[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"cheat-sheet---en":3,"domain-info---en":3,"topic-info----en":3,"lesson-cloud-computing-fundamentals-cloud-services-and-architecture-cloud-service-models-software-as-a-service-en":4,"next-cloud-computing-fundamentals-cloud-services-and-architecture-cloud-service-models-software-as-a-service-en":265,"prev-cloud-computing-fundamentals-cloud-services-and-architecture-cloud-service-models-software-as-a-service-en":522},null,{"locked":5,"reason":3,"meta":6,"item":16},false,{"title":7,"description":8,"isFree":5,"estimatedMinutes":9,"difficulty":10,"learningObjectives":11},"Software as a Service (SaaS)","The service model where the provider runs the entire application and you just use it, from Gmail to Salesforce to Slack, and the multi-tenant architecture that makes running one application for millions of customers affordable.",14,"beginner",[12,13,14,15],"Define Software as a Service (SaaS) using the NIST framework","Explain multi-tenancy and why it makes SaaS pricing possible","Identify what a SaaS customer can and cannot configure","Distinguish genuine SaaS from a locally installed, subscription-priced application",{"id":17,"title":7,"body":18,"description":8,"difficulty":10,"estimatedMinutes":9,"extension":205,"infographics":206,"isFree":5,"learningObjectives":207,"meta":208,"navigation":209,"path":210,"quiz":211,"seo":262,"stem":263,"__hash__":264},"courses/courses/cloud-computing-fundamentals/en/domains/02-cloud-services-and-architecture/01-cloud-service-models/03-software-as-a-service.md",{"type":19,"value":20,"toc":193},"minimark",[21,26,30,34,37,40,44,116,119,123,126,129,133,179,183,186,190],[22,23,25],"h2",{"id":24},"you-already-used-saas-today","You already used SaaS today",[27,28,29],"p",{},"You did not install a mail server this morning. You did not patch an operating system, provision a virtual machine, or write a line of code. You typed a password into a browser, and your inbox was already there, running on hardware you have never seen, maintained by a team you have never met. That is Software as a Service, and unlike the last 2 lessons, you almost certainly used it before you finished breakfast.",[22,31,33],{"id":32},"the-nist-definition-in-practice","The NIST definition, in practice",[27,35,36],{},"NIST defines SaaS as the capability to \"use the provider's applications running on a cloud infrastructure,\" reachable \"through either a thin client interface, such as a web browser... or a program interface.\" The consumer does not manage or control the underlying cloud infrastructure, including network, servers, operating systems, storage, or even individual application capabilities, with the possible exception of limited user-specific application configuration settings.",[27,38,39],{},"That exception is doing real work in the sentence. You cannot install a plugin on Gmail's servers or change which programming language Salesforce is written in. You can set up an email filter or customize a Salesforce dashboard. The application itself, and everything beneath it, belongs entirely to the provider.",[22,41,43],{"id":42},"who-manages-what-complete","Who manages what, complete",[45,46,47,66],"table",{},[48,49,50],"thead",{},[51,52,53,57,60,63],"tr",{},[54,55,56],"th",{},"Layer",[54,58,59],{},"IaaS",[54,61,62],{},"PaaS",[54,64,65],{},"SaaS",[67,68,69,82,94,105],"tbody",{},[51,70,71,75,78,80],{},[72,73,74],"td",{},"Networking, servers, virtualization",[72,76,77],{},"Provider",[72,79,77],{},[72,81,77],{},[51,83,84,87,90,92],{},[72,85,86],{},"Operating system, runtime",[72,88,89],{},"You",[72,91,77],{},[72,93,77],{},[51,95,96,99,101,103],{},[72,97,98],{},"Application code",[72,100,89],{},[72,102,89],{},[72,104,77],{},[51,106,107,110,112,114],{},[72,108,109],{},"Data and user configuration",[72,111,89],{},[72,113,89],{},[72,115,89],{},[27,117,118],{},"Data and your own configuration are the one row that never moves. Every other layer eventually crosses to the provider by the time you reach SaaS.",[22,120,122],{"id":121},"multi-tenancy-the-architecture-that-makes-this-affordable","Multi-tenancy: the architecture that makes this affordable",[27,124,125],{},"A SaaS vendor is not running a separate copy of Gmail for each of its billions of users. Gartner describes multitenancy as software where a single instance serves multiple customers, logically isolated from each other but physically sharing the same infrastructure underneath. Your inbox and a stranger's inbox run on the same