Tencent Cloud Practitioner Certification Examination Examination Points—Basics of Cloud Computing

Cloud computing development history

1. What standards does Tencent Cloud Computer Room meet?

Tencent's computer room has reached the **T3+** standard
T3, whose full name is Uptime Tier 3. It is a foreign certification system. Uptime Tier certification
is the most recognized standard in the industry.

2. The difference between the two traditional IDC methods

Physical server hosting : Users purchase hardware by themselves and send it to the operator's computer room for hosting. During this period, the monitoring and management of the equipment are completed independently by the user. The IDC data center provides IP access, bandwidth access, power supply, network maintenance, etc. for
leasing : The IDC data center rents physical equipment to customers and is responsible for the stability of the environment. Users do not need to purchase hardware equipment.

3. Compared with traditional IDC, what are the advantages of cloud computing?

• Highly scalable and highly available computing capabilities
• Dynamic resource allocation, cloud computing can achieve horizontal/vertical elastic resource expansion and rapid scheduling
• Enterprises are completely freed from the management and operation of hardware equipment and focus on the development and innovation of internal business

*** 4. What are the characteristics of cloud computing?

Cloud computing characteristics	Feature description
Hyperscale	Public clouds often have tens of thousands or even millions of machines; private clouds also have at least hundreds or thousands of machines.
High availability	Multi-copy fault-tolerance mechanism provides high reliability of data
Elastic expansion	Provide dynamic elastic scaling functions to meet the needs of application and user scale growth
Multi-tenant isolation	Multiple different tenants share underlying hardware resources but are logically isolated in the upper layer
on demand services	Provides a huge resource pool that can be purchased on demand
Measurable monitoring resources	The cloud platform provides resource monitoring and metering functions
low cost	Users do not need to bear the high cost of data center management and can obtain effective resources at a lower cost.

Cloud computing technology architecture (two 3 two 4)

4 modes of cloud computing

model	Features	illustrate	Applicable scene
public cloud	Large scale, reliable operation and maintenance, and strong flexibility	The public cloud is built for the public. All users are called tenants. Not only are there many tenants at the same time, but also when a tenant leaves, its resources can be immediately released to the next tenant.	Games, videos, education, etc.
Private Cloud	Autonomous and controllable, good data privacy	A cloud in which the basic infrastructure is exclusive to a single organization. A private cloud can be managed by the organization itself or delegated to a third party.	Finance, medical, government affairs
hybrid cloud	Flexible, flexible but complex architecture	A hybrid cloud is any mix of the above. This mix can be computing, storage, or both. At this stage when public cloud is not yet fully mature, and private cloud is difficult to operate and maintain, requires long deployment times, and is difficult to dynamically expand, hybrid cloud is an ideal smooth transition method.	Finance, medical, etc.
Industry cloud	Strong professionalism and suitable for industries with high standards	A cloud suitable for the characteristics of a certain industry	every industry

What are the advantages and disadvantages of private cloud and hybrid cloud?

Private Cloud
Advantages: Supports customized and legacy applications; does not affect existing IT management processes
Disadvantages: High deployment costs; ongoing operating costs

Hybrid cloud
Advantages: Able to integrate the advantages of public cloud and private cloud; comprehensive architecture, flexible deployment; higher security
Disadvantages: complex architecture; higher cost than public cloud

3 service models of cloud computing

• IaaS (Infrastructure-as-a-Service): Infrastructure as a Service. Consumers can obtain services from complete computer
  infrastructure through the Internet. For example: rent a virtual machine.
• PaaS (Platform-as-a-Service): Platform as a Service. PaaS actually refers to using the software development platform as a service
  and submitting it to users in the SaaS model. Therefore, PaaS is also an application of the SaaS model. However, the emergence of PaaS
  can accelerate the development of SaaS, especially the development speed of SaaS applications. For example: personalized customized development of software.
• SaaS (Software-as-a-Service): software as a service. It is a model that provides software through the Internet. Users
  do not need to purchase software, but rent Web-based software from providers to manage business activities.

How do I determine which service applies?

