Parallels Workstation

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Parallels Workstation

A screenshot of Parallels Desktop 2.1 running on Mac OS X, from Parallels' site
Developer:	Parallels, Inc.
Latest release:	2.2 /
OS:	Mac OS X, Microsoft Windows, Linux
Platform:	Wintel, Lintel, Macintel
Use:	Virtual machine
License:	Proprietary
Website:	Parallels Workstation

Parallels Workstation is the first commercial software product released by Parallels, Inc., a developer of desktop and server virtualization software. The Workstation software consists of a virtual machine suite for Intel x86-compatible computers (running Microsoft Windows, Linux or Mac OS X) which allows the simultaneous creation and execution of multiple x86 virtual computers. The product is distributed as a download package for Linux and Windows.

On the Mac, the software is branded Parallels Desktop for Mac (see below).

1 Implementation
2 Functionalities
3 Trivia
4 Issues
5 See also
- 5.1 General articles
- 5.2 Articles on specific related products
6 External links
7 References

[edit] Implementation

Like other virtualization software, Parallels Workstation uses hypervisor technology, which is a thin software layer between Primary OS and host computer. The hypervisor directly controls some of the host machine's hardware resources and provides an interface to it for both virtual machine monitors and primary OS. This allows virtualization software to reduce overhead. Parallels Workstation's hypervisor also supports hardware virtualization technologies like Intel Virtualization Technology ("VT") and AMD SVM (Secure Virtual Machine).

[edit] Functionalities

Parallels Workstation is a hardware emulation virtualization software, in which a virtual machine engine enables each virtual machine to work with its own processor, RAM, floppy drive, CD drive, I/O devices, and hard disk – everything a physical computer contains. Parallels Workstation virtualizes all devices within the virtual environment, including the video adapter, network adapter, and hard disk adapters. It also provides pass-through drivers for parallel port and USB devices.

Because all guest virtual machines use the same hardware drivers irrespective of the actual hardware on the host computer, virtual machine instances are highly portable between computers. For example, a running virtual machine can be stopped, copied to another physical computer, and restarted.

Parallels Workstation is able to virtualize a full set of standard PC hardware, including:

A Pentium or AMD Duron processor
A generic motherboard compatible with Intel i815 chipset
Up to 1.5GB of RAM (even though the real i815 only supports 512 MB)
VGA and SVGA video cards with VESA 3.0 support
A 1.44 MB floppy drive, which can be mapped to a physical drive or to an image file.
Up to four IDE devices. This includes virtual hard drives that range in size from 20 MB to 128 GB each and CD/DVD-ROM drives. IDE devices can be mapped to physical drive or to an image file.
Up to four serial ports that can be mapped to a real port, to a pipe or to an output file.
Up to three bi-directional parallel ports, each of which can be mapped to a real port, to a real printer or to an output file.
An Ethernet virtual network card compatible with Realtek RTL8029(AS).
2-port USB 1.1 controller.
An AC97 compatible sound card.
A 104-key Windows enhanced keyboard and a PS/2 wheel mouse.

[edit] Trivia

Initially, the software was released for the Mac as “Parallels Workstation for Mac OS X,” consistent with the Linux and Windows versions.^[1] This was not well received within the Mac community, where some felt that the name, particularly the term “workstation,” evoked the aesthetics of a Windows product.^[1] Parallels agreed: “[S]ince we've got a great Mac product, we should make it look and sound like a Mac product... the result is ‘Parallels Desktop for Mac’. We're really pleased with the new name, and we hope that you are, too.”^[1]

Except for the name, the Mac version is functionally identical to current Linux and Windows versions. In the latest released betas of Parallels Desktop for Mac, however, a new feature known as Coherence has been added, which basically removes Windows chrome, desktop, and the virtualization frame, creating a more seamless environment between Windows and OS X applications. In addition, a shared clipboard and drag-drop support between the host and guest OS have been implemented. Finally, the newest beta can boot existing Boot Camp partitions if a utility application is installed in the Boot Camp instance of Windows.

[edit] Issues

Currently Parallels can only run on 32 bit Primary OSes. DVD/CD-ROM "pass-through" access has not been implemented, which means that it is impossible to use DVD and CD burners exclusively in guest virtual machines. The product does not include an out-of-the-box Physical to Virtual (P2V) migration utility. Supported memory limit for all virtual machines is 4 GB, and memory limit for a single virtual machine is 1500 MB. In practical terms, Parallels has not yet fulfilled its promises of full USB 1.1 and iSight support, hampering many users' experience of the software. Devices like USB mice, memory keys, webcams and cellular phones are frequently cited on the company's support forum linkThe support team has promised to fix some of these issues, but has not indicated when users can expect a fix.