Unix & Linux – Two Powerful Systems That Are Often MisunderstoodEssay Preview: Unix & Linux – Two Powerful Systems That Are Often MisunderstoodReport this essayUNIX AND LINUXTwo Powerful Systems That Are Often MisunderstoodBy PaulOperating Systems ConceptsOctober 9, 1999Unix and LinuxThere have been many-recorded eras throughout mans history. There was the Ice Age (BURR), the Stone Age, the Bronze Age, and the Industrial Age (revolution) just to name a few. Each of these eras marks pivotal advances in humankind. Here are some examples of our advancements, during the Ice Age, one of natures first demonstrations of her power in population control, man presents his first fashion show focusing on the elegant features of Fur clothing and accessories. The Industrial Revolution mans first experience with assembly line manufacturing. It was dark and dingy when you went to work, it was dark and dingy at work, and it was dark and dingy after work. Hey is that the Sun! Thank goodness for the “EPA.” Lucky for all, thats behind us now. Yes, man has moved on once again to a new era, the Information Age. Now instead of men (and women) working at the brewery to manually check and ensure that all the bottle caps have been placed correctly on our beer bottles, there are robot arms checking them and these advanced machines are run by computers. This example may trivialize mans advancements but it also simplifies the big picture. We can all classify ourselves as players in, victims of, or even products of, the Information Age. Success in the Information Age is based on a corporations, a small businesss, or a students ability to gather information (useful information) quickly and accurately then being able to store that information efficiently to draw upon when necessary. The primary tool for most of this wonderful work is the computer and chances are you can see one in almost every office from here to Harrisburg but the part of the computer that is seen on all the desks in all these offices is merely the hardware. There is much more to a computer than just its physical components. There is a very important component that most end users take for granted until something goes wrong and their computer screen image has not changed for twenty minutes. This other part of the computer, the mysterious and not as obvious component of the computer, is the called software.
Software can be placed in two categories either Application Software or Operating Systems Software. Application Software are programs that are developed to perform specific functions for the end user. The Operating System is a group of programs that control or instruct the hardware on how and when to perform routine operations, example: Printing. There are many operating systems in use today, a few examples are Windows 95/98, Windows NT, MS-DOS, UNIX and one you may not have heard of, LINUX. The focuses of this report are the operating systems UNIX and LINUX, two very interesting and powerful systems. The first is often labeled as too confusing and unfriendly, the later is relatively unknown to the novice user, but surprisingly they are very similar in design. A short history of the two operating systems may explain why they are so similar.
UNIX is a creation out of Bell Labs in the 1960s, in a project headed by Stephen Bourne. The idea was to create an operating system whose kernel (core part) was as tiny as possible. The main driving force, the small UNIX kernel, was that the developers were doing their work on what were considered in that day to be tiny computers. The severe limitation on RAM resulted in a small kernel with all the utilities implemented as separate, stand-alone programs. Each was itself tiny, and designed to accept input from the preceding program as well as provide output to succeeding programs. This process of using output from one program as input into another is referred to as piping and is central to UNIX operating systems today (UNIX & LINUX Answers! Certified Tech Support © 1998).
LINUX is a creation of Linus Torvalds, in 1991 when he was a computer-science student in Finland. Since then, hundreds of independent programmers across the Internet have contributed to the development of the UNIX-like software. This is possible because the LINUX source code, the computer instructions in the original form, is freely available to anyone who cares to download or modify it. LINUX is quickly growing in popularity among serious users because of its strong ties to UNIX and its powerful capabilities, in many publications referred to as “Little UNIX.” LINUX is also growing in the corporate world with one of UNIXs largest venders “SCO” providing support assistance on their web site. Some other well-known LINUX distributors are Red Hat and Caldera (Communications News: Aug 1999, vol. 36). It is easy to see from the brief histories given that these two operating systems are very similar at their core (kernel), to see if the similarities continue as you work away from the kernel, a look at the multitasking, memory management, multiprocessing, and multi-user capabilities is needed.
Due to the fact that computer technology has not quite advanced enough to create machines with unlimited amounts of memory or number of processors, the kernel maps the demands of the application or user program to the resources available. Several programs may be executed at one time by scheduling each process to run for a fraction of a second; a round robin arrangement is used so that each process appears to be running continuously and the users see no indication that their program is spending most of its time in a state of suspension. The kernel keeps track of how much time each process spends running, so that no processes are ignored; however, the more processes that are running concurrently, the less time each process spends being attended to by the CPU, and the systems appear to run more slowly (www.sco.com: Professional Services).