Basic judgment : whether it is necessary to share hardware resources (IAAS), whether it is necessary to share operating platforms (paas), and whether different departments need unified applications (saas) to determine whether the enterprise environment requires cloud computing deployment.
From a service level perspective, choose IaaS, PaaS or SaaS platform according to the final enterprise product requirements.
From the perspective of demand demands , choose which cloud delivery model to use.
If you need to provide resource utilization, reduce energy consumption, and centralize automated management of resources, IaaS is needed to meet the needs.
If unified development and testing are required Or running platform, then you can choose to use PaaS.
If you need unified services, processes, models and experiences, then you need to choose to use SaaS to achieve it.

3 key technologies of cloud computing

1. Virtualization technology: computing virtualization, network virtualization, storage virtualization
2. Distributed data storage technology
3. Cloud computing management platform

Computing virtualization technology

Understanding of kvm?

KVM is a virtualization module embedded in the standard kernel of the Linux operating system. It can convert a Linux standard kernel into a VMM. The Linux standard kernel embedded with the KVM module can support GuestOS
loaded through kvm tools . KVM uses
To simulate the operation of the CPU, but lacks support for Network and I/O, QEMU-
KVM is a complete simulator, which is based on KVM and provides complete Network and I/O support.

What is the difference between kvm and xen?

kvm is a module of the Linux kernel, and xen is a Linux application.
Currently, both xen and kvm support virtualization and paravirtualization. Kvm requires the CPU to support virtualization, but xen can.
The I/O performance of kvm is relatively strong. xen is relatively old, and its later development is not as rapid as kvm.

Network virtualization technology

Network virtualization technology? CDN?

Software Defined Network (SDN) is a new innovative network architecture of Emulex Network and
an implementation method of network virtualization. Its core technology OpenFlow separates the control plane and data plane of network equipment
to achieve It provides flexible control of network traffic, making the network as a pipeline more intelligent.

Distributed data storage technology

Comparison between traditional data storage and distributed data storage?

traditional data storage

• Centralized storage of data
• Storage becomes the bottleneck of system performance and reliability
• Insufficient read and write computing performance, poor scalability, and low redundancy
• Unsatisfactory needs when the data scale is large. In scenarios where the amount of data is small and data expansion is limited, traditional storage devices can basically meet business needs with their own redundant designs and high-performance components. But it is not suitable for data storage in cloud computing scenarios.

Distributed data storage

• Run on multiple nodes, automatically integrated
• Integrate all storage space resources in the cluster, virtualize and provide external file access services
• Better scalability, larger capacity, and more suitable for performance requirements of large-scale data. Therefore, it often appears in cloud computing architecture

What are the advantages of distributed data storage?

Better scalability, larger capacity, more suitable for performance requirements of large-scale data
Integrate all storage space resources in the cluster, virtualize and provide external file access services
Run on multiple nodes, automatically integrated

Cloud computing management platform

What is the difference between openstack and vstation?

	OpenStack	VStation
Amount of code	tens of millions of rows	Hundreds of thousands of rows
Support cluster size	thousands of units	Hundreds of thousands of units
Disaster recovery	Requires support from other open source components	Any module can be deployed across computer rooms for disaster recovery
Operation and maintenance	Requires independent development	Message visualization
Personnel investment	hundreds of people	dozens of people
performance	Generally supports less than 100 simultaneous creations	Can support the creation of tens of thousands of virtual machines in minutes

4-layer architecture of cloud computing

1. infrastructure layer
2. Cloud platform layer
3. Business application layer
4. business management

The impact of cloud computing

What is the impact of cloud computing on organizations?

Reduce input costs,
save operating costs,
improve business and production levels, and
use resources flexibly and conveniently

What is the impact of cloud computing on products?

Generate new economic growth points.
Breakthroughs in key technology research and development.
Industry applications are extensive and in-depth, significantly driving industrial upgrading. The threshold
for innovation and entrepreneurship is significantly lowered
. Big data is closely integrated, and data services have become an important development direction for cloud computing companies.

Business mainstream cloud products

What are the advantages of different cloud vendors?

Vendor type	Advantage
Internet companies	Rich experience in IaaS services, strong technical research and development capabilities, and strong innovation capabilities
Telecom operators	Own bandwidth resources and rich data center resources
international firms	Started early, with cutting-edge technology and rich technical reserves. Due to geographical location and other factors, it is subject to certain competition in the domestic market.
Traditional IT companies	Rich communication operator service experience, technical research and development capabilities and strong sales service team
Other manufacturers	Relaxed and flexible environment, focusing on niche areas