Talk:COMP 3000 Essay 1 2010 Question 1 - Revision history

Jslonosky: /* The Essay */

2010-10-15T02:50:10Z

The Essay

← Older revision		Revision as of 02:50, 15 October 2010
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	Made a few more edits to some of the wording. Looks good! --[[User:Aellebla\|Aellebla]] 01:52, 15 October 2010 (UTC)		Made a few more edits to some of the wording. Looks good! --[[User:Aellebla\|Aellebla]] 01:52, 15 October 2010 (UTC)



			- I wrote the conclusion and moved it into the answer space. Please take a look and make sure it is all formated properly. Got stuff to do. Thanks for all the awesome work guys/girls. Back to 3004! - JSlonosky

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Aellebla: /* The Essay */

2010-10-15T01:52:49Z

The Essay

← Older revision		Revision as of 01:52, 15 October 2010
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	Not only does the exokernel benefit from it's decreased task load but the library OSs also experience several benefits compared to operating on a microkernel or VM. Library OSs running on an exokernel have a reduction in the number of kernel crossings compared to a microkernel[1]. Since the library OS is not trusted by the exokernel it can then be trusted by the application. While a library OS may choose to handle low level management tasks it self, there is still a notion of portability for applications working with the library OSs. Applications that use a library OS that has implemented standard interfaces, such as POSIX, will be portable on any system with the same interface [1]. A library OS can also be made portable if it is designed to interact with a low-level, machine independent level to hide hardware details. [1]		Not only does the exokernel benefit from it's decreased task load but the library OSs also experience several benefits compared to operating on a microkernel or VM. Library OSs running on an exokernel have a reduction in the number of kernel crossings compared to a microkernel[1]. Since the library OS is not trusted by the exokernel it can then be trusted by the application. While a library OS may choose to handle low level management tasks it self, there is still a notion of portability for applications working with the library OSs. Applications that use a library OS that has implemented standard interfaces, such as POSIX, will be portable on any system with the same interface [1]. A library OS can also be made portable if it is designed to interact with a low-level, machine independent level to hide hardware details. [1]

	Exokernels follow the same design pattern of removing unnecessary code from within the kernel but without the same kernel to user space communication issues that microkernels experience. They also provide through their library OSs a simple yet effective way to emulate several different types of physical resource handling methods similar to virtual machines.		Exokernels follow the same design pattern of removing unnecessary code from within the kernel but without the same kernel to user space communication issues that microkernels experience. They also provide, through their library OSs, a simple yet effective way to emulate several different types of physical resource handling methods similar to virtual machines.

	Paragraph 4 - Contrast/Compromise --[[User:Asoknack\|Asoknack]] -- We may not need this. Corey did a good job with the Exokernel and incorporated the information and its compromise of the two systems		Paragraph 4 - Contrast/Compromise --[[User:Asoknack\|Asoknack]] -- We may not need this. Corey did a good job with the Exokernel and incorporated the information and its compromise of the two systems
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	Awesome Steph! Also, Awesome Corey, sounds sweet, looks good-JSlonosky		Awesome Steph! Also, Awesome Corey, sounds sweet, looks good-JSlonosky

			Made a few more edits to some of the wording. Looks good! --[[User:Aellebla\|Aellebla]] 01:52, 15 October 2010 (UTC)

	==Potential Test Questions==		==Potential Test Questions==

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Aellebla: /* The Essay */

2010-10-15T01:51:00Z

The Essay

← Older revision		Revision as of 01:51, 15 October 2010
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	Through these three functions the exokernel can control and allow many different situations. By tracking the ownership of the resources the exokernel can export privileged instructions to the library OS so that traditional OS abstractions can be implemented as well as allowing application based resource management which is the best way to build flexible and efficient systems all while avoiding resource management except when inter-library conflict protection is required to maintain system integrity.[1] By exposing the allocation and the raw resources and their physical names to the application layer the exokernel is able to allow the library to request physical resources which removes the expensive overhead that is involved with translating the virtual names to their physical names [3] also the physical names capture more useful information and are safer and less resource intensive. [3] Finally by exposing revocation the exokernel allows well behaved library OSs to preform application level resource management [1] and allows the library OS to choose what instance of the resource to release[1].		Through these three functions the exokernel can control and allow many different situations. By tracking the ownership of the resources the exokernel can export privileged instructions to the library OS so that traditional OS abstractions can be implemented as well as allowing application based resource management which is the best way to build flexible and efficient systems all while avoiding resource management except when inter-library conflict protection is required to maintain system integrity.[1] By exposing the allocation and the raw resources and their physical names to the application layer the exokernel is able to allow the library to request physical resources which removes the expensive overhead that is involved with translating the virtual names to their physical names [3] also the physical names capture more useful information and are safer and less resource intensive. [3] Finally by exposing revocation the exokernel allows well behaved library OSs to preform application level resource management [1] and allows the library OS to choose what instance of the resource to release[1].