application instance, the same servers, with the provider's software guaranteeing neither of you can see the other's data.",[27,127,128],{},"That sharing is exactly what makes SaaS pricing work. Spreading one application instance across millions of tenants is dramatically cheaper per customer than running a dedicated copy for each one, which is why a SaaS subscription usually costs a small fraction of what building and hosting the same application yourself would.",[22,130,132],{"id":131},"real-products-by-category","Real products, by category",[45,134,135,145],{},[48,136,137],{},[51,138,139,142],{},[54,140,141],{},"Category",[54,143,144],{},"Examples",[67,146,147,155,163,171],{},[51,148,149,152],{},[72,150,151],{},"Email and productivity",[72,153,154],{},"Gmail, Microsoft 365",[51,156,157,160],{},[72,158,159],{},"Customer relationship management",[72,161,162],{},"Salesforce",[51,164,165,168],{},[72,166,167],{},"Team communication",[72,169,170],{},"Slack, Zoom",[51,172,173,176],{},[72,174,175],{},"File storage and collaboration",[72,177,178],{},"Dropbox, Google Workspace",[22,180,182],{"id":181},"the-misconception-a-subscription-is-not-the-same-thing-as-saas","The misconception: a subscription is not the same thing as SaaS",[27,184,185],{},"It is tempting to call anything billed monthly \"SaaS.\" It is not. A boxed application you install on your own laptop, and personally keep updated, does not become SaaS just because its license renews every month. The test is not the billing model, it is who runs it and where. If the provider hosts, patches, and operates the application on infrastructure you never touch, and you reach it through a browser or an API, it is SaaS. If you installed it yourself and you are the one applying its updates, it is not, no matter how the invoice arrives.",[22,187,189],{"id":188},"where-this-leaves-you","Where this leaves you",[27,191,192],{},"SaaS is the end of the handoff that started with IaaS: the provider now runs the operating system, the runtime, and the application itself, and the only thing left on your side of the line is your data and your own settings. You have now met all 3 service models individually. The next lesson puts them side by side and gives you the boundary an exam actually tests: not what each one is, but which one a scenario is describing.",{"title":194,"searchDepth":195,"depth":195,"links":196},"",3,[197,199,200,201,202,203,204],{"id":24,"depth":198,"text":25},2,{"id":32,"depth":198,"text":33},{"id":42,"depth":198,"text":43},{"id":121,"depth":198,"text":122},{"id":131,"depth":198,"text":132},{"id":181,"depth":198,"text":182},{"id":188,"depth":198,"text":189},"md",[],[12,13,14,15],{},true,"/courses/cloud-computing-fundamentals/en/domains/02-cloud-services-and-architecture/01-cloud-service-models/03-software-as-a-service",{"passingScore":212,"questions":213},70,[214,223,229,237,246,254],{"question":215,"type":216,"options":217,"correctAnswer":221,"explanation":222},"Which of these best matches the NIST definition of SaaS?","single",[218,219,220,221],"The consumer provisions virtual machines and manages the operating system","The consumer deploys their own code onto infrastructure they do not manage","The consumer builds and hosts their own web application","The consumer uses the provider's application, reached through a browser or API, without managing anything underneath it","SaaS means the provider runs the entire application, network, servers, OS, and the application itself, and the consumer just uses it through a thin client like a browser or a program interface. The first 2 options describe IaaS and PaaS, and the third describes building software yourself, not consuming it as a service.",{"question":224,"type":216,"options":225,"correctAnswer":227,"explanation":228},"According to NIST, a SaaS customer has no ability to configure anything about the application, not even their own account settings.",[226,227],"True","False","NIST's SaaS definition specifically carves out an exception for limited user-specific application configuration settings, such as setting up an email filter or customizing a dashboard. What the customer cannot do is change the underlying infrastructure or the application's core code.",{"question":230,"type":216,"options":231,"correctAnswer":232,"explanation":236},"In a multi-tenant SaaS application, how are different customers' data typically kept separate?",[232,233,234,235],"Customers share the same application instance and underlying infrastructure, but the