services & A ; Hardware Interface Layer

The microkernel architecture means that the minimal necessary is within the meat to better hardiness, handiness, and reactivity. It contains a scheduler, memory direction, and device drivers, but other services like networking, telephone, or file system support are placed in the OS Services Layer or Base Services Layer.The Symbian OS system has a more specific construction. The beds of the OS are listed below:Taken from: hypertext transfer protocol: //symbianos.

Procedures and togss of each OS

The procedures of the three runing systems are rather different. The procedure ‘provides the resources needed to put to death a plan ‘[ 9 ]and in Windows and Linux, the plans are executed in different ways.

Both procedures and togss of an OS are described here:“ A procedure has a practical reference infinite, feasible codification, unfastened grips to system objects, a security context, a alone procedure identifier, environment variables, a precedence category, lower limit and maximal working set sizes, and at least one yarn of executing. Each procedure is started with a individual yarn, frequently called the primary yarn, but can make extra togss from any of its togss. ”[ 10 ]“ A yarn is the entity within a procedure that can be scheduled for executing. All togss of a procedure portion its practical reference infinite and system resources.

The thread context includes the yarn ‘s set of machine registries, the meat stack, a thread environment block, and a user stack in the address infinite of the yarn ‘s procedure. Togss can besides hold their ain security context. ”[ 11 ]The yarn that is used by Windows OS is the basic feasible unit, whereas the Linux OS has a somewhat different procedure. Linux systems have togss, procedures and a lightweight procedure. The tabular array below is a comparing of the togss and procedures in Windows and Linux.




CreateProcess ( )CreateProcessAsUser ( )fork ( )setuid ( )White House ( )MappableTerminateProcess ( )putting to death ( )MappableSetThreadpriority ( )GetThreadPriority ( )Setpriority ( )getPriority ( )MappableGetCurrentProcessID ( )getpid ( )MappableExitprocess ( )issue ( )MappableWaitforsingleobject ( )Waitformultipleobject ( )GetExitCodeProcess ( )waitpid ( )Using Sys V semaphores, Waitforsingleobject/multipleobjectcan be implementedContext particularGetEnvironmentVariableSetEnvironmentVariablegetenv ( )setenv ( )MappableTable 1: Procedure function[ 12 ]




CreateThreadpthread_createpthread_attr_initpthread_attr_setstacksizepthread_attr_destroyMappableThreadExitpthread_exitMappableWaitForSingleObjectpthread_joinpthread_attr_setdetachstatepthread_detachMappableSetPriorityClassSetThreadPrioritySetprioritysched_setschedulersched_setparampthread_setschedparampthread_setschedpolicypthread_attr_setschedparampthread_attr_setschedpolicyContext SpecificTable 2: Togss mapping[ 13 ]Symbian ‘s memory protection is called the yarn and unlike Windows and Linux, the togss are scheduled, doing the memory protection more effectual. This allows many procedures to be running at one time. Some platforms use active objects, as they are designed for more effectual public presentation, as they are made utilizing multi-threaded codifications. On the Symbian C++ platform, the togss are scheduled with the most of import one running foremost.[ 14 ]

Memory direction of each OS

Applications of each OS

Windows Vista is compatible with many different applications.

Microsoft office, Frontpage and Professional are particularly designed bundles to accommodate different terminal users and used for different intents. Windows comes with some criterion applications, such as Windows media participant, pigment and games pre-installed. Most electronic devices are made compatible and standard to Windows OS, such as digital cameras, mp3 participants and other accoutrements.

Security issues of each OS

Windows has been known for many security breaches by a really high figure of viruses, all at a scope of hazard degrees. The figure of hazards increased when web connexions were introduced, as this allowed the viruses to distribute quickly from one computing machine to the following, holding black effects.

Besides, entree to the Internet made all the computing machines connected at a higher hazard to viruses. As Windows is a really popular OS, with at least one computing machine in every family, means that the operating system is a popular mark for virus Godheads, with at least 1,000 new viruses being created every twelvemonth.To avoid this, Windows update plan automatically updates the computing machine with new security spots, to seek to cut down the hazard of viruses assailing your Personal computer.

Windows file permissions and Windows guardian antispyware are used to forestall unauthorised entree to files and inside informations. On the other manus, although Microsoft is taking all these safeguards, they do non look to be adequate as is quoted here:“ In an article based on a study by Symantec, has described Microsoft Windows as holding the “ fewest figure of spots and the shortest mean spot development clip of the five runing systems it monitored in the last six months of 2006. ” Furthermore the figure of exposures found in Windows has significantly increased ”[ 15 ]Besides, Linux seems to hold major defects in its system, when we are sing the possible security hazards involved as an article provinces:“ Linux security experts take issue with recent studies from and from that suggest Windows is more unafraid than Linux, based on statistics from SecurityFocus. But one Linux security guru says he ‘s seeing at least a 10 % addition in Linux security exposures reported in the last six months, largely due to greater consciousness on the portion of Linux sellers. ”[ 16 ]Most of the statement with the addition in exposures is based on the fact that virus Godheads and hackers now have such a wider scope of pick so antecedently.

With the assistance of the Internet they can entree 1000000s of computing machines around the universe. Linux security is based on the feedback of their clients, so it is merely when a job occurs and a client complains that they see the exposures and so make up one’s mind whether it is relevant, as they have a much smaller audience than Windows.



DreverPrevents automatic startup from antivirus applications, doing the phone more vulnerable to other viruses.Locknut BPrevents any applications from being installed in the phoneMabir ALapp as Cabir, except can besides be transferred by directing MMS.Fontal ACauses loss of informations and interrupts reboot filesSymbian OS were vulnerable to many viruses, due to the innovation of Bluetooth, which allowed nomadic phones to link to each other leting files to be sent and in many instances viruses to be sent.

The most popular one being a virus called ‘Cabir ‘[ 17 ], the first virus that infected nomadic phones, though it did non make any harm. To forestall this antivirus package were installed onto nomadic devices and when applications are installed, warning marks come up, so that the terminal user knows if by put ining that application their device would be at hazard of being attacked by viruses. Some phones merely allow applications with Symbian certifications to be installed. The tabular array on the left lists other viruses associated with the Symbian OS[ 18 ].

Overview of each OS

Out of all three of the Operating Systems, the best Operating system is likely Windows, as their beta testing is better than Linux or Symbian, as they are non as popular.

They all have merely every bit many security jobs, all with major defects, due to an addition in chances to do harm to a bigger audience. Symbian has a different more complicated construction, whereas the constructions for Linux and Windows have a more similar construction and procedure in footings of togss and procedures.

Proposed group OS architecture

Justification of proposed OS architecture