1. CPU Virtualization
Virtualization in computing typically refers to the operation of computing elements on a virtual rather than a physical basis. Virtualization technology can expand hardware capacity and simplify the software reconfiguration process. In simple terms, CPU virtualization technology simulates multiple CPUs on a single CPU, allowing a platform to run multiple operating systems simultaneously, with applications running in independent spaces without affecting each other, thus significantly improving the efficiency of the computer’s operations.
Pure software virtualization solutions have many limitations. The “client” operating system often communicates with the hardware via a VMM (Virtual Machine Monitor), which decides its access to all virtual machines on the system. (Note that most processor and memory accesses are independent of the VMM and only involve the VMM when specific events occur, such as page faults.) In pure software virtualization solutions, the position of the VMM in the software suite is analogous to that of a traditional operating system. It interfaces with hardware components (such as processors, memory, storage, graphics cards, and network cards) to simulate a hardware environment. This conversion inevitably increases system complexity.
CPU virtualization technology is a hardware solution that supports virtualization technology. CPUs that support virtualization come with specially optimized instruction sets to control the virtualization process. With these instruction sets, the VMM can easily improve performance, which can significantly enhance performance compared to software virtualization implementations. Virtualization technology can provide chip-based functionality, improving pure software solutions with compatible VMM software. Since virtualization hardware can provide a completely new architecture that supports operating systems to run directly on it, binary translation is not needed, reducing the associated performance overhead and greatly simplifying VMM design, allowing the VMM to be written according to general standards, resulting in more powerful performance. Additionally, pure software VMMs currently lack support for 64-bit client operating systems, and as 64-bit processors become more prevalent, this serious drawback becomes increasingly prominent. CPU virtualization technology not only supports a wide range of traditional operating systems but also supports 64-bit client operating systems.
Virtualization technology is a set of solutions. The complete situation requires support from the CPU, motherboard chipset, BIOS, and software, such as VMM software or certain operating systems themselves. Even if only the CPU supports virtualization technology, in conjunction with VMM software, it will perform better than systems that do not support virtualization technology at all.
The two major CPU giants, Intel and AMD, have both sought to gain an edge in the virtualization field, but AMD’s virtualization technology lagged behind Intel’s by several months. Intel began promoting its Intel Virtualization Technology (Intel VT) in its processor product line at the end of 2005. Currently, Intel has released a series of processors with Intel VT virtualization technology, including desktop platforms like the Pentium 4 6X2 series, Pentium D 9X0 series, and Pentium EE 9XX series, as well as some products in the Core Duo and Core Solo series, and server/workstation platforms like the Xeon LV series, Xeon 5000 series, Xeon 5100 series, Xeon MP 7000 series, and Itanium 2 9000 series. Most of Intel’s next-generation mainstream processors, including Merom core mobile processors, Conroe core desktop processors, Woodcrest core server processors, and Itanium 2 high-end server processors based on the Montecito core, will support Intel VT virtualization technology.
On the AMD side, a series of processors that support AMD Virtualization Technology (AMD VT) have also been released, including the Socket S1 interface Turion 64 X2 series and the Socket AM2 interface Athlon 64 X2 and Athlon 64 FX series. Most of AMD’s next-generation mainstream processors, including the upcoming Socket F interface Opteron, will support AMD VT virtualization technology.
2. Network Virtualization
Network virtualization is currently one of the least defined and most controversial concepts in the industry regarding the subdivision of virtualization. In Microsoft’s view, “network virtualization” refers to virtual private networks (VPNs). VPNs abstract the concept of network connections, allowing remote users to access an organization’s internal network as if they were physically connected to it. Network virtualization can help protect the IT environment from threats from the Internet while allowing users to quickly and securely access applications and data.
However, networking giant Cisco does not see it that way. Having emerged, gained fame, and currently dominating the network space, Cisco naturally considers networking to be at the core of its vision for the future of IT. It believes that, theoretically, network virtualization can place any service-based traditional client/server model onto the “network.” This means that routers and switches can perform more services, naturally increasing Cisco’s importance and business revenue in the industry. Cisco states that network virtualization consists of three parts: access control, path extraction, and service advantages. From Cisco’s product roadmap, it can be seen that the company’s routers and switches will have features such as security, storage, VoIP, mobile services, and applications. For Cisco, their strategy is to generate continuous profits by expanding the sales of network infrastructure devices. For users, this can help them enhance the value of their network devices and adjust their existing network infrastructure.
For another giant in the networking camp, 3Com has made even larger moves in network virtualization than Cisco. 3Com’s routers can have a work card inserted into them. This card comes with a fully functional Linux server that can connect to the router’s core. In this Linux server, you can install applications such as sniffer, VoIP, and security applications. Additionally, the company plans to run VMware on the Linux card in the future, allowing users to run Windows Server. 3Com’s open-source network virtualization initiative is called 3Com ON (also known as Open Networking).
Of course, self-promotion by Cisco and 3Com cannot be considered a true sign of the rise of network virtualization. Currently, network virtualization is still in its early stages, but given the rapidly increasing demand for network informationization, we have reason to believe that its breakthroughs and growth will be swift.