provider logically isolates each tenant's data","Each customer gets an entirely separate copy of the application running on dedicated hardware","Data is not actually separated, all customers can see all data","Each customer must build their own isolation layer","Multitenancy means many customers share one application instance and its infrastructure, with the provider's software guaranteeing logical isolation between them even though they are physically integrated. A dedicated copy per customer describes single-tenant architecture, which is the more expensive alternative SaaS providers generally avoid.",{"question":238,"type":239,"options":240,"correctAnswers":244,"explanation":245},"Which of the following are genuinely SaaS products? (Select all that apply.)","multiple",[162,241,242,243],"AWS EC2","Gmail","Google App Engine",[162,242],"Salesforce and Gmail are complete applications the provider runs entirely, which you access through a browser without managing anything underneath, the SaaS pattern. AWS EC2 hands you a virtual machine to manage yourself, IaaS, and Google App Engine runs your own code for you, PaaS, so neither qualifies as SaaS.",{"question":247,"type":216,"options":248,"correctAnswer":251,"explanation":253},"A company sells a desktop application under a monthly subscription. Customers install it themselves on their own laptops and are responsible for applying its updates. Is this SaaS?",[249,250,251,252],"Yes, because it is billed monthly like a subscription","Yes, because all modern software subscriptions count as SaaS","No, because the customer installs and maintains it themselves rather than the provider hosting and running it","No, because SaaS must always be free","The test for SaaS is not the billing model, it is who runs the application and where. Software the customer installs and personally updates on their own device is not SaaS, no matter how the invoice arrives, because the provider never hosts or operates it.",{"question":255,"type":216,"options":256,"correctAnswer":258,"explanation":261},"Why does multi-tenancy typically make SaaS pricing cheaper per customer than a dedicated, self-hosted version of the same application?",[257,258,259,260],"It doesn't, self-hosting is always cheaper","One application instance and its infrastructure are shared across many customers instead of duplicated for each one","SaaS vendors do not have to pay for servers at all","Multi-tenancy has nothing to do with pricing","Spreading one application instance across millions of tenants is dramatically cheaper per customer than running a dedicated copy for each one, which is exactly why SaaS subscriptions usually undercut the cost of building and hosting the same application privately. SaaS vendors still pay for servers, they just divide that cost across every tenant sharing them.",{"title":7,"description":8},"courses/cloud-computing-fundamentals/en/domains/02-cloud-services-and-architecture/01-cloud-service-models/03-software-as-a-service","Bz80kzlz2lf2a_WX0U_WjpUYEdYVwZpvHa09s8CmK5E",{"locked":5,"reason":3,"meta":266,"item":276},{"title":267,"description":268,"isFree":5,"estimatedMinutes":269,"difficulty":270,"learningObjectives":271},"IaaS vs. PaaS vs. SaaS","The full responsibility split across all 3 service models side by side, the keyword cues that identify each one in a scenario, and the classic trap that catches learners who assume moving up the stack always means an upgrade.",19,"intermediate",[272,273,274,275],"Compare the full responsibility split across IaaS, PaaS, and SaaS, layer by layer","Apply keyword cues to identify the correct service model in a scenario","Explain why moving up the stack trades control for convenience rather than simply improving","Evaluate a scenario against its constraints to select the service model that fits",{"id":277,"title":267,"body":278,"description":268,"difficulty":270,"estimatedMinutes":269,"extension":205,"infographics":451,"isFree":5,"learningObjectives":462,"meta":463,"navigation":209,"path":464,"quiz":465,"seo":519,"stem":520,"__hash__":521},"courses/courses/cloud-computing-fundamentals/en/domains/02-cloud-services-and-architecture/01-cloud-service-models/04-iaas-vs-paas-vs-saas.md",{"type":19,"value":279,"toc":442},[280,284,287,291,360,365,368,372,375,379,382,417,421,424,427,430,434,437,439],[22,281,283],{"id":282},"naming-them-is-easy-telling-them-apart-is-the-actual-skill","Naming them is easy. Telling them apart is the actual skill",[27,285,286],{},"You can now define IaaS, PaaS, and SaaS individually. That is not, on its own, a useful skill: almost nobody hands you a service and asks \"what is this?