Get the book "On the Portability of Applications in Platform as a Service" at https://www.amazon.de/dp/3863096312 Presentation from IEEE SOSE 2014. Full paper at http://bit.ly/paaspaper

1. Towards Application Portability in
Platform as a Service
Stefan Kolb and Guido Wirtz
Distributed Systems Group
University of Bamberg, Germany

2. Application
PaaS Cloud
Platform as a Service
You get an application
You get an application environment
You get a virtual machine
You manage everything
IaaS
PaaS
SaaS
Traditional IT
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Cloud

3. Value proposition
Hosted Environment
+ Less configuration
+ No hassle with complex distributed systems
+ Instantly become productive
Pay for what you need
+ Transparently scale from one to thousands of
customers
+ IT dynamically grows with your business
 Focus on your applications
 Save money
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4. Lock-in prevents portability
Different notions of PaaS
– No real model of current PaaS
– No single comparable set of offerings
Heterogeneity between vendors
– Platform components & capabilities
– Platform restrictions
– Still no one-size-fits-all!
 Lock-in
 Potentially high switching costs
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5. Our approaches to these issues
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Literature
review
Analysis of 76
PaaS vendors
PaaS Model
Feasibility
Use Case
Different
notions of
PaaS
Heterogeneity
between
vendors
Extract
comparable
components &
capabilities
Application
Portability
Matchmaking
PaaS Profiles

6. PaaS categories
Comparable application platform & building blocks
Extension platforms,
visual tooling
Composition of
low-level Services
Classical app
environment
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7. PaaS model
Current PaaS ⊆ Model
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8. The abstraction of the physical infrastructure or IaaS capabilities.
Infrastructure layer
Instance
Memory CPU Share Disk
Geographical
Regions
Deployment
Models Scalability
Horizontal scalingImportant for end user locations
(latency, legal reasons)
Public vs. private
Hosting Vertical scaling
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9. Platform layer
Runtime Stack
Middleware
Service Stack
APIs
Bindings
Native
Services
Add-on
Services
Frameworks
Buildpacks
Apps
Languages
The service and library interfaces to which the application is written.
 Application dependency portability
Third-party providers,
SSO, provisioned
through PaaS API
Co-located,
operated by the
PaaS provider
Boundary to IaaS
Extensibility mechanisms for installing missing runtime or service components
Including
proprietary,
platform-specific
APIs
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10. Management layer
Application Administration
ProvisioningDeployment
Platform Administration
ScalingMonitoringAuthentication LoggingBilling ……
PaaS user manages their use of the platform.
Application
life cycle
Services
& Add-ons
Accessible via Web-UI, CLI or REST-API
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11. How can we tackle portability threats?
Standardization
– Portability of applications
• Single unit of delivery including all dependencies
• e.g. Docker containers, TOSCA
– Portability of application dependencies
• e.g. standardized buildpacks
 Lack of acceptance by industry leaders prevents adoption
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12. How can we tackle portability threats?
 Rely on native support and open technologies
+ No intermediaries, instant applicability!
+ There are common setups that are often used by
developers
+ Vendors want to attract many customers, so the
environmental setups should intersect
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13. A no-standards approach for
application portability
If all components and capabilities are supported, we should be
able to run our application – additional work expected.
CB
A
2. Where can I port
my application?
 Match application
requirements with
vendor capabilities
1. What are the
most important
components &
capabilities I need
to match?
 PaaS model
Non portable
Vendor A
Vendor B Vendor C
Partially
portable
Portable
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14. Profile Taxonomy
Components & Capabilities
• Runtimes
• Frameworks
• Middleware
• Services
• Extensibility
• Hosting
• Scaling
• Infrastructures
Business Aspects
• Status
• Pricing
• Compliance
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15. PaaS Profiles
• Machine-readable representation of the taxonomy
• Profiles serve as description language and catalog for inter-cloud
resource discovery
By means of this discovery we can identify high-level portability for:
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Deployment on a single PaaS
Migration from on
premise to PaaS
Migration between
different PaaS
Identify portable building blocks for PaaS applications
High-level
Portability

16. 17
+ Currently 76 active vendor profiles
+ Open source including vendor verification
 Most recent and comprehensive data set available

17. Application Portability Matchmaking
User-defined: Visual selection to satisfy business user
Application Profile: Enable automated discovery
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Application Requirements

18. Application Portability Matchmaking
Web Application
Try it!
https://PaaSfinder.org
https://github.com/stefan-kolb/paas-profiles
Web UI
JSON API
76 profiles
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19. Feasibility Use Case
Ruby MongoDB as a Service
Application Profile ⊆ PaaS Profile
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20. What and how much work do I need to put into my deployment
workflow and application code?
How difficult is the migration?
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 We can port the application with reasonable effort
 We need to investigate more on the amount of low-
level problems for larger projects

21. Future Work
Partial Matching Algorithm
● Replacability of components by add-ons (e.g. data stores)
or buildpacks (e.g. runtimes)
Migration Effort
● Currently working on a real-world scenario with a start-up
company
Management API Portability
● Similar functionality, but very different workflows &
commands
Implementation & Environmental Differences
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22. Thank you!
Questions?!
Stefan Kolb
@stfnklb
https://PaaSfinder.org
stefan.kolb@uni-bamberg.de
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