1. MIGRATING TO CLOUD
Approach
SEPTEMBER 5, 2014

2. Cloud Migration Approach
Ver 1.0 P K Mallik Page 1 of 5
Contents
Introduction.................................................................................................................................2
Cloud Migration............................................................................................................................ 3
Suggested Approach..................................................................................................................... 4
Feasibility.................................................................................................................................4
Usage ...................................................................................................................................4
Commercialisation................................................................................................................. 4
Technology ........................................................................................................................... 4
Impact and Business Case..........................................................................................................4
Define Roadmap and implement ............................................................................................... 5
Proposition ...................................................................................... Error! Bookmark not defined.
Time Frames................................................................................. Error! Bookmark not defined.

3. Cloud Migration Approach
Ver 1.0 P K Mallik Page 2 of 5
Introduction
The Cloudmodel hasbeengainingmomentumasitisseenasprovidingsignificantadvantagesover
hostedservicesandin-house datacentres. These are mainlyinthe followingareas:
 Move fromCAPEXto OPEX
 Pay as yougo for servicesandcapacityutilisation
 QuickerProvisioningof Hardware andPlatform
 MeetFluctuatingDemandandUnpredictable Load
 Integration acrossdifferentservicesmade easy
 Upgrades are relativelyhassle free
Howeverthe cloudmodelsalsohave some significantdisadvantagesasfollows:
 Can leadto unexpectedlyhighchargesif administratorsdonotadaptto the cloudpricing
model
 Users wouldlose some control overITassets
 VendorLock-inislikelydue tothe differentwaysinwhichcloudisimplemented
 Notall software,versionsandtoolsare supported soacertainamount of re-engineeringand
feature degradationshouldbe expected
Some of the commoncloudmodelsare as follows:
 Software asa Service –SaaS – usedby
Microsoft,Apple,SAP
 Platformasa service –PaaS –
PopularisedbyAzure,Google
 Infrastructure asa service - IaaS– More
of a hostingservice positionedascloud.
PopularisedbyAmazon
 Others
• Hardware as a Service –HaaS –
Notreallycloud,oldleasing
model innewclothes
• Everythingasa Service – EaaS – nothingreally,couldfitbusinessprocess
outsourcing
Thisdocumentexaminesthe differentmodels,looksatmigrationapproachandsuggestsa way
forwardto implementcloudcomputingwithaview towardsaquickRoIand minimumrisk

4. Cloud Migration Approach
Ver 1.0 P K Mallik Page 3 of 5
Cloud Migration
While newapplicationscanbe designedtobe deployedonacloudarchitecture,migratingan
existingapplicationtoa cloudmodel canbe a trickyissue. The followingmodel outlinesthe different
strategieswhichmaybe adoptedbasedinthe targetcloudmodel:
Migrate to Approach Description
IAAS Port Whenmovingtoan infrastructure cloudthe applicationwould
mainlyneedportingwithsome minordesign andcode changes
PAAS Re-Architect It wouldbe necessarytore-architectapplicationsnotjusttoget
maximumbenefitsbutalsotoenable the applicationtoscale
and manage loadsonthe cloudplatform.
Re-architectingwouldalsoenable cloudbasedfeaturestobe
offeredasa service
SAAS Outsource Unlike productssoftware serviceofferingsare outsourcedto
thirdparty providers.
Where companiesare runningtheirownprivate cloudcertain
specialityservicesmaybe outsourcedasanextensionof the
private cloud

5. Cloud Migration Approach
Ver 1.0 P K Mallik Page 4 of 5
Suggested Approach
In orderto successfully migrateapplicationsontocloudenvironment,the followingthree step
approach maybe useful:
1. Determine the feasibilityof migrationtocloud
2. Identifythe impact,defineroadmapandbuildabusinesscase
3. Define roadmapandimplement
Feasibility
In orderto determine feasibilitythe targetapplicationwillneedtobe evaluatedalongthe following
parameters.
 Usage
 Commercialisation
 Technology
A typical feasibilitystudyandanalysiswouldtake between1to 2 weeks.
Usage
The usage identifiesthe nature of the usergroupwhichisusingthe application. Baseduponthe
usage there couldbe constraintsthatcan limitthe benefitsof acloudarchitecture assome cloud
featuresmayneedtobe dedicated.Some of these are summarisedinthe followingtable:
Usage Security H/W Software
Licenses
Application
s
Database Content Network Manpower
In House VPN Shared Shared Common Shared Shared Shared Shared
Private
Company
On
Demand
Shared Shared Common Dedicated Dedicated Shared Shared
Govt with
Citizen Data
Dedicated Dedicated Dedicated Dedicated Dedicated Dedicated Dedicated Dedicated
Govt Support
services
Shared Shared Shared Common Dedicated Dedicated Shared Shared
Commercialisation
The commercialisationdetailsthe commercial model whichwouldbe mostapplicable tothe
application.The followingare some of the more popularmodels:
 Subscriptionbasedata fixedcostpermonth/year
 Pertransaction
 Resourcesconsumed(CPU,Memory,Disk,Network)
As part of the feasibilityitwouldbe necessarytodetermine if the proposedcommercial model
wouldbe acceptable
Technology
Technologywouldbe acritical determinantof the migrationasthe suitable target platformwould
needtobe capable of deliveringthe existingfeatureswiththe minimumof disruption
Impactand BusinessCase
In orderto arrive at a businesscase animpactanalysiswouldneedtobe done basedonthe existing
platformandthe target. The analysiswouldneedtoidentifythe variousoptionsandrecommendthe

6. Cloud Migration Approach
Ver 1.0 P K Mallik Page 5 of 5
preferredone basedoncostand risk.Some of the parametersonwhichthe impact analysiswill be
done wouldbe:
 Applicationchangesanddevelopmentcost
 Performance
 Security
 Feature degradation
Basedon thisand the targetcloudenvironmentthe costof migrationandownershipwouldbe
determined. Variouscloudcalculatorsare availablewhichcanhelpdeterminethe costs.
Basedon the commercializationmodelthe returns/savingscanbe workedoutand thiswouldhelp
create the businesscase.
Define Roadmapand implement
Once the businesscase hasbeenacceptedkeymilestone datesneedtobe definedfordifferent
aspectsof the implementation.Thesewouldinclude:
 Hardware and network(forprivate cloud) configuration
 Cloudservice providerselection(forpublicclouds)
 Applicationmigration(dependinguponthe targetmodel)
 Data migration
 Contentmigration
 Adminandsupportsetup
 Cloudinstrumentationsetup