\" in isolation. What actually gets tested, on an exam and on the job, is a scenario with constraints, a team, a deadline, a compliance requirement, and the question of which of the 3 models fits it. That is where this lesson spends its effort.",[22,288,290],{"id":289},"the-full-stack-side-by-side","The full stack, side by side",[45,292,293,305],{},[48,294,295],{},[51,296,297,299,301,303],{},[54,298,56],{},[54,300,59],{},[54,302,62],{},[54,304,65],{},[67,306,307,317,328,339,349],{},[51,308,309,311,313,315],{},[72,310,74],{},[72,312,77],{},[72,314,77],{},[72,316,77],{},[51,318,319,322,324,326],{},[72,320,321],{},"Operating system",[72,323,89],{},[72,325,77],{},[72,327,77],{},[51,329,330,333,335,337],{},[72,331,332],{},"Runtime and middleware",[72,334,89],{},[72,336,77],{},[72,338,77],{},[51,340,341,343,345,347],{},[72,342,98],{},[72,344,89],{},[72,346,89],{},[72,348,77],{},[51,350,351,354,356,358],{},[72,352,353],{},"Data and your own configuration",[72,355,89],{},[72,357,89],{},[72,359,89],{},[361,362],"infographic",{"alt":363,"slug":364},"A 3-column stack diagram comparing IaaS, PaaS, and SaaS, showing which layers the provider manages and which stay with the customer, with data and configuration always remaining the customer's responsibility.","iaas-vs-paas-vs-saas-responsibility-stack",[27,366,367],{},"Read the table by column instead of by row and the pattern is obvious: each step from IaaS to SaaS moves exactly one more layer from \"you\" to \"provider.\" Data and your own configuration are the only row that never moves, no matter which model you pick.",[22,369,371],{"id":370},"the-trap-this-is-a-tradeoff-not-a-ranking","The trap: this is a tradeoff, not a ranking",[27,373,374],{},"It is tempting to read that table left to right and conclude SaaS is simply the best model, since the provider does the most work. That conclusion is wrong, and it is exactly the trap an exam question sets. What SaaS gains in convenience, it spends in control. You cannot install a custom library on Gmail's servers, run your own code on Salesforce's infrastructure, or choose a different kernel version for Microsoft 365. IaaS gives you all of that control back, at the cost of doing the OS, runtime, and application management yourself. Neither end of the table is \"better.\" Each one fits a different set of constraints.",[22,376,378],{"id":377},"keyword-cues-for-scenarios","Keyword cues for scenarios",[27,380,381],{},"Exam scenarios rarely say \"IaaS\" or \"PaaS\" directly. They describe a constraint, and the constraint points at the model.",[45,383,384,394],{},[48,385,386],{},[51,387,388,391],{},[54,389,390],{},"The scenario says...",[54,392,393],{},"Points to",[67,395,396,403,410],{},[51,397,398,401],{},[72,399,400],{},"\"Full control of the operating system,\" \"specific kernel version,\" \"root access\"",[72,402,59],{},[51,404,405,408],{},[72,406,407],{},"\"Just deploy the code,\" \"no server management,\" \"focus on the application\"",[72,409,62],{},[51,411,412,415],{},[72,413,414],{},"\"No installation,\" \"use it out of the box,\" \"no developers on staff\"",[72,416,65],{},[22,418,420],{"id":419},"worked-example-2-scenarios-2-answers","Worked example: 2 scenarios, 2 answers",[27,422,423],{},"A 12-person sales team needs a working CRM by next week and has no developers on staff to build one. Nothing about this scenario mentions code, infrastructure, or customization beyond configuration. That absence is the cue: this is a SaaS scenario, and a tool like Salesforce is the fit, not something a team builds from scratch.",[27,425,426],{},"Now change the constraint. A fintech company operates under a regulation that requires it to control the exact OS patch level running on every server, down to the kernel version, and to apply security patches on its own schedule rather than a vendor's. PaaS and SaaS both take the operating system out of the customer's hands, which is precisely the control this regulation demands. That single requirement rules out both, and leaves IaaS as the only model that fits.",[27,428,429],{},"Same underlying question in both cases: how far up the stack does this scenario require you to reach. The sales team's answer is \"not at all.\" The fintech company's answer is \"all the way down to the kernel.