	Not only does the exokernel benefit from it's decreased task load but the library OSs also experience several benefits compared to operating on a microkernel or VM. Library OSs running on an exokernel have a reduction in the number of kernel crossings compared to a microkernel[1] ~~also since~~ the library OS is not trusted by the exokernel it can then be trusted by the application. While a library OS may choose to handle low level management tasks it self, there is still a notion of portability for applications working with the library OSs ~~such that applications~~ that use a library OS that has ~~implement~~ standard interfaces, such as POSIX, will be portable on any system with the same interface [1] ~~and a~~ library OS can be made portable if it is designed to interact with a low-level machine independent level to hide hardware details. [1]		Not only does the exokernel benefit from it's decreased task load but the library OSs also experience several benefits compared to operating on a microkernel or VM. Library OSs running on an exokernel have a reduction in the number of kernel crossings compared to a microkernel[1]. Since the library OS is not trusted by the exokernel it can then be trusted by the application. While a library OS may choose to handle low level management tasks it self, there is still a notion of portability for applications working with the library OSs. Applications that use a library OS that has implemented standard interfaces, such as POSIX, will be portable on any system with the same interface [1]. A library OS can also be made portable if it is designed to interact with a low-level, machine independent level to hide hardware details. [1]

	Exokernels follow the same design pattern of removing unnecessary code from within the kernel but without the same kernel to user space communication issues that microkernels experience. They also provide through their library OSs a simple yet effective way to emulate several different types of physical resource handling methods similar to virtual machines.		Exokernels follow the same design pattern of removing unnecessary code from within the kernel but without the same kernel to user space communication issues that microkernels experience. They also provide through their library OSs a simple yet effective way to emulate several different types of physical resource handling methods similar to virtual machines.

Jslonosky: /* The Essay */

2010-10-14T23:43:32Z

The Essay

← Older revision		Revision as of 23:43, 14 October 2010
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	Exokernels follow the same design pattern of removing unnecessary code from within the kernel but without the same kernel to user space communication issues that microkernels experience. They also provide through their library OSs a simple yet effective way to emulate several different types of physical resource handling methods similar to virtual machines.		Exokernels follow the same design pattern of removing unnecessary code from within the kernel but without the same kernel to user space communication issues that microkernels experience. They also provide through their library OSs a simple yet effective way to emulate several different types of physical resource handling methods similar to virtual machines.

	Paragraph 4 - Contrast/Compromise --[[User:Asoknack\|Asoknack]]		Paragraph 4 - Contrast/Compromise --[[User:Asoknack\|Asoknack]] -- We may not need this. Corey did a good job with the Exokernel and incorporated the information and its compromise of the two systems

	Conclusion - Jon S. - Only a sentence per paragraph, excluding Intro		Conclusion - Jon S. - Only a sentence per paragraph, excluding Intro

Cling: /* The Essay */

2010-10-14T23:13:28Z

The Essay

← Older revision		Revision as of 23:13, 14 October 2010
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	Paragraph 3 -Exokernel -Corey L		Paragraph 3 -Exokernel -Corey L

	~~(This is only half, I have a Bell Tech here working on my internet. I will finish when he leaves)~~

	Exokernels can be seen as a compromise between a microkernel and a VM. It can also be seen as simply dividing a monolithic kernel up into 2 parts. The management tasks of the kernel remain in the exokernel, these are the raw resource management tasks such as memory management. While the higher level abstractions such as file systems, address spaces, and interprocess communication is done at the application level[1]. These abstractions are usually provided by library OSs which allow applications to handle their own machine resources in ways not possible with the traditional kernel. Which in turn can cause large performance boosts in several areas which will be shown below.		Exokernels can be seen as a compromise between a microkernel and a VM. It can also be seen as simply dividing a monolithic kernel up into 2 parts. The management tasks of the kernel remain in the exokernel, these are the raw resource management tasks such as memory management. While the higher level abstractions such as file systems, address spaces, and interprocess communication is done at the application level[1]. These abstractions are usually provided by library OSs which allow applications to handle their own machine resources in ways not possible with the traditional kernel. Which in turn can cause large performance boosts in several areas which will be shown below.
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	The exokernel walks this fine line between management and control by only providing three functions for accessing the machine's resources. It will only track ownership of resources, ensure protection by guarding all resource usage and bind points and revoke access to the resources. [1] By doing so the exokernel allows the library OSs maximum freedom over the machine's resources without allowing them to interfere with one another's resources as you would see in an unmanaged system.		The exokernel walks this fine line between management and control by only providing three functions for accessing the machine's resources. It will only track ownership of resources, ensure protection by guarding all resource usage and bind points and revoke access to the resources. [1] By doing so the exokernel allows the library OSs maximum freedom over the machine's resources without allowing them to interfere with one another's resources as you would see in an unmanaged system.

