1. Clouds Hands On
Tutorial
Srinath Perera Ph.D.
Senior Software Architect, WSO2 Inc.
Member, Apache Software Foundation
Visiting Faculty, University of Moratuwa
Research Scientist, Lanka Software
Foundation

2. Outline
• What is Cloud
Computing?
• What can I do with
the Cloud?
• How to do it?
• Conclusion
photo by John Trainoron Flickr http://www.flickr.com/photos/trainor/2902023575/, Licensed under CC

3. Quick EC2 Demo
• Lets us start our own Virtual machines in the
cloud.
• We call the virtual machines, AMIs (Amazon
machine images)
• You can reuse other’s AMIs or create your
own.

4. What is Cloud?
• Based on the idea that
computation and storage can
be rented as a utility from data
centers that runs somewhere
(in the cloud) on demand.
• Remote resources that are
rented
– On demand and in elastic
manner
– Pay as you go

5. Men, it has been well said, think in herds; it will
be seen that they go mad in herds, while they
only recover their senses slowly, and one by
one. ~ Charles Mackay
Copied from http://www.flickr.com/photos/54555810@N00/2848637190/, by Rambling Traveler

6. Gold Rush
• Very good example of a hype
• Only few actually made money
• But associated services (merchants and
transportations) made lot of money

7. The Cloud Bandwagon
• Is Cloud a hype? Of
course it is!
• Is it Just hype? may be
not, thats what we will
discuss.
• But don’t get me wrong,
• even if it is a hype, that
doesn’t mean we should
Image from
not be talking about it.
http://www.flickr.com/photos/88929764@N00/443
6978855/

8. Is Cloud Hype?
• We have to understand what it is and what
drives it? That would tell us how to navigation

9. Electricity as a Utility as an
Example
• Now, no one run generators themselves
• Use electricity that is remotely generated
• Can draw when need it
• Only pay for what you use

10. Electricity as a Utility: Benefits
• Small startup cost (do not
have to buy a generator)
• No operational cost
• Do not need to do
capacity planning
• Overall cheaper electricity
due to economics of scale
• Making it parts of the
everyday life, commodity
(accessibility)
Image from http://www.flickr.com/photos/infomofo/3220498521

11. Benefits of Cloud Computing
• Avoid/reduce operational
• costs by outsourcing
• Can scale up and down as
needed
• Pay as you go
• Making it parts of the
everyday life,
commodity(accessibility)
• Cheaper computing power
due to economy of scale

12. Drivers of Cloud
• Unused computing power
at Google, Amazon
• Max load >> average load
• High operational cost,
need for outsourcing
• Availability of large scale
solutions and
infrastructure as side
efforts of high tech
company operations

13. Cloud Classification

14. Cloud Platform Tradeoffs

15. Private Cloud
• Run a Cloud within the
organization (mainly due to
security concerns).
• e.g. Amazon Virtual Private Cloud (VPC), IBM private
cloud, WSO2 Stratos private Cloud
• Idea is optimizing resource sharing, utilizations, and
operations
– e.g. testing environments
• Connection to public Cloud is possible (e.g. Amazon VPC
uses VPN) Image http://www.flickr.com/photos/glasgows/536185797/, Some rights reserved by M Glasgow

16. Cloud Computing Models
Control
Flexibility of Purpose
Level of Abstraction
Software as a Service
Platform as a Service
Infrastructure as a Service
Public Hybrid Private
Economy

17. What can we do with
the Cloud?

18. What Can We do with the Cloud?
• If I am a developer, now it is
– Easy to get access to a machine
– Easy to host something
• If I am a startup
– Easy run my new business
– Easy to run my app
• If I am a Enterprise
– Outsource functionalities
– On demand H/W
• If I am a researcher
– Easy access computing power

19. More Room to Outsource Non
Key Functions of a Organization
• Organizations outsource their non-
competitive areas to reduce costs
and focus on their own expertise.
• IT departments are a major cost in
most organizations
• Cloud enables Organizations to
outsource some of the IT functions

20. Small Start Up Cost
• Small start up cost
• Reducing the gap between
visionaries and dreamers
• New organization has better
chance for outsourcing
operations through the Cloud
• Cloud competition likely to
drive down hosting prizes

21. 1 computer for 100days = 100
computers for 1 day
• Great tool for occasional
computations
– Research labs
• Reporting collecting data for
a story
– New york Times tiff to pdf
conversion
• Rise of analytics
– great tool for offline analysis
– Business Intelligence (BI)
– Audits

22. Increased Accessibility
• Large Scale Computation and
Storage Resources becoming
a Commodity
• Computer intensive desktop
apps (e.g. Excel, 3D Max)
• Normal people, not just
organizations can have
access to computing power
and storage

23. Creating and Deploying my Sample
App in the Cloud

24. Explain the Scenario
• Web App
• A Web Service
• Web App call the Web Service and show a
hello world message got from Web Service.