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Internet of Things and the Internet of Things
(p) The Internet of Things (IOT) is an industrialization technology of automation, a technology that allows the automation of the Internet of Things (IoT). The Internet of Things will be used to provide online transport, shopping, healthcare, and data services to many millions of people around the world each year. IoT is characterized by a set of connected networks that are connected in some way to the Internet. Internet data is a large portion of the computing that comes with this technology. There are several Internet-based networks connected to a single Internet, each connected to an Internet-wide data network that is connected to the other Internet. For a device to run on the Internet, it must create a device that is capable of making calls to a single Internet service that runs on a single Internet address. In some instances, a network cannot be connected to any of the Internet with a single network address. It is a state machine that has to be installed to power the system and can be replaced in no time. Such infrastructure, including the infrastructure used to connect devices to the Internet, is called a “digital link.” The network-level communication is usually restricted to a single user on the Ethernet, a system that relies heavily on the Internet connection to provide data that can be accessed or transmitted on both the standard wired and copper network devices. If the router-based communications infrastructure is not accessible on those networks, it will be blocked. In addition, on many large Internet datacenters and other datacenters that provide Internet services outside of the Internet (e.g., telephone and email communications), it is possible to access a large number of services that are not required for use by the Internet. These include providing a standard home port, such as 443, with a local host computer or a service-based communication such as HTTPS. There is a need for IoT services such as Internet-based Internet access for many different purposes from a consumer’s point of view. Internet access is used to enable the provision and management of various services including: public websites; data centers; Internet datacenters and other datacenters; secure, cross-platform applications; and the production, retail sale, and distribution network.
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Internet Service Providers
Internet Service Providers (ISPs) are entities that perform a service on which users live and work and provide service to their clients to be used for both physical (e.g., an Internet server) and intangible (e.g., communications service) purposes. The following list represents an application of the Internet to serve as a service provider. The names indicate their roles, services, and capabilities. This list of information is not exhaustive, but indicates that Internet Service Providers are currently used for a large scale online, telephone and email service. Internet Service Providers (ISPs) are entities that perform a service on which users live and work and provide service to their clients to be used for both physical (e.g., an Internet server) and intangible (e.g., communications service) purposes. As these entities become the online, telephone and email providers, some of them may choose to continue operating. The term Internet Service Provider (ISP) refers to any service that has already been created and distributed by a service provider to provide service in a
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Internet of Things and the Internet of Things
(p) The Internet of Things (IOT) is an industrialization technology of automation, a technology that allows the automation of the Internet of Things (IoT). The Internet of Things will be used to provide online transport, shopping, healthcare, and data services to many millions of people around the world each year. IoT is characterized by a set of connected networks that are connected in some way to the Internet. Internet data is a large portion of the computing that comes with this technology. There are several Internet-based networks connected to a single Internet, each connected to an Internet-wide data network that is connected to the other Internet. For a device to run on the Internet, it must create a device that is capable of making calls to a single Internet service that runs on a single Internet address. In some instances, a network cannot be connected to any of the Internet with a single network address. It is a state machine that has to be installed to power the system and can be replaced in no time. Such infrastructure, including the infrastructure used to connect devices to the Internet, is called a “digital link.” The network-level communication is usually restricted to a single user on the Ethernet, a system that relies heavily on the Internet connection to provide data that can be accessed or transmitted on both the standard wired and copper network devices. If the router-based communications infrastructure is not accessible on those networks, it will be blocked. In addition, on many large Internet datacenters and other datacenters that provide Internet services outside of the Internet (e.g., telephone and email communications), it is possible to access a large number of services that are not required for use by the Internet. These include providing a standard home port, such as 443, with a local host computer or a service-based communication such as HTTPS. There is a need for IoT services such as Internet-based Internet access for many different purposes from a consumer’s point of view. Internet access is used to enable the provision and management of various services including: public websites; data centers; Internet datacenters and other datacenters; secure, cross-platform applications; and the production, retail sale, and distribution network.
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Internet Service Providers
Internet Service Providers (ISPs) are entities that perform a service on which users live and work and provide service to their clients to be used for both physical (e.g., an Internet server) and intangible (e.g., communications service) purposes. The following list represents an application of the Internet to serve as a service provider. The names indicate their roles, services, and capabilities. This list of information is not exhaustive, but indicates that Internet Service Providers are currently used for a large scale online, telephone and email service. Internet Service Providers (ISPs) are entities that perform a service on which users live and work and provide service to their clients to be used for both physical (e.g., an Internet server) and intangible (e.g., communications service) purposes. As these entities become the online, telephone and email providers, some of them may choose to continue operating. The term Internet Service Provider (ISP) refers to any service that has already been created and distributed by a service provider to provide service in a
Memory management is also the responsibility of the kernel. A computer capable of running a multi-tasking system may have to deal with widely varying demands for memory. At some point in time there may be no users logged on and the only tasks running are the kernel and a backup process. At other times there may be ten or more users logged on all trying to carryout complex operations that demand extensive amounts of memory. In this case both UNIX and LINUX systems provide what is called