	Through these three functions the exokernel can control and allow many different situations. By tracking the ownership of the resources the exokernel can export privileged instructions to the library OS so that traditional OS abstractions can be implemented as well as allowing application based resource management which is the best way to build flexible and efficient systems all while avoiding resource management except when inter-library conflict protection is required to maintain system integrity.[1] By exposing the allocation and the raw resources and their physical names to the application layer the exokernel is able to allow ~~LibOs~~ to request physical resources		Through these three functions the exokernel can control and allow many different situations. By tracking the ownership of the resources the exokernel can export privileged instructions to the library OS so that traditional OS abstractions can be implemented as well as allowing application based resource management which is the best way to build flexible and efficient systems all while avoiding resource management except when inter-library conflict protection is required to maintain system integrity.[1] By exposing the allocation and the raw resources and their physical names to the application layer the exokernel is able to allow the library to request physical resources which removes the expensive overhead that is involved with translating the virtual names to their physical names [3] also the physical names capture more useful information and are safer and less resource intensive. [3] Finally by exposing revocation the exokernel allows well behaved library OSs to preform application level resource management [1] and allows the library OS to choose what instance of the resource to release[1].


			Not only does the exokernel benefit from it's decreased task load but the library OSs also experience several benefits compared to operating on a microkernel or VM. Library OSs running on an exokernel have a reduction in the number of kernel crossings compared to a microkernel[1] also since the library OS is not trusted by the exokernel it can then be trusted by the application. While a library OS may choose to handle low level management tasks it self, there is still a notion of portability for applications working with the library OSs such that applications that use a library OS that has implement standard interfaces, such as POSIX, will be portable on any system with the same interface [1] and a library OS can be made portable if it is designed to interact with a low-level machine independent level to hide hardware details. [1]

			Exokernels follow the same design pattern of removing unnecessary code from within the kernel but without the same kernel to user space communication issues that microkernels experience. They also provide through their library OSs a simple yet effective way to emulate several different types of physical resource handling methods similar to virtual machines.

	Paragraph 4 - Contrast/Compromise --[[User:Asoknack\|Asoknack]]		Paragraph 4 - Contrast/Compromise --[[User:Asoknack\|Asoknack]]

Jslonosky: /* The Essay */

2010-10-14T22:54:24Z

The Essay

← Older revision		Revision as of 22:54, 14 October 2010
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	So far so good, if you find some sentences that are off, go ahead and correct them, just note to us in here that you've made changes. Almost done guys! -Slade		So far so good, if you find some sentences that are off, go ahead and correct them, just note to us in here that you've made changes. Almost done guys! -Slade

	Awesome Steph! -JSlonosky		Awesome Steph! Also, Awesome Corey, sounds sweet, looks good-JSlonosky

	==Potential Test Questions==		==Potential Test Questions==

	Add potential test questions here:		Add potential test questions here:

Cling: /* The Essay */

2010-10-14T22:37:24Z

The Essay

← Older revision		Revision as of 22:37, 14 October 2010
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	Paragraph 3 -Exokernel -Corey L		Paragraph 3 -Exokernel -Corey L

			(This is only half, I have a Bell Tech here working on my internet. I will finish when he leaves)

			Exokernels can be seen as a compromise between a microkernel and a VM. It can also be seen as simply dividing a monolithic kernel up into 2 parts. The management tasks of the kernel remain in the exokernel, these are the raw resource management tasks such as memory management. While the higher level abstractions such as file systems, address spaces, and interprocess communication is done at the application level[1]. These abstractions are usually provided by library OSs which allow applications to handle their own machine resources in ways not possible with the traditional kernel. Which in turn can cause large performance boosts in several areas which will be shown below.