25. Demo It Locally
• Install WSAS
• Show consoles
• Install the Service
• Try the Service
• Install the Web App
• Try the Web app
• Show SOAP traces

26. IaaS (Infrastructure As a Service)
• Let users allocate and use a computer on-
demand, and can be returned when not
needed.
• Once allocated, node behaves as a normal
node.
• None or minimal add-on services

27. E.g. Amazon Web Services
• Several Services
– S3 Storage
– EC2 computing cloud
• Based on Virtualization, where each user is given a
virtual machine and charged by the hour
• Need least amount of changes to move apps to the
Cloud. They in a way replace hosting services
• Least amount of out of the box services (e.g. DOS
attack prevention) and advanced services like scaling
etc., are a responsibility of the user.
• Often the best choice for ad-hoc computer users.

28. Demo 1
• Login to the AMI
• Download WSAS and install
• Login and show the console
• Upload the Service
• Tryout the service
• Upload the Webapp
• Tryout the Web App
• Show SOAP traces

29. Demo 2
• However, if we shutdown the Instance, all is
lost
• Create and save the AMI
• Restart and show

30. Enabling Technology: Virtualization
• IaaS uses Virtualization to provide
infrastructure as a service
• Virtualization can add significant
overhead (each instruction
become 2 instructions)
• New CPUs have hardware support
for virtualization,
– which make things better
– still I/O is a challenge

31. Pros & Cons
• Very easy to start
• Minimal changes to the App
• But not many add on features
• Lack of persistence make life tricky

32. PaaS (Platform as a Service)
• It provide servers (middleware platforms) as a
service
• Can deploy your application artifacts in the
cloud
• Unlike IaaS, it can give you add on services.
But it will only support specific application
types.

33. Why PaaS?
• IaaS only provides limited saving to someone
who needs to outsource their IT functions
• SaaS is great when they can be used
• They are usually very specific (e.g. email, CRM ..)
• If they match, then great, but if they are not, not
much choice for the user.
• PaaS stays in the middle ground
• Framework to host your apps
• Hopefully you can move your apps as it is (well not
the case with Azure or App Engine, but it is possible
with WSO2 Stratos !!!).

34. Google App Engine
• Support Java and Python
• Support web requests and run user written
web applications in an isolated environment
• Java version is based on servlets
• Support storage based on Big table,
memcache based cache, and auto scaling
• Can write apps locally, test it, and then upload
to the Cloud

35. WSO2 Stratos
• Support Java based SOA artifacts (services,
workflows, mediation) , messaging, CEP, Rules,
etc
• Support running user written web applications in
an isolated environment
• Built on Open source projects like Axis2, ODE etc
• Support storage based on MySQL, Cassandra, and
HDFS
• Can write apps locally, test it, and then upload to
the Cloud

36. Show Stratos
• Create an Account
• Compare with Local Server

37. Stratos Demo
• Upload the Service
• Try out the Service
• Show with SOAP Tracer
• Upload the Web App
• Try out the Web App
• Enable Security

38. Add-On the Features
• Edit Web app security
• Mediate requests
• Add Throttling
• Add Caching
• Create and use Data sources

39. Driving Technology: Multi-tenancy
 Many Parties share the same set of resources,
while giving each one his own space

40. Why Multi-tenancy? 1. Increased
sharing
• Cloud shares
resources across a
large pool of users.
• Now sharing
happens in the
application level as “There is no delight in owning
oppose to sharing at anything unshared.”
OS level for multiple Seneca (Roman philosopher, mid-1st century
processes and AD)
sharing at HW level
with VMs.
photo by Ben Gray on Flickr, http://www.flickr.com/photos/ben_grey/4582294721/,
• That can bring Licensed under CC
greater savings

41. Why Multi-tenancy? 2. Provide “pay
for what you use”
• Often there will be many accounts in
a PaaS or a SaaS, but only a fraction
of them will be in use.
• We cannot allocate runtime resource
per account (disk may be ok, as it is
cheap). For example, we cannot run
a VM per account.
• By sharing the same server with
many users, Multi-tenancy provides
much reduced runtime cost per
server.

