Cloud Computing Principles and Paradigms: 3 enriching the integration as a service paradigm for the cloud era

Editor's Notes

• #3: clouds guarantee most of the non-function requirements (Quality of Service (QoS) attributes) such as availability, high performance, on-demand scalability/elasticity, affordability, global-scale accessibility and usability, energy efficiency etc.---------------------------------------------------------------------------However most of the confidential and corporate data are still being maintained in enterprise servers for security reasons.---------------------------------------------------------------------------
• #4: clouds are set to decimate all kinds of IT inflexibility and dawn a growing array of innovations to prepare the present day IT for sustainable prosperity.IT as a Service (ITaaS) is the most recent and efficient delivery method in the decisive IT landscape.every single IT resource, activity and infrastructure is being viewed and visualized as a service that sets the tone for the grand unfolding of the dreamt service eraClouds, as indicated above, is the most visible and viable infrastructure for realizing ITaaS--------------------------------------------------------------------------------------------------------------------------Integration as a service (IaaS) is the budding(جوانه) and distinctive(مشخص) capability of clouds in fulfilling the business integration requirements.Increasingly business applications are deployed in clouds to reap(درو کردن) the business and technical benefits. On the other hand, there are still innumerable applications and data sources locally stationed and sustained primarily due to the security reason.The question here is how to create a seamless connectivity between those hosted and on-premise applications to empower them to work together. The use of hub & spoke (H&S) architecture further simplifies the implementation and avoids placing an excessive processing burden on the customersides. The hub is installed at the SaaS provider’s cloud center to do the heavy lifting such as reformatting files. A spoke unit at each user site typically acts as basic data transfer utility.
• #5: companies without a method of synchronizing data between multiple lines of businesses are at a serious disadvantage in terms of maintaining accurate data, forecasting, and automating key business processes. Real-time data and functionality sharing is an essential ingredient(جزء) for clouds.integration methodologies and middleware solutions have to take clouds too into account for establishing extended and integrated processes and views.Many SaaS providers have responded to the integration challenge by developing application programming interfaces (APIs).Integration has been a big challenge for growing business behemoths(کل)
• #6: Integration as a Service (IaaS) is all about the migration of the functionality of a typical enterprise application integration (EAI) hub / enterprise service bus(ESB) into the cloud for providing for smooth data transport between any enterprise and SaaS applications.--------------------------------------------------------------------------------------------------------------Cloud middleware is the next logical evolution of traditional middleware solutions. That is, cloud middleware will be made available as a service.------------------------------------------------------------------------------------Service interaction through ESB integrates loosely coupled systems whereas CEP connects decoupled systems.--------------------------Cloud infrastructure is not very useful without SaaS applications that run on top of them, and SaaS applications are not very valuable without access to the critical corporate data that is typically locked away in various corporate systems.
• #7: data integrity issues, which are a natural phenomenon when data is being updated using different procedures, and there is no active synchronization between the SaaS and on-premise systems.Dynamic nature of the SaaS interfaces that constantly change Dynamic nature of the metadata native to a SaaS provider such as Salesforce.comManaging assets that exist outside of the firewallMassive amounts of information that need to move between SaaS and on-premise systems daily and the need to maintain data quality and integrity--------------------------------------------------------------------------Complicated integration New integration scenarios Access to the cloud may be limited Dynamic resources PerformanceFor example, the SalesForce.com web services API does not support transactions against multiple records, which means integration code has to handle that logic.the network distances between elements in the cloud are no longer under our control. Bandwidth is not the limiting factor in most integration scenarios but the round trip latency is an issue not to be sidestepped.
• #10: The applications to be integrated are posited in two geographically separated cloud infrastructures. The integration middleware can be in cloud 1 or 2 or in a separate cloud. There is a need for data and protocol transformation and they get done by the ISB. The approach is more or less compatible to enterprise application integration procedure.
• #11: The first two scenarios will become prevalent once there are several commercial clouds and cloud services become pervasive.