			The exokernel walks this fine line between management and control by only providing three functions for accessing the machine's resources. It will only track ownership of resources, ensure protection by guarding all resource usage and bind points and revoke access to the resources. [1] By doing so the exokernel allows the library OSs maximum freedom over the machine's resources without allowing them to interfere with one another's resources as you would see in an unmanaged system.

			Through these three functions the exokernel can control and allow many different situations. By tracking the ownership of the resources the exokernel can export privileged instructions to the library OS so that traditional OS abstractions can be implemented as well as allowing application based resource management which is the best way to build flexible and efficient systems all while avoiding resource management except when inter-library conflict protection is required to maintain system integrity.[1] By exposing the allocation and the raw resources and their physical names to the application layer the exokernel is able to allow LibOs to request physical resources




	Paragraph 4 - Contrast/Compromise --[[User:Asoknack\|Asoknack]]		Paragraph 4 - Contrast/Compromise --[[User:Asoknack\|Asoknack]]

Jslonosky: /* The Essay */

2010-10-14T20:45:33Z

The Essay

← Older revision		Revision as of 20:45, 14 October 2010
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	So far so good, if you find some sentences that are off, go ahead and correct them, just note to us in here that you've made changes. Almost done guys! -Slade		So far so good, if you find some sentences that are off, go ahead and correct them, just note to us in here that you've made changes. Almost done guys! -Slade

			Awesome Steph! -JSlonosky

	==Potential Test Questions==		==Potential Test Questions==

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Aellebla: /* The Essay */

2010-10-14T20:05:37Z

The Essay

← Older revision		Revision as of 20:05, 14 October 2010
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	There are various ways of implementing hardware virtualization in a system to allow VMs to run. This includes device emulation, paravirtualization and dedicated devices. [9]		There are various ways of implementing hardware virtualization in a system to allow VMs to run. This includes device emulation, paravirtualization and dedicated devices. [9]

	In device emulation, the VMM provides a complete virtualization of a device for the guestOS to interact with, in software. [9] The VMM will map this virtualized device to the physical resource and handle any interactions between them. This will usually include converting instructions from the guestOS into instructions that are compatible with the device. [9] Device emulation allows for the VM to be migrated easily to another machine as it is not dependent on the physical devices but on the software emulations instead. [9] It also allows for simpler multiplexing between multiple virtual machines as it can handle sharing though these virtualized devices. [9] A drawback of emulation, however, is poor performance as the VMM must handle every request and convert them to be compatible with the physical device. [9] ~~However~~, despite its poor performance, emulation is the most common form of virtualization.		In device emulation the VMM provides a complete virtualization of a device for the guestOS to interact with, in the software. [9] The VMM will map this virtualized device to the physical resource and handle any interactions between them. This will usually include converting instructions from the guestOS into instructions that are compatible with the device. [9] Device emulation allows for the VM to be migrated easily to another machine as it is not dependent on the physical devices but rather, on the software emulations instead. [9] It also allows for simpler multiplexing between multiple virtual machines as it can handle sharing though these virtualized devices. [9] A drawback of emulation, however, is poor performance. This is because the VMM must handle every request and convert them to be compatible with the physical device. [9] Nonetheless, despite its poor performance, emulation is still the most common form of virtualization.

	Paravirtualization allows for a boost in performance by having the guestOS and the hostOS work together to improve performance. [9] In paravirtualization, the guestOS is not a native OS and must be modified so ~~that it~~ is aware that it is a virtualized system. [9] As the guestOS is aware of this, it can now make better decisions about how it accesses devices. As the guestOS will be able to handle its decisions better, the VMM’s responsibility is reduced as it now does not have to translate between the guestOS and the physical devices. [9] Though the performance boost is a great advantage, there are many disadvantages to this. ~~You~~ can only use paravirtualization if you can implement the modifications to the guestOS. ~~Not~~ everything can be paravirtualized and as such, this limits the cases in which this method can be used. [9] Also, every guestOS must be modified in order to be used in paravirtualization. The modifications will differ in various OS and so, there is also the task of implementing these changes to make a guestOS compatible. [9]		Paravirtualization allows for a boost in performance by having the guestOS and the hostOS work together to improve performance. [9] In paravirtualization, the guestOS is not a native OS and must be modified so guestOS is aware that it is a virtualized system. [9] Since the guestOS is aware of this, it can now make better decisions about how it accesses devices. Seeing as the guestOS will be able to handle its decisions better, the VMM’s responsibility is reduced as it now does not have to translate between the guestOS and the physical devices. [9] Though the performance boost is a great advantage, there are many disadvantages to this. Some disadvantages are that you can only use paravirtualization if you can implement the modifications to the guestOS. As well, not everything can be paravirtualized and as such, this limits the cases in which this method can be used. [9] Also, every guestOS must be modified in order to be used in paravirtualization. The modifications will differ in various OS and so, there is also the task of implementing these changes to make a guestOS compatible. [9]