\"",[22,431,433],{"id":432},"the-connection-to-shared-responsibility","The connection to shared responsibility",[27,435,436],{},"This same layer-by-layer split is the foundation of the shared responsibility model, covered in full in this course's Security and Reliability domain. What you are learning here, which layer belongs to you and which belongs to the provider, is the exact question that model answers for security specifically. You are not learning a new idea there. You are applying this one to a new question.",[22,438,189],{"id":188},[27,440,441],{},"One question separates these 3 models in any scenario: how far up the stack does the situation require the provider to go. Root access and kernel control pull you toward IaaS. A focus on shipping code with no server management pulls you toward PaaS. No installation and no in-house developers pulls you toward SaaS. The next topic in this domain leaves the service models behind and moves to the building blocks every one of them runs on: regions, compute, storage, databases, and networking.",{"title":194,"searchDepth":195,"depth":195,"links":443},[444,445,446,447,448,449,450],{"id":282,"depth":198,"text":283},{"id":289,"depth":198,"text":290},{"id":370,"depth":198,"text":371},{"id":377,"depth":198,"text":378},{"id":419,"depth":198,"text":420},{"id":432,"depth":198,"text":433},{"id":188,"depth":198,"text":189},[452],{"slug":364,"concept":453,"style":454,"aspectRatio":455,"labels":456},"A 3-column stack diagram, one column per service model (IaaS, PaaS, SaaS), each built from the same layers stacked bottom to top: networking and servers, virtualization, operating system, runtime and middleware, application code, and data. In each column, the layers the provider manages are shaded one color and the layers the customer manages are shaded a contrasting second color. Moving left to right from IaaS to SaaS, the provider-shaded portion grows taller and the customer-shaded portion shrinks, visually showing the responsibility handoff. A footer strip carries the tradeoff takeaway.","diagram","16:9",[457,458,459,460,461],"IaaS: Provider manages networking, servers, and virtualization. You manage the OS, runtime, and app.","PaaS: Provider also takes over the OS and runtime. You manage the app code and data.","SaaS: Provider manages the entire application. You manage only your data and settings.","Data and access are always yours, in every model.","Moving right trades control for convenience. It is not an upgrade, it is a tradeoff.",[272,273,274,275],{},"/courses/cloud-computing-fundamentals/en/domains/02-cloud-services-and-architecture/01-cloud-service-models/04-iaas-vs-paas-vs-saas",{"passingScore":212,"questions":466},[467,472,477,481,487,496,504,512],{"question":468,"type":216,"options":469,"correctAnswer":65,"explanation":471},"A 12-person sales team needs a working CRM next week and has no developers on staff. Which service model fits best?",[62,65,59,470],"None, they must hire developers first","With no developers on staff and a working tool needed fast, SaaS fits: a complete application like Salesforce is ready to configure and use immediately. IaaS and PaaS both assume someone on the team is writing or deploying code, which this scenario rules out.",{"question":473,"type":216,"options":474,"correctAnswer":59,"explanation":476},"A fintech company is legally required to control the exact OS kernel version on every server it runs. Which service model is the only one that satisfies this requirement?",[65,62,475,59],"Either PaaS or SaaS, since both are managed by the provider","Only IaaS leaves the operating system, including the kernel version, in the customer's hands. PaaS and SaaS both move the OS to the provider, which is exactly the control this regulation requires the company to keep for itself.",{"question":478,"type":216,"options":479,"correctAnswer":227,"explanation":480},"Moving from IaaS toward SaaS is always an improvement, since the provider takes on more of the work.",[226,227],"What SaaS gains in convenience, it spends in control: you cannot install custom code on Gmail's servers or choose Salesforce's kernel version. Each model fits different constraints, so moving up the stack is a tradeoff, not a straightforward upgrade.",{"question":482,"type":216,"options":483,"correctAnswer":353,"explanation":486},"According to the responsibility split, which layer is the customer responsible for in every one of the 3 service models, without exception?",[353,484,98,485],"The operating system","Virtualization","Data and your own configuration are the one row that never moves across IaaS, PaaS, or