• #12: i)With a persistent rise in the necessity towards accessing and integrating cloud applications, special drivers, connectors and adapters are being built and incorporated on the existing integration platforms to enable bidirectional connectivity with the participating cloud services.----------------------------------------------ii)The IT divisions of business enterprises need not worry about the upfront investment of high-end computer machines, integration packages, and their maintenance with this approach.----------------------------------------------
• #15: Mr. David Linthicum:Design:This defines how the data is to be extracted from one system or systems, transformed so it appears to be native, and then updated in the target system or systems-----------------------------------------------Test:Testing refers to assuring that the integration is properly designed and implemented and that the data synchronizes properly between the involved systems. -----------------------------------------------
• #20: Informatica offers a set of innovative on-demand data integration solutions called Informatica On-Demand Services. This is a cluster of easy-to-use SaaSofferings, which facilitate integrating data in SaaS applications, seamlessly and securely across the Internet with data in on-premise applications. The Informatica on-demand service is a subscription-based integration service that provides all the relevant features and functions, using an on-demand or anas-a-service delivery model.when developing new features or enhancements, they are immediately made available to all of their customers transparently.
• #21: azure makes development, depositing and delivering Web and Windows application on cloud centers easier and cost-effective. The Access Control Service allows applications to rely on .NET Services solution
• #22: Service Bus is messaging infrastructure that sits between applications allowing them to exchange messages in a loosely coupled way for improved scale and resiliency. Service Bus is managed and operated by Microsoft with a 99.9% monthly SLA.Use Service Bus to: Manage message delivery in the cloud Connect on-premises applications to the cloudCapabilities:A federated namespace modelA service registry servicelightweight and scalable publish/subscribe event busA relay and connectivity service
• #23: ACS is a Windows Azure service that provides an easy way of authenticating users who need to access your web applications and services without having to factor complex authentication logic into your code. Like login to facebook.The client (in this case a browser) requests a page from the RP(Relaying party).Since the request is not yet authenticated, the RP redirects the user to the authority that it trusts, which is ACS. The ACS presents the user with the choice of IPs that were specified for this RP. The user selects the appropriate IP(identity provider).The client browses to the IP's authentication page, and prompts the user to log on.After the client is authenticated (for example, the identity credentials are entered), the IP issues a security token.After issuing a security token, the IP redirects the client to ACS and the client sends the security token issued by the IP to ACS.ACS validates the security token issued by the IP, inputs the identity claims in this token into the ACS rules engine, calculates the output identity claims, and issues a new security token that contains these output claims.ACS redirects the client to the RP. The client sends the new security token issued by ACS to the RP. The RP validates the signature on the security token issued by ACS, validates the claims in this token, and returns the page that was originally requested.
• #24: When we are having the service call-backs to the client, the connectivity challenges lead to scalability, availability and security issues. The solution to Internet connectivity challenges is instead of connecting client directly to the service we can use a relay service as pictorially represented in the relay service.The Relay service is a service residing in the cloud whose job is to assist the connectivity and relaying the calls to the service. Relay Service solution requireboth the client and the service intranets to allow connections to the cloud.
• #25: The diagram describes the process of a message being delivered and handled by the Mashup Integration Services Platform. The precondition for this process is that a user already established a route to a recipient. After having received a message from an Enterprise Mashup tool via an API, the Integration Services first check the access rights of the sender of the message against an external service. An incoming message is processed only if sender of the message is authorized, that is, he has the right to deliver the message to the recipient and to use the Mashup integration services. If he is not authorized, the processing stops, and an error message gets logged. The error log message is written into a log file, which could reside on Amazon’s Simple Storage Service (S3). If the message has been accepted, it is put in the message queue in Amazon’s SQS service. If required, the message is being translated into another format, which can also be done by an external, cloudbased service. After that, the services can begin trying delivering the message to a recipient. Evaluating the recipients of the message is based on the rules stored in the routing engine which have been configured by a user before. Finally, the successful delivery of the message can be logged, or an error if one occurred.
• #26: Users register their information and subscriptions to various SaaS applications which then transfer all this information to pub/sub broker registry. Whensensor data reaches to the system from gateways, event/stream monitoring and processing component (SMPC) in the pub/sub broker determines whether it needs processing or just store for periodic send or for immediate delivery. If sensor data needs periodic/ emergency delivery, the analyzer determines which SaaS applications the events belong to and then passes the events to the disseminator along with application ids. The disseminator, using the eventmatching algorithm, finds appropriate subscribers for each application and delivers the events for use.Besides the pub-sub broker, the authors have proposed to include three other components: mediator, policy repository (PR) and collaborator agent(CA) along with system manager, provisioning manager, monitoring and metering and service registry in the sensor-cloud framework to enable VObased dynamic collaboration of primary cloud providers with other cloud providers in case of SLA violations for burst resource demand. These threecomponents collectively act as a “gateway” for a given CLP in creation of a new VO.