42. Multi-tenancy vs. Virtual Machines
• Multi-tenancy provides much fine
grained sharing by many applications
sharing the same server.
• Say there are 100k accounts, but 10k
active users at a time. VM based
model needs 100k VMs, which
means there is a cost incurred per
account.
• With Multi-tenancy one server can handle many accounts, and by
mixing and matching heavy and light users, Multi-tenancy can
operate with much less number of servers.
photo by hans s on Flickr, http://www.flickr.com/photos/archeon/2359334908/

43. Cloud Native
• Elastic (Uses the cloud efficiently)
• Scales up and down as needed
• Works with the underlying IaaS
• Self-service (in the hands of users)
• De-centralized creation and management of tenants
• Automated Governance across tenants
• Multi-tenant (Only costs when you use it)
• Virtual isolated instances with near zero incremental cost
• Implies you have a proper identity model
• Granularly Billed and Metered (pay for just what you use)
• Allocate costs to exactly who uses them
• Distributed/Dynamically Wired (works properly in the cloud)
• Supports deploying in a dynamically sized cluster
• Finds services across applications even when they move
• Incrementally Deployed and Tested (seamless live upgrades)
• Supports continuous update, side-by-side operation, in-place testing and
incremental production

44. Cloud Native Middleware

45. Auto scaling by Tenant Aware Load
Balancing

46. Software as a Service
• Provide a complete package as a service
• Very easy to get started
• Generally only provide limited customizability
• Might provide higher level domain specific
abstractions and functionality

47. SaaS Example: Salesforce
• Provide support for CRM (Customer
Relationship Management) software as a
Service
• The application available out of the box users
• just configure and use it.
• Salesforce handles all the details, and a ideal
choice for outsourcing IT functions
• However, applications are very specific and
customizations are limited.

48. SaaS App Market
• Mobile apps, Browser Apps etc often depends
on backend, that need to be hosted and
running.
• Also, there is the old user case of service
market place (e.g. Map Service, targeted
advertising suggestions)
• PaaS could provide an ideal environment to
develop and run them.

49. Cloud Platform Tradeoffs

50. Wrapping Up

51. Latency/ Bandwidth
• Why does electricity as a Utility
was so successful? One key
aspect was almost unlimited
speed and capacity
• Is that the same for Cloud?
– Not really
– Most people dismiss this, and
does not even want to discuss
– But for some apps (e.g.
interactive apps like games) this
can be a issue
• Possibilities
– support for offline operation
– Fedex your data

52. Autoscaling and Cloud Bursting
• Max load >> average load
• Allocate based on the load
• Running internal machines in an average load
(because cloud is still expensive than hardware ) and
• Scale out to cloud when there is high load
• Mimic the Hybrid car

53. Performance
• In the Cloud, your software will run on an another layer of
abstractions
• It will inevitably slower (3-4 times if unlucky)
– Often the overhead comes from I/O
– Some hit on CPU power
• Expect the bottlenecks to shift
• Remember performance ≠ scalability
• Cloud likely to let you scale out, but performance on
individual nodes likely to go down

54. Service Performance

55. Security
• With cloud you will run your apps and put your
data in an outsider's administrative domain, Can
we trust the outsiders to not look at our data?
– Well it depends. But concern is normal for any out
sourcing
• Can we trust their security measures? Does the
isolations are good enough?
• If we are keeping data owned by others, what are
the legal implications etc.

56. Look back: Recommendations
• How can we benefits from the Cloud? My list of benefits
were by no means exhaustive.
– If you are small startup? Doing something part time (writing
Apps for App Store), then cloud is for you definitely.
– If you have a small data center, need to efficiently manage that
and increase utilization, you should think Private Cloud
Copyright Kirsty Smith and licensed for reuse under this Creative Commons
License

57. Look back: Recommendations (Contd.)
• If your services have a Max load >> Average load, you
should think about crowd bursting
• If you do heavy computations once in a while
(analytics, audits), then use IaaS there.
• If you want to outsource some of your IT functions,
think SaaS
• Before leap think about 3 major concerns of Cloud?
– Security/ Privacy, Latency and Performance
• How much sharing and savings I need?
– IaaS, PaaS, SaaS

58. Overall Recommendations

59. Questions?
Copyright by romainguy, and licensed for reuse under CC License
http://www.flickr.com/photos/romainguy/249370084