	Instead of virtualizing the hardware and mediating between ~~with~~ the VMM, dedicated devices allow mapping directly to the guestOS. [9] In this method, the device will use the guestOS’s drivers instead of the hostOS’s. [9] Using this method allows the guestOS to use the hardware to its full extent without having to deal with the VMM. This simplifies the VMM by eliminating the overhead in virtualizating the hardware and handling the requests to devices. [9] However, there are limited physical resources to be dedicated to a guestOS ~~and this~~ also makes migration difficult as the guestOS is dependent on the physical device. [9]		Instead of virtualizing the hardware and mediating between the VMM, dedicated devices allow mapping directly to the guestOS. [9] In this method, the device will use the guestOS’s drivers instead of the hostOS’s. [9] Using this method allows the guestOS to use the hardware to its full extent, without having to deal with the VMM. This then, simplifies the VMM by eliminating the overhead by virtualizating the hardware and handling the requests to devices. [9] However, there are limited physical resources to be dedicated to a guestOS. This also makes migration difficult as the guestOS is dependent on the physical device. [9]

	'''notes'''		'''notes'''

Aellebla: /* The Essay */

2010-10-14T19:42:01Z

The Essay

← Older revision		Revision as of 19:42, 14 October 2010
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	A kernel is the lowest level section of an operating system. Within a system, it has the most privileges. It runs along side of the ‘user space’. It is in the ‘user space’ where a user has access. This is also where the user can run its applications and libraries.[8] This leaves the kernel with the need to manage the other necessary processes. For example, the kernel could manage the File Systems and complete process scheduling. The kernel is layered with the most authoritative process on its lowest level.[8] A monolithic kernel, which is a kernel that contains all mandatory processes within itself, was the common kernel type of the earlier versions of today’s operating systems utilized. However, this architecture had problems. [8] If the kernel needed to be updated with more code, or a change in the system, the entire kernel would need to be compiled. Therefore, due to the amount of processes within it, it would take an inefficient amount of time. Here, a microkernel becomes practical.		A kernel is the lowest level section of an operating system. Within a system, it has the most privileges. It runs along side of the ‘user space’. It is in the ‘user space’ where a user has access. This is also where the user can run its applications and libraries.[8] This leaves the kernel with the need to manage the other necessary processes. For example, the kernel could manage the File Systems and complete process scheduling. The kernel is layered with the most authoritative process on its lowest level.[8] A monolithic kernel, which is a kernel that contains all mandatory processes within itself, was the common kernel type of the earlier versions of today’s operating systems utilized. However, this architecture had problems. [8] If the kernel needed to be updated with more code, or a change in the system, the entire kernel would need to be compiled. Therefore, due to the amount of processes within it, it would take an inefficient amount of time. Here, a microkernel becomes practical.

	The concept of a microkernel, is to reduce the code within the kernel. The microkernel is only included in the kernel if it would impact the system. There are a variety of ways the system could be affected if a microkernel were to be implemented, for example, there would be increased performance and efficiency. [7] So, a microkernel is a kernel that has a reduced amount of mandatory software within itself. This means that it contains less software ~~that it has~~ to manage, and has a reduced size. A microkernel that emerged at the end of the 1980’s to the early 1990’s has the structure that processes ~~like~~ the File Systems and the Drivers are removed from it, leaving the kernel with process control and input/out control, and interrupts. [8] This new structure makes the system much more modular, and easier to provide solutions. If a driver must be patched or upgraded, the kernel does not need to be recompiled. [7] The old driver can be removed, and ~~while~~ the device waits for the system to recognize it, the operating system replaces the driver. This ~~lets~~ real-time updating, ~~and it~~ can be done while the computer is still functional. This can reduce the complete crash of the system. If a device fails, the kernel will not crash itself, like a monolithic kernel would. The microkernel can reload the driver of the device that failed and continue functioning. [7]		The concept of a microkernel, is to reduce the code within the kernel. The microkernel is only included in the kernel if it would impact the system. There are a variety of ways the system could be affected if a microkernel were to be implemented, for example, there would be increased performance and efficiency. [7] Furthermore, a microkernel is a kernel that has a reduced amount of mandatory software within itself. This means that it contains less software to manage, and has a reduced size.