SaaS. The operating system and application code shift to the provider at different points in the stack, and virtualization belongs to the provider in all 3 models.",{"question":488,"type":239,"options":489,"correctAnswers":494,"explanation":495},"Which of the following phrases in a scenario would point toward PaaS rather than IaaS or SaaS? (Select all that apply.)",[490,491,492,493],"Full control of the operating system","Focus on deploying application code, no server management","No installation required, just log in and use it","The team wants to write and ship code without managing infrastructure",[491,493],"PaaS scenarios describe a team writing and shipping their own code while the platform handles servers and the OS. \"Full control of the operating system\" points to IaaS, and \"no installation required\" points to SaaS, since neither involves the customer deploying their own application code.",{"question":497,"type":216,"options":498,"correctAnswer":501,"explanation":503},"Why can a company not simply say SaaS is the best service model for every situation?",[499,500,501,502],"SaaS is always more expensive than IaaS","SaaS is technically inferior to IaaS and PaaS","SaaS trades away control that some scenarios genuinely require, such as running custom code or controlling the OS","SaaS does not actually exist as a real deployment option","SaaS is not inferior or superior to the other models, it is a different point on the same control-versus-convenience tradeoff. A scenario that needs custom code or OS-level control rules SaaS out regardless of how convenient it otherwise is.",{"question":505,"type":216,"options":506,"correctAnswer":508,"explanation":511},"Which service model does the shared responsibility model, covered later in this course, build directly on?",[507,508,509,510],"A completely separate framework unrelated to service models","The same layer-by-layer split between customer and provider covered in this topic","Only the SaaS model","Only the IaaS model","The shared responsibility model applies the same customer-versus-provider split you just learned specifically to security. It is not a new framework, it is this one, pointed at a specific question.",{"question":513,"type":216,"options":514,"correctAnswer":517,"explanation":518},"A team deploys an application through a PaaS product. Compared to IaaS, which additional layer does the provider now manage?",[98,515,516,517],"Data","Networking","The operating system and runtime","The operating system and runtime are the layers that move from customer to provider between IaaS and PaaS. Application code and data stay with the customer in both models, and networking is already the provider's job under IaaS.",{"title":267,"description":268},"courses/cloud-computing-fundamentals/en/domains/02-cloud-services-and-architecture/01-cloud-service-models/04-iaas-vs-paas-vs-saas","aqcJIr7pB2vb9kCvpVwqkButhpb5OOlPapjCzJzT8Z0",{"locked":5,"reason":3,"meta":523,"item":532},{"title":524,"description":525,"isFree":5,"estimatedMinutes":526,"difficulty":10,"learningObjectives":527},"Platform as a Service (PaaS)","The service model that takes the operating system and runtime off your plate, so you push code and the platform runs it, with AWS Elastic Beanstalk, Heroku, and Google App Engine as the products that deliver it.",15,[528,529,530,531],"Define Platform as a Service (PaaS) using the NIST framework","Identify which layers move from customer to provider between IaaS and PaaS","Contrast deploying the same application through IaaS and through PaaS","Explain the boundary between PaaS and the serverless model covered later in this course",{"id":533,"title":524,"body":534,"description":525,"difficulty":10,"estimatedMinutes":526,"extension":205,"infographics":686,"isFree":5,"learningObjectives":687,"meta":688,"navigation":209,"path":689,"quiz":690,"seo":732,"stem":733,"__hash__":734},"courses/courses/cloud-computing-fundamentals/en/domains/02-cloud-services-and-architecture/01-cloud-service-models/02-platform-as-a-service.md",{"type":19,"value":535,"toc":676},[536,540,543,545,548,551,555,609,612,616,644,648,654,657,661,664,668,671,673],[22,537,539],{"id":538},"what-if-you-never-wanted-to-touch-the-operating-system-at-all","What if you never wanted to touch the operating system at all",[27,541,542],{},"The previous lesson ended with you owning an EC2 instance: patching its OS, installing a runtime, configuring a firewall. Now picture a solo developer with a web app to ship by Friday and zero interest in any of that. They do not want to choose an AMI, size a load balancer, or read a patch changelog. They want to hand over code and have it run. Platform as a Service is the model built for exactly that handoff.",[22,544,33],{"id":32},[27,546,547],{},"NIST defines PaaS as the capability to \"deploy onto the cloud infrastructure consumer-created or acquired applications created using programming languages, libraries, services, and tools supported by the provider.