1) The document describes a PaaS system called PaaSSOA that was deployed on Amazon Web Services (AWS) to test its ability to operate on a real IaaS. 2) Key aspects of PaaSSOA that were tested include its scalability using AWS services like SNS for communication and ELB for load balancing. Logging and monitoring were implemented using MongoDB and Node.js. 3) The results confirmed that PaaSSOA can successfully run on AWS and demonstrated the importance of mediation between the PaaS and IaaS layers. This validates the concept of an enriched service-oriented architecture that better embraces cloud paradigms like elasticity.

1. PaaSSOA AWSValentino Baraldo
Laurea Magistrale Informatica
Università degli Studi di Padova
A SOA-based PaaS
over Amazon Web Services
PaaSSOA on AWS

2. Outline
● SPI stack
● SOA Concepts
● PaaSSOA
● The aim of my work
● AWS PaaSSOA Connector
● High level architecture
● Logging and dashboard
● Concrete results
● Abstract results
● Future prospects
Problem def. & Solution space - Proposed solution - Results & future prospects - 2/18
}
}
}
Problem definition and
solution space
Proposed solution
Results and future prospects

3. SPI Stack
Infrastructure as a Service
Software as a Service
Platform as a Service
SPI Stack
Problem def. & Solution space - Proposed solution - Results & future prospects - 3/18

4. Service Orientation
Concepts
Design principles
■ Standardized Service Contract
■ Service Loose Coupling
■ Service Abstraction
■ Service Reusability
■ Service Autonomy
■ Service Statelessness
■ Service Discoverability
■ Service Composability
Problem def. & Solution space - Proposed solution - Results & future prospects - 4/18

5. The current state of
PaaSSOA
IaaS Stub
SaaS Stub
PaaSSOA
Central (Manager,
Registry, Monitor)
SOABoot
S S S
SOABoot
S S S
...
<push events>
<start> <stop>
<deploy> ...
Action Iface Logger Iface
Rule engine
Web
monitor
Browser
Problem def. & Solution space - Proposed solution - Results & future prospects - 5/18

6. The aim of my work
● Testing PaaSSOA on a real IaaS
○ How can we imagine a real agnostic PaaS?
○ Can a PaaS tier create tangible value in the SPI stack?
● Can the PaaSSOA concept and technology stack
reside on a real-world IaaS such as AWS?
○ Scalability (and elasticity) should be our best friends from the
beginning!
○ Many interesting open engineering challenges
● Understand how SOA should evolve to embrace
cloud computing paradigm better
Problem def. & Solution space - Proposed solution - Results & future prospects - 6/18

7. AWS PaaSSOA Connector
PaaSSOA Central Main Monitor Service
SOABoot
JavaService
IaaS Iface
JavaService JavaService
IaaS Iface IaaS Iface
IaaSConnector
● How have we built this connector?
○ Interfaces as agnostic layer, in a federated
scenario there are heterogeneous IaaS providers
○ A small Java service for every component that
talks with the AWS APIs
Problem def. & Solution space - Proposed solution - Results & future prospects - 7/18

8. Scalability challenges
Central
SOABoot
S S S
SOABoot
S S S
<publish events>
Action Iface
Rule engine
P
u
b
/
S
u
b
PaaSSOA
● Not only push model but
also strict decoupling
○ PubSub Broker (IaaS)
● Publish all events?
○ Policies and
mechanisms to control
event production
● Removed the single
receiver constraint
Problem def. & Solution space - Proposed solution - Results & future prospects - 8/18

9. AWS Architecture
AWS VPC
SOABoot VM
S
Central
VM
SOABoot VM
S
SOABoot VM
S
AWS
ELB
Requests Gen
VM
Requests Gen
VM
public endpoint
private subnet
A
W
S
S
N
S
● Env boundaries
○ Private subnet AWS
VPC
● Communication
○ AWS SNS
● Load balancing
○ AWS ELB
○ (2-levels dispaching)
Problem def. & Solution space - Proposed solution - Results & future prospects - 9/18

10. Logging and dashboard
challenges (1/2)
● Different consumer have different needs
○ For reasoning we need a fresh and preaggregated stream
○ For logging we need a continuous stream
● Bottlenecks assured with centralization
○ Local solutions are the right way!
○ Eventual local preaggregation of events
○ Every VM and service writes logs directly in a scalable service
● The user monitor can become a dashboard
○ An expression of a PaaS abstraction layer
○ An expression of the mediation of interests role
○ Full push architecture -> real-time charts and tables
Problem def. & Solution space - Proposed solution - Results & future prospects - 10/18

11. Logging and dashboard
challenges (2/2)
● MongoDB as log DB
○ Very fast
○ Scalable with sharding
○ Tailable cursor
● Real-time dashboard with
Node.js
○ Very fast
○ Full async architecture
○ Client push with
Socket.io
Problem def. & Solution space - Proposed solution - Results & future prospects - 11/18

12. Dashboard preview
Problem def. & Solution space - Proposed solution - Results & future prospects - 12/18

13. Results
● Showed that PaaSSOA can
reside on a real IaaS such as
Amazon Web Services
● Confirmed the importance of a
mediation of interests role
for a PaaS layer
● Proposed a new enriched
service oriented paradigm
that embrace better cloud
paradigm
Problem def. & Solution space - Proposed solution - Results & future prospects - 13/18
Amazon Web Services
PaaSSOA
AWSConnector
Reasoning
System
Monitor
SaaS
services
SaaS
services
SaaS
services
...

14. Abstract results (1/3)
● SOA and cloud computing are strictly related
○ Many common principles
● However SOA could embrace better cloud paradigm
○ There is no clear notion of elasticity
○ Moreover an abstraction layer needs to be
prefixed to the elastic battery of service instances
Problem def. & Solution space - Proposed solution - Results & future prospects - 14/18

15. Abstract results (2/3)
● A new enriched service architecture
○ Many service instances and a request dispatcher
○ We want to express elasticity in the SOA paradigm
○ PaaSSOA AWS is a confirmation of applicability
Problem def. & Solution space - Proposed solution - Results & future prospects - 15/18

16. Abstract results (3/3)
● We also need of an abstraction layer
○ User has to perceive the system as a single and
uniform rather than composed by many single
nodes
○ The dashboard as a valid manifestation of that
Problem def. & Solution space - Proposed solution - Results & future prospects - 16/18

17. Future prospects (1/2)
● Better reasoning strategies
○ With a decoupled system we can use different
reasoning components
○ Cost-based reasoning
● Develop other IaaS Connectors
○ OpenStack
● Federation with other PaaS layer
○ With different and heterogeneous IaaS
Problem def. & Solution space - Proposed solution - Results & future prospects - 17/18

18. Future prospects (2/2)
● Future scenario: federated PaaS
Problem def. & Solution space - Proposed solution - Results & future prospects - 18/18