Information Technology Reference
In-Depth Information
Here are some of the common benefits achieved through virtualization techniques:
Better use of computing resources, higher server densities, and simplified server
migrations
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Provides flexibility for ease of management for adds, reassignments, or repurposing
resources
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Separation of users groups on the same physical network, enabling traffic isolation
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Ability to provide per-department security policies
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Reduction in power and space required
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Increased uptime and reduced operational costs
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Ty p e s o f V i r t u a l i z a t i o n
Enterprise networks consist of two main types of virtualization technologies groupings,
called network virtualization and device virtualization:
Network virtualization
encompasses logical isolated network segments that share
the same physical infrastructure. Each segment operates independently and is logically
separate from the other segments. Each network segment appears with its own pri-
vacy, security, independent set of policies, QoS levels, and independent routing paths.
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Key
To p i c
Here are some examples of network virtualization technologies:
VLAN:
Virtual local-area network
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VSAN:
Virtual storage-area network
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VRF:
Virtual routing and forwarding
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VPN:
Virtual private network
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vPC:
Virtual Port Channel
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Device virtualization
allows for a single physical device to act like multiple copies of
itself. Device virtualization enables many logical devices to run independently of
each other on the same physical piece of hardware. The software creates virtual hard-
ware that can function just like the physical network device. Another form of device
virtualization entails using multiple physical devices to act as one logical unit.
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Here are some examples of device virtualization technologies:
Server virtualization: Virtual machines (VM)
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Cisco Application Control Engine (ACE) context
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Virtual Switching System (VSS)
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Cisco Adaptive Security Appliance (ASA) firewall context
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Virtual device contexts (VDC)
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