\" The consumer does not manage the underlying infrastructure, including network, servers, operating systems, or storage, but does control the deployed application and, often, configuration settings for the environment that hosts it.",[27,549,550],{},"Read that against the IaaS definition from the last lesson and the shift is precise: the operating system, which was yours in IaaS, now belongs to the provider. What is left for you is the application itself and the settings around how it runs.",[22,552,554],{"id":553},"who-manages-what-updated","Who manages what, updated",[45,556,557,567],{},[48,558,559],{},[51,560,561,563,565],{},[54,562,56],{},[54,564,59],{},[54,566,62],{},[67,568,569,577,585,593,601],{},[51,570,571,573,575],{},[72,572,74],{},[72,574,77],{},[72,576,77],{},[51,578,579,581,583],{},[72,580,321],{},[72,582,89],{},[72,584,77],{},[51,586,587,589,591],{},[72,588,332],{},[72,590,89],{},[72,592,77],{},[51,594,595,597,599],{},[72,596,98],{},[72,598,89],{},[72,600,89],{},[51,602,603,605,607],{},[72,604,515],{},[72,606,89],{},[72,608,89],{},[27,610,611],{},"The whole shift is in one row: the operating system and runtime cross the line from \"you\" to \"provider.\" That is the entire difference between the 2 models, and it deserves more attention than a single row suggests, because it is exactly the line an exam scenario tests.",[22,613,615],{"id":614},"real-products-that-deliver-paas","Real products that deliver PaaS",[617,618,619,627,638],"ul",{},[620,621,622,626],"li",{},[623,624,625],"strong",{},"AWS Elastic Beanstalk:"," packages EC2 instances, a load balancer, and auto-scaling behind one deployment, still built on AWS's IaaS underneath, but you never touch those pieces directly",[620,628,629,632,633,637],{},[623,630,631],{},"Heroku:"," you run ",[634,635,636],"code",{},"git push heroku main",", and Heroku detects your language, installs dependencies, and deploys, with zero server configuration for standard frameworks",[620,639,640,643],{},[623,641,642],{},"Google App Engine and Azure App Service:"," the same trade, upload code, the platform runs it",[22,645,647],{"id":646},"worked-example-the-same-app-2-ways","Worked example: the same app, 2 ways",[27,649,650,651,653],{},"Shipping a small Ruby web app through EC2 means launching an instance, installing Ruby and its dependencies, configuring a web server, attaching a load balancer, and setting up an auto-scaling group, several separate steps, each one yours to get right and keep patched. Shipping the same app through Heroku means running ",[634,652,636],{},". Heroku reads the code, recognizes it needs a Ruby runtime, builds it, and starts serving traffic, all from that 1 command.",[27,655,656],{},"That is not a smaller version of the same job. It is a different job: you stopped managing infrastructure and started managing only your application.",[22,658,660],{"id":659},"the-misconception-paas-is-not-zero-infrastructure-decisions","The misconception: PaaS is not \"zero infrastructure decisions\"",[27,662,663],{},"It is tempting to assume PaaS removes infrastructure thinking completely. It does not. You still pick a dyno or instance size, still set environment variables, and still pay for the capacity you have allocated whether or not it is handling traffic right now, a Heroku dyno you provision keeps running, and keeps billing, until you scale it down yourself. A model that only charges for the moment your code actually executes is a different idea again, serverless computing, and this course covers it later in the Modern Cloud Architectures topic. PaaS narrows your infrastructure job. It does not delete it.",[22,665,667],{"id":666},"the-boundary-ahead-paas-versus-saas","The boundary ahead: PaaS versus SaaS",[27,669,670],{},"PaaS still asks you to write the application. That is the line the next lesson erases entirely.",[22,672,189],{"id":188},[27,674,675],{},"PaaS trades some of the control IaaS gave you for speed: you stop managing servers and start shipping code straight to a platform that runs