大连交通大学《云计算》-全部简答题.doc

1. how many types of scaling? What are they?Answer: 2 types,（1）Horizontal Scaling scaling out and scaling in,（2）Vertical Scaling scaling up and scaling down2. what are Cloud Characteristics? Answer: （1）on-demand usage（2）ubiquitous access（3）multitenancy (and resource pooling)（4）Elasticity（5）measured usage（6）Resiliency3.How many Cloud Delivery Models? What are they?Answer: 3 types,（1）Infrastructure-as-a-Service (IaaS)（2）Platform-as-a-Service (PaaS)（3）Software-as-a-Service (SaaS)1. Explains the difference between the concept of Multitenancy and Virtualization. With virtualization: Multiple virtual copies of the server environment can be hosted by a single physical server. With multitenancy: A physical or virtual server hosting an application is designed to allow usage by multiple different users. 2. What industry standards are represented the core technologies behind Web services?Web Service Description Language (WSDL)XML Schema Definition Language (XML Schema)SOAP Formerly known as the Simple Object Access ProtocolUniversal Description,Discovery,and Integration (UDDI)3.Describing the active and passive service agents.Active service agents perform an action upon intercepting and reading the contents of a message. The action typically requires making changes to the message contentsor changes to the message path itself. Passive service agents, do not change message contents. Instead, they read the message and may then capture certain parts of its contents, usually for monitoring, logging, or reporting purposes.4. Description the Modern data centers. Modern data centers exist as specialized IT infrastructure used to house centralized IT resources, such as servers, databases, networking and telecommunication devices, and software systems.5. What is calledserver consolidation?The coordination function that is provided by the virtualization software allows multiple virtual servers to be simultaneously created in the same virtualization host. Virtualization technology enables different virtual servers to share one physical server. This process is calledserver consolidation6. Which categories for Networked storage devices usually fall into?Storage Area Network (SAN)connected through a dedicated network provide block-level data storage accessusing industry standard protocolsNetwork-Attached Storage (NAS) Hard drive arrays are contained and managed by this dedicated device,connects through a network using file-centric data access protocols like the Network File System (NFS) or Server Message Block (SMB).6. Data centers require extensive network hardware in order to enable multiple levels of connectivity. the data center is broken down into five network subsystems,What is these ? Carrier and External Networks InterconnectionWeb-Tier Load Balancing and AccelerationLAN FabricSAN FabricNAS Gateways7. Three fundamental elements comprise the technology architecture of the Web, Which is these? Uniform Resource Locator (URL)Hypertext Transfer Protocol (HTTP)Markup Languages (HTML,XML)1. About the threat agents. ( 8 points )Questions:a) What is athreat agent？( 2 points )Answer: Athreat agentis an entity that poses a threat because it is capable of carrying out an attack.b) fill in the table. ( 6 points )threat agentDefintionAnanonymous attackeis a non-trusted cloud service consumer without permissions in the cloud.Amalicious service agentis able to intercept and forward the network traffic that flows within a cloud.Atrusted attackeshares IT resources in the same cloud environment as the cloud consumer and attempts to exploit legitimate credentials to target cloud providers and the cloud tenants with whom they share IT resourcesMalicious insidersare human threat agents acting on behalf of or in relation to the cloud provider.2. When does the following cloud security threat occur?( 8 points )a) Traffic eavesdropping b) Malicious intermediary threatc) Denial of service (DoS) attackd) Insufficient authorization attackAnswer:a) Traffic eavesdroppingoccurs when data being transferred to or within a cloud is passively intercepted by a malicious service agent for illegitimate information gathering purposes.b) Themalicious intermediarythreat arises when messages are intercepted and altered by a malicious service agent.c) The denial of service (DoS) attackoccurs when a targeted IT resource is overloaded to the point where they cannot function properly.d)The insufficient authorization attack occurs when access is granted to an attacker erroneously or too broadly, resulting in the attacker getting access to IT resources that are normally protected.1. About theready-made environment mechanism. Questions:a) What is the ready-made environmentmechanism？Answer: Theready-made environmentmechanism represents a pre-defined, cloud-based platform comprised of a set of already installed IT resources, ready to be used and customized by a cloud consumer. b) Which cloud delivery model is it a defining component? Answer:PaaS c) What do the cloud consumers utilize these environments to do? Answer:These environments are utilized by cloud consumers to remotely develop and deploy their own services and applications within a cloud. 2. About Cloud Usage Monitor. Questions:a) What is the Cloud Usage Monitor? Answer: Thecloud usage monitormechanism is a lightweight and autonomous software program responsible for collecting and processing IT resource usage data.b) please describe three common agent-based implementation formats. Answer:Amonitoring agentis an intermediary, event-driven program that exists as a service agent and resides along existing communication paths to transparently monitor and analyze dataflows Aresource agentis a processing module that collects usage data by having event-driven interactions with specialized resource software.Apolling agentis a processing module that collects cloud service usage data by polling IT resources.c) fill in the table. agent-based implementation format usagemonitoring agentbe used to measure network traffic and message metricsresource agentbe used to monitor usage metrics, such as initiating, suspending, resuming, and vertical scaling.polling agentbe used to periodically monitor IT resource status, such as uptime and downtime1、Beyond simple division of labor algorithms，load balancers can perform a range of specialized runtime workload distribution functions that include: （1） （2） （3） 2.In thepay-per-use monitormechanism，what are Some typical monitoring variables ？2、 What are the common resource cluster types ？4、What is the function of a failover system mechanism？How many configurations of failover system ?答案：1、（1）Asymmetric Distribution （2）Workload Prioritization （3）Content-Aware Distribution2、（1） request/response message quantity （2）transmitted data volume （3）bandwidth consumption3、 （1）Server Cluste （2）Database Cluster （3） Large Dataset Cluster4、Thefailover systemmechanism is used to increase the reliability and availability of IT resources by using established clustering technology to provide redundant implementations. two basic configurations:（1）Active-Active （2）Active-Passive1：Which management-related mechanisms are described in this book？答案：The resource management system mechanism The SLA management system mechanismThe remote administration system mechanism T he billing management system mechanism 1. What is the role of the Cloud Balancing Architecture?