Cloud Computing Concept, Technology & Architecture

Transcription

Cloud ComputingConcept, Technology & ArchitectureChapter 05Cloud-Enabling Technology課 程 名 稱: 雲 端 管理 系 統授 課 教 師: 高 勝 助

Contents2 Contemporary technologies that realize modern-day cloud computing platforms and innovationsare discussed, particularly data centers,virtualization, and Web-based technologies. 5.1 Broadband Networks and Internet Architecture5.2 Data Center Technology5.3 Virtualization Technology5.4 Web Technology5.5 Multitenant Technology5.6 Service Technology5.7 Case Study Example

5.1 Broadband Networks and Internet Architecture3 Internet Service Providers (ISPs) (Figure 5.1 & 5.2) Connectionless Packet Switching (Datagram Networks) Router-Based Interconnectivity (Figure 5.3 & 5.4) Technical and Business Considerations (Figure 5.5 &5.6) Connectivity issuesNetwork bandwidth and latency issuesCloud carrier and cloud provider selection

Figure 5.14 Figure 5.1 - Twomessages travel overdynamic network routesin this ISPinternetworkingconfiguration.

Figure 5.25 Figure 5.2 - Anabstraction of theinternetworking structureof the Internet.

Figure 5.36 Figure 5.3 - Packetstraveling through theInternet are directedby a router thatarranges them into amessage.

Figure 5.47 Figure 5.4 - A generic view of the Internet reference model andprotocol stack.

Figure 5.58 Figure 5.5 - The internetworking architecture of a private cloud. Thephysical IT resources that constitute the cloud are located and managedwithin the organization.

Figure 5.69 Figure 5.6 - Theinternetworkingarchitecture of anInternet-based cloudcomputingdeployment model.The Internet is theconnecting agentbetween nonproximate cloudconsumers, roamingend-users, and thecloud provider'snetwork.

A comparison of on-premise and cloud-basedinternetworking10On-Premise IT ResourcesCloud-Based IT Resourcesinternal end-user devices accesscorporate IT services through thecorporate networkinternal end-user devices accesscorporate IT services through anInternet connectioninternal users access corporate ITservices through the corporate Internetconnection while roaming in externalnetworksinternal users access corporate ITservices while roaming in externalnetworks through the cloud provider’sInternet connectionexternal users access corporate ITservices through the corporateInternet connectionexternal users access corporate ITservices through the cloud provider’sInternet connection

Summary of Broadband Networks and Internet11 Cloud consumers and cloud providers typically usethe Internet to communicate, which is based on adecentralized provisioning and management modeland is not controlled by any centralized entities. The main components of internetworkingarchitecture are connectionless packet switching androuter-based interconnectivity, which use networkrouters and switches. Networks bandwidth and latency are characteristicsthat influences QoS, which is heavily impacted bynetwork congestion.

5.2 Data Center Technology (1/2)12 Grouping IT resources in close proximity with oneanother allows for power saving, higher efficiency insharing resources, and improve accessibility for ITpersonnel. Following issues are concerned:1. Virtualization (Figure 5.7)2. Standardization and Modularity (enable economy of scale)3. Automation (self-configuration, recovery)4. Remote Operation and Management5. High Availability (through redundancy)

5.2 Data Center Technology (2/2)136. Security-Aware Design, Operation, andManagement (outsourcing resources)7. Facilities (power, cabling, cooling, fire protection, )8. Computing Hardware (standardized commodity servers)9. Storage Hardware (array, hot-swapping, storagevirtualization, fast data replication, SAN, NAS, )10. Network Hardware1)2)3)4)5)Carrier and External Networks InterconnectionWeb-Tier Load Balancing and AccelerationLAN FabricANS FabricNAS Gateways

Figure 5.714 Figure 5.7 - The commoncomponents of a datacenter working togetherto provide virtualized ITresources supported byphysical IT resources.

Summary Data Center Technology (1/2)15 A data center is a specialized IT infrastructure thathouses centralized IT resources, such as servers,databases, and software systems. Data center IT hardware is typically comprises ofstandardized commodity servers of increasedcomputing power and storage capacity, while storagesystem technologies include disk arrays and storagevirtualization. Technologies used to increase storagecapacity include DAS, SAN, and NAS.

Summary of Data Center Technology (2/2)16 Computing hardware technologies include rack-mounted server arrays and multi-core CPUarchitectures, while specialized high-capacitynetwork hardware and technology, such as contentaware routing, LAN and SAN fabrics, and NASgateways, are used to improve network connectivity.