it. The next lesson covers what happens when even the code is no longer yours to write.",{"title":194,"searchDepth":195,"depth":195,"links":677},[678,679,680,681,682,683,684,685],{"id":538,"depth":198,"text":539},{"id":32,"depth":198,"text":33},{"id":553,"depth":198,"text":554},{"id":614,"depth":198,"text":615},{"id":646,"depth":198,"text":647},{"id":659,"depth":198,"text":660},{"id":666,"depth":198,"text":667},{"id":188,"depth":198,"text":189},[],[528,529,530,531],{},"/courses/cloud-computing-fundamentals/en/domains/02-cloud-services-and-architecture/01-cloud-service-models/02-platform-as-a-service",{"passingScore":212,"questions":691},[692,698,702,709,716,724],{"question":693,"type":216,"options":694,"correctAnswer":62,"explanation":697},"A developer wants to deploy a web app without choosing an operating system, patching it, or configuring a web server manually. Which service model fits?",[59,695,62,696],"Traditional on-premises hosting","None of these","PaaS takes the operating system and runtime off the developer's plate, leaving only the application code and its configuration. IaaS still requires choosing and patching an OS, and traditional on-premises hosting requires even more of that work.",{"question":699,"type":216,"options":700,"correctAnswer":227,"explanation":701},"In Platform as a Service, the customer is still responsible for patching the operating system the application runs on.",[226,227],"PaaS is defined by the provider taking over the operating system and runtime, which is exactly what separates it from IaaS. The customer keeps control of the application code and its configuration, but OS patching moves to the provider.",{"question":703,"type":216,"options":704,"correctAnswer":517,"explanation":708},"Compared to IaaS, what does PaaS additionally take off the customer's plate?",[705,706,517,707],"Nothing, IaaS and PaaS manage identical layers","The physical network","Application code and data","The single row that moves between IaaS and PaaS is the operating system and runtime, both of which shift from the customer to the provider. Application code and data stay with the customer in both models.",{"question":710,"type":239,"options":711,"correctAnswers":714,"explanation":715},"Which of the following are PaaS products? (Select all that apply.)",[241,712,713,243],"AWS Elastic Beanstalk","Heroku",[712,713,243],"Elastic Beanstalk, Heroku, and Google App Engine all let you deploy code without managing the operating system underneath it, the defining PaaS trait. AWS EC2 hands you a virtual machine with the OS layer still yours to manage, which makes it IaaS instead.",{"question":717,"type":216,"options":718,"correctAnswer":722,"explanation":723},"A team deploys their app on Heroku and assumes they no longer pay for anything unless their app is actively serving a request. Why is this assumption wrong?",[719,720,721,722],"Heroku does not charge for dynos at all","Heroku is a SaaS product, not a PaaS product","PaaS only charges for storage, never for compute","A provisioned dyno keeps running, and billing, until you scale it down yourself, whether or not it is handling traffic","PaaS still requires choosing and paying for allocated capacity, a dyno or instance size, that keeps running and billing regardless of whether it is currently serving traffic. A model that only charges for the moment code actually executes is a different idea, serverless computing, covered later in this course.",{"question":725,"type":216,"options":726,"correctAnswer":727,"explanation":731},"Deploying an app via Heroku instead of directly via EC2 mainly changes which job the developer is doing. What is that change?",[727,728,729,730],"The developer stops managing infrastructure and manages only the application","The developer now manages the physical hardware instead of AWS","The developer takes on more responsibility for network security","There is no real change, the number of steps stays the same","Shipping through EC2 means installing a runtime, configuring a web server, and setting up a load balancer and auto-scaling group, several separate steps the developer owns. Shipping through Heroku collapses that into a single deploy command, because the developer's job has shifted from managing infrastructure to managing only the application.",{"title":524,"description":525},"courses/cloud-computing-fundamentals/en/domains/02-cloud-services-and-architecture/01-cloud-service-models/02-platform-as-a-service","ERzC9aKGOJ1IGuITkecV6OlXj68W2tYhsKzklnJiklM"]