			A microkernel that emerged at the end of the 1980’s to the early 1990’s has the structure that processes as if the File Systems and the Drivers are removed from it, leaving the kernel with process control and input/out control, and interrupts. [8] This new structure makes the system much more modular, and easier to provide solutions. If a driver must be patched or upgraded, the kernel does not need to be recompiled. [7] The old driver can be removed, and during the time the device waits for the system to recognize it, the operating system replaces the driver. This allows for real-time updating, that can be done while the computer is still functional. This can reduce the complete crash of the system. Therefore,if a device fails, the kernel will not crash itself, like a monolithic kernel would. The microkernel can reload the driver of the device that failed and continue functioning. [7]

	Want more on the scheduling? I can do that if wanted. -key note on exokernel's mutiplexing vs microkernel's messaging, exo more efficient so perhaps running with the idea that messaging b/w processes not necessarily the ideal way need to also start outlaying weaknesses in the design as well in order to play up the idea that an exokernel just does it better -Slade		Want more on the scheduling? I can do that if wanted. -key note on exokernel's mutiplexing vs microkernel's messaging, exo more efficient so perhaps running with the idea that messaging b/w processes not necessarily the ideal way need to also start outlaying weaknesses in the design as well in order to play up the idea that an exokernel just does it better -Slade
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	Paragraph 2 -Virtual Machine -Steph L.		Paragraph 2 -Virtual Machine -Steph L.

	A Virtual Machine, or VM, is a software abstraction of a physical machine. This entails virtualization of the physical machines resources in order to share them among OS run in the VM. Virtualizing these resources allow the OS to run as if it were on a full machine when, in reality, it is actually running in a virtualized environment on top of a hostOS~~, the~~ OS actually running on the machine, sharing the resources.		A Virtual Machine, or VM, is a software abstraction of a physical machine. This entails virtualization of the physical machines resources in order to share them among OS run in the VM. Virtualizing these resources allow the OS to run as if it were on a full machine when, in reality, it is actually running in a virtualized environment on top of a hostOS. The OS is actually running on the machine, sharing the resources.

	Virtual Machines generally contain two key components, the Virtual Machine Monitor, or VMM and the VM.		Virtual Machines generally contain two key components; both the Virtual Machine Monitor, or VMM and the VM.

	The VMM, also known as the hypervisor, manages the virtualization of the physical resources and the interactions with the VM running on top. [4] In other words, it mediates between the virtualized world and the physical world, keeping them separate and monitoring their interactions with each other. The hypervisor is what allows the VM to operate as if it were on its own machine by handling any requests to resources and maintaining these requests with what has actually been provided to the VM by the hostOS. The hostOS provides management for the VMM as well as allowing physical access to devices, hardware and drivers. [6]		The VMM, also known as the hypervisor, manages the virtualization of the physical resources and the interactions with the VM running on top. [4] In other words, it mediates between the virtualized world and the physical world, keeping them separate and monitoring their interactions with each other. The hypervisor is what allows the VM to operate as if it were on its' own machine. This is done by handling any requests to resources and maintaining these requests with what has actually been provided to the VM, by the hostOS. The hostOS provides management for the VMM, as well as, allowing physical access to devices, hardware and drivers. [6]

	The VM is what contains the OS we are running through virtualization. [6] This OS is called the guestOS ~~and it~~ will only be able to access any resources that have been made available to the VM by the hostOS. [6] Otherwise, the guestOS will not know about any other resources and does not have direct access to physical hardware. This will be taken care of by the VMM ~~but~~ the guestOS will execute as its own machine, unaware of this mediator.		The VM, is what contains the OS, we are running through virtualization. [6] This OS is called the guestOS. It will only be able to access any resources that have been made available to the VM by the hostOS. [6] Otherwise, the guestOS will not know about any other resources and does not have direct access to physical hardware. This will be taken care of by the VMM. While, the guestOS will execute as its own machine, unaware of this mediator.

	There are various ways of implementing hardware virtualization in a system to allow VMs to run. This includes device emulation, paravirtualization and dedicated devices. [9]		There are various ways of implementing hardware virtualization in a system to allow VMs to run. This includes device emulation, paravirtualization and dedicated devices. [9]