Podcast Beta
Questions and Answers
What characterizes a private cloud?
Which of the following is an example of a private cloud service?
What is a common misconception about private clouds?
In which scenario is a private cloud considered on-site?
Signup and view all the answers
What is a key requirement for organizations using an on-site private cloud?
Signup and view all the answers
What is a primary concern for organizations considering the use of an on-site private cloud?
Signup and view all the answers
What does the security perimeter of an on-site private cloud signify?
Signup and view all the answers
Which of the following best describes outsourced private clouds?
Signup and view all the answers
What is a potential risk of workloads residing concurrently on the same systems in an on-site private cloud?
Signup and view all the answers
What impacts the on-demand bulk data import/export capabilities in an on-site private cloud?
Signup and view all the answers
What is a significant financial consideration when migrating to an on-site private cloud?
Signup and view all the answers
Which aspect of an on-site private cloud is dependent on anticipated workloads?
Signup and view all the answers
What allows a subscriber to enhance security against external threats in an on-site private cloud?
Signup and view all the answers
What feature distinguishes an outsourced private cloud from an on-site private cloud?
Signup and view all the answers
Why might real-time processing be problematic in an on-site private cloud?
Signup and view all the answers
Which statement is true regarding client workload security in an on-site private cloud?
Signup and view all the answers
What primarily influences the security of data in an outsourced private cloud?
Signup and view all the answers
Which of the following is a key risk associated with multi-tenancy in an outsourced private cloud?
Signup and view all the answers
What is a potential limitation when conducting bulk data import/export in an outsourced private cloud?
Signup and view all the answers
What main costs might a subscriber incur when migrating to an outsourced private cloud?
Signup and view all the answers
How can communication limitations in an outsourced private cloud scenario be addressed?
Signup and view all the answers
In what way does the security perimeter differ in an outsourced private cloud compared to an on-site private cloud?
Signup and view all the answers
What capability do providers have that is a core advantage for outsourced private cloud services?
Signup and view all the answers
Which factor may necessitate an upgrade of the subscriber's network when moving to an outsourced private cloud?
Signup and view all the answers
What happens when the parser encounters an external entity that it cannot retrieve?
Signup and view all the answers
Which type of XML parser must retrieve all defined entities in the DTD?
Signup and view all the answers
How does a non-validating parser handle unresolved external entities?
Signup and view all the answers
What is the role of entity references in XML processing?
Signup and view all the answers
Which character is specified as not usable as whitespace in XML tags?
Signup and view all the answers
What should be used to include characters not defined in the encoding charset in XML?
Signup and view all the answers
What is a special characteristic of validating parsers in XML processing?
Signup and view all the answers
What occurs if an XML parser identifies an external entity?
Signup and view all the answers
What distinguishes control sensitive instructions from behavior sensitive instructions?
Signup and view all the answers
What is required for a VMM to be constructed on a conventional third generation computer?
Signup and view all the answers
What characterizes full virtualization in server environments?
Signup and view all the answers
What is a significant drawback of using full virtualization?
Signup and view all the answers
What is the primary way the guest operating system interacts with the VMM in para-virtualization?
Signup and view all the answers
What does hardware-assisted virtualization primarily allow?
Signup and view all the answers
Which of the following represents a modification approach in para-virtualization?
Signup and view all the answers
What is one of the notable features of QEMU and Bochs in virtualization?
Signup and view all the answers
Which of the following describes a main advantage of hardware-assisted virtualization?
Signup and view all the answers
Which of the following accurately describes a limitation of using para-virtualization?
Signup and view all the answers
What is a common misconception regarding virtual machine portability?
Signup and view all the answers
Why might a guest OS benefit from para-virtualized drivers?
Signup and view all the answers
What is the role of the VMM in a hardware-assisted virtualization environment?
Signup and view all the answers
Study Notes
Public Cloud
- Restrictive default service level agreements
- Public cloud service level agreements set limitations on how the cloud resources can be used.
Private Cloud
- Infrastructure is exclusive to a single organization
- Multiple consumers within the organization can access the resources
- Examples include:
- Eucalyptus
- Ubuntu Enterprise Cloud - UEC
- Amazon VPC
- VMware Cloud Infrastructure Suite
- Microsoft ECI data center.
- Private cloud can be managed by a third party and exist off-premises
- Two main scenarios exist:
- On-site Private Cloud: implemented at the customer's location
- Outsourced Private Cloud: server-side is managed by a hosting company.
On-site Private Cloud
- Subscriber organization retains control over resources within the security perimeter
- Factors to consider:
- Subscribers still need IT skills to manage the environment
- Workload location is hidden from clients for better resource management
- Client workloads can reside concurrently within the same infrastructure, requiring strong access control policies
- Network dependency impacts bulk data transfer and real-time processing
- Secure from external threats with proper security perimeter implementation
- Significant upfront costs for migrating to the cloud
Outsourced Private Cloud
- Two security perimeters are involved: one implemented by the subscriber and one by the provider.
- Stronger protection depends on both security perimeters and the protected communication link
- Considerations include:
- Subscribers may be able to provision unique communication links with the provider.
- Risks related to multi-tenancy are similar to on-site private clouds.
- Network capacity limitations impact data transfer and real-time processing
- Robust security measures are needed at both subscriber and provider perimeters.
- Moderate to significant upfront costs for migration
- Core competencies of providers: provisioning and operating computing equipment at scale
- Main start-up costs are negotiation of service level agreements, network upgrades, application porting to the cloud, and training.
Virtualization
- Virtual Machine Monitor (VMM) can be constructed if sensitive instructions of a computer are a subset of privileged instructions.
- A computer is recursively virtualizable if a VMM without timing dependencies can be built.
VMM & VM
- VMMs are the core of virtualization technology.
- VMMs are responsible for managing and isolating VMs for security and performance considerations.
Server Virtualization Approaches
- Full Virtualization
- First generation approach for x86/x64 server virtualization
- Uses dynamic binary translation to emulate system hardware and software
- Emulation layer talks to an operating system
- Guest OS does not perceive the emulated environment
- Para-Virtualization
- Guest OS is modified to run kernel-level operations
- Guest OS is aware of privileged instructions
- VMM handles virtualization
- Guest OS communicates with the VMM via a specialized API
- Guest OS is modified to run kernel-level operations
- Hardware-assisted virtualization
- Guest OS runs in ring 0
- VMM emulates privileged operations by using processor extensions
- Removes many complexities of VMM development
- VMM runs in a privileged ring higher than 0
Network Virtualization
- Virtualization of network infrastructure, such as:
- Switches
- Routers
- Firewalls
- Load balancers
- Allows for greater flexibility and efficiency in managing network resources
Why Virtualize?
- Allows for greater utilization of computing resources
- Improves flexibility and scalability of infrastructure
- Provides isolation and security to enhance reliability
XML Processing Rules: External Entities
- External entities are referenced in a DTD to import external data into an XML document.
- XML parsers can be validating or non-validating.
- Validating parsers must retrieve all entities and verify compatibility with DTD rules.
- Non-validating parsers attempt to retrieve entities but cease processing the DTD at the first unresolved entity.
Special Issues: Characters and Charsets
- XML defines specific characters as whitespace in tags.
- EBCIDIC character 'NEL' cannot be used as whitespace.
- Character references can be used to include characters not defined in the current encoding charset.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
This quiz explores the differences between public and private cloud infrastructures, including their service level agreements and examples of private cloud solutions. It covers various scenarios, such as on-site and outsourced private clouds, providing insights into management and organizational control.