5.3 Virtualization Technology (1/2)17 Most types of IT resources can be virtualized:servers, storage, network, power. Hardware Independence Server Consolidation Different virtual servers share one physical server Resource Replication Virtual disk images can be accessible using simple fileoperations, such as copy, move, and paste by the host’s OS forreplication purpose

5.3 Virtualization Technology (2/2)18 Operating System-Based Virtualization (Figure 5.8) Hardware-Based Virtualization (Figure 5.9) Virtualization Management Virtualization infrastructure management (VIM) collectivelymanage virtual IT resources running on a centralized module. Other Considerations Performance overhead Special hardware compatibility Portability (Open Virtualization Format OVF)

Figure 5.819 Figure 5.8 - The differentlogical layers ofoperating system-basedvirtualization, in whichthe VM is first installedinto a full host operatingsystem and subsequentlyused to generate virtualmachines.

Figure 5.920 Figure 5.9 - The different logical layers of hardware-basedvirtualization, which does not require another host operating system.

Summary of Virtualization Technology21 Server virtualization is the process of abstracting IThardware into virtual servers using virtualizationsoftware. Virtualization provides hardware independence,server consolidation, and resource replication, andfurther supports resource pooling and elasticscalability. Virtual servers are realized through either operatingsystem-based or hardware-based virtualization.

5.4 Web Technology22 Basic Web Technology Uniform Resource Locator (URL) Hypertext Transfer Protocol (HTTP) Markup Language (HTMP, XML) Web Applications (Figure 5.10) Presentation layer (user interface) Application layer (application logic in application server) Data layer (data store in data server)

Figure 5.1023 Figure 5.10 - The three basic architectural tiers of Web applications.

Summary of Web Service24 Web technology is very commonly for cloud serviceimplementations and for front-ends used to remotelymanage cloud-based IT resources. For instance, typical PaaS offerings have separate instances ofthe Web server, application server, and data server. Fundamental technologies of Web architectureinclude the URL, HTTP, HTML, and XML.

5.5 Multitenant Technology25 Multitenant – a single instance of an IT resourceserves multiple consumers (tenants). Multitenant application architecture is oftensignificantly more complex than that of single-tenantapplications. Multi-tenant applications need to support thesharing of various artifacts by multiple users(including portals, data schemas, middleware, anddatabases), while maintaining security levels thatsegregate individual tenant operationalenvironments.

5.5 Characteristics of Multitenant26 Usage isolation Data security Recovery Application upgrades Scalability Metered usage Data tier isolation Multitenancy is sometimes mistaken for virtualizationbecause the concept of multiple tenants is similar to theconcept of virtualized instances.

Figure 5.1127 Figure 5.11 - A multitenantapplication that is servingmultiple cloud serviceconsumers simultaneously.

Multitenancy VS. Virtualization28 The differences lie in what is multiplied within aphysical server acting as a host: With virtualization: Multiple virtual copies of the server environment can behosted by a single physical serve. Each copy can be providedto different users, can be configured independently, and cancontain its own operating system and applications.With multitenancy: A physical or virtual server hosting an application isdesigned to allow usage by multiple different users. Eachuser feels as though they have exclusive usage of theapplication.

5.6 Service Technology29 Along with XML, the core technologies behind Webservices are represented by the following industrystandards:Web Service Description Language (WSDL) XML Schema Definition Language (XML Schema) SOAP (Simple Object Access Protocol) Universal Description, Discovery, and Integration (UDDI) Note that: These 4 technologies collectively form thefirst generation of Web service technology. The 2ndgeneration (WS-*) addresses additional features, suchas security, reliability, transactions, routing, andbusiness process automation.

Figure 5.1230 Figure 5.12 - An overviewof how first-generationWeb service technologiescommonly relate to eachother

REST Service and Service Agents31 REST services are designed according to a set ofconstraints that shape the service architecture toemulate the properties of the WWW. Service agents are event-driven programs designed tointercept messages at runtime, either active agent orpassive agent. Falling under the umbrella of service technology is thelarge of middle platform. Two main categories are theenterprise service bus (ESB) and the orchestrationplatform.

Summary of Service Technology32 Web-based services such as Web services and RESTservices rely on non-proprietary communicationsand technical interface definitions to establishstandardized communications frameworks based onWeb technology. Service agents provide event-driven runtimeprocessing that can be applied to numerousfunctional areas within clouds. Service middleware, such as ESBs and orchestrationplatforms, can be deployed on clouds.

Figure 5.1333 Figure 5.13 - A view ofthe server networkconnections inside theDTGOV data center.

Figure 5.1434 Figure 5.14 - A view of thestorage system networkconnections inside theDTGOV data center.

Chapter 05 Cloud-Enabling Technology. Cloud Computing. Concept, Technology & Architecture. 課程名稱:雲端管理系統 授課教師:高勝助. Contents. Contemporary technologies that realize modern- day cloud computing platforms and innovations are discussed, particularly data centers, virtualization, and Web-based technologies.