Sunday, September 9, 2012

PLM Migration : Part 1

One of the most challenging aspect  in PLM field  is data migration. It not only required metadata migration but also vault files system specially CAD files and this create higher degree of complexitiy. Not only it required to make sure that all object and relation are migrated correctly but also sanity of interpart relation related to CAD should also maintain. In this blog I will discuss the factor required to be consider for PLM migration. Since migration it big topic, hence I will split the contain in to two parts.  
Migration Consideration:
Following are the important steps  for PLM Migration
·         What to Migrate
·         How to Migrate
·         Before you start
·         Design Approach
·         CAD Migration
·         CAD vs Meta Data Migration.
What to Migrate:
For any migration you have to know what required to be migrated. In PLM migration there will three aspect of migration
1)      Meta Data Migration
2)      Document File Migration
3)      CAD Migration
Meta Data Migration is migration of data stored in DB from one system to other. Where Document migration of actual files which is maintain by one system to other. CAD migration e
From system migration perspective it can be either of this
1)      Single System migration i.e from one system to other system migration
2)      Multi System migration. It can either of
a.       Multiple to Single System Migration.
b.       Multiple System to Multiple System.
For complexitiy perpective Multiple System to Multiple System will be most complex. But they are usually break down to various project to make them Multiple to Single System migration.
To define what to migrate we have to do first have good understanding of old and new system. Also required to have understanding of Buisness process. As in many cases moving to new system also involved change in Buisness process to leverage the advance functionality of new system. Hence proper analysis required to be done for Old vs New process as well GAP analysis for finding any short coming in new system functionality.
Once the above analysis is done then it come what data required to be migrated. In all cases metadata mapping  play prominent role as they represent real mapping of Buisness process to Object. Following aspect of Metadata mapping has to understand properly.
1)      What are Buisness object from present system are required to migrated to new system.
2)      What are the property of Buisness object required to be Migrated.
3)       What relation between objects  is there in old vs new system
Object Mapping is most important aspect of migration. Success of any migration will depend on effectively and correctly the mapping is done. Mapping with will be usually boil down one of this scenario.
1)      One to One Mapping : One object map to similar object in new system.
 Ex Part to Part migration
2)      One to Many Mapping : One object map to many object in new system:
 Ex SAP Routing can map to Item and Item Revision.
3)      Many to One Mapping : Many object map to one object in new system.
 Ex: Two Object with relation object merge to single object in new system.
4)      Property to Object Mapping : Any Property in old system will map to Business object in new system.
Ex : Work Area property of Routing Operation in SAP map to Workcell Item in Teamcenter.
Next step for migration is related to approach to Migration
 How to Migrate:
Once the What context of Migration is clear, then come How. The approach is defined by considering many factory. Factor can be categorize in following points
1)      Bulk vs Phase wise migration
2)      Custom Migration vs Thrid Party MigrationTools.
Bulk vs Phase wise migration : Bulk migration involve full migration in one go. Following are the characterictic of Bulk Migration
ü  Complete movement of all data to new system at once.
ü  All users switch over at the same time.
ü  All processes move to New System at once.
ü  Source system should not be modified after migration (read only)
Phase wise Migration : This involved migrating phase wise in a specific duration may be few months to few years.  This required to have both old and new system to be co-existing  for whole migration duration. Also may required to have sync interface between old and new system during migration period. Following are the charactertic of Phase wise Migration
    • Movement of specific data to new system based on certain criteria. Ex Group wise, project wise, workflow based etc.
    • Set of users switch over the time.
    • Co-existence of old and new system for some duration (From months to a year or so).
Bulk Migration
Phase Migration
Lower overall costs
Overall Higher Cost as two system required to maintain
No synchronization required between multiple legacy and new system
Synchronization required between old and new system
Change Management  and Training challenge is high.
Better Change and Training Management due to Phase wise migration
High impact in case of Migration failure.
Roll back can be easily done as old system coexist with new system
Suitable for Simple to Medium Complex Data. Also simple CAD with few BOM Line and depth
Suitable for Complex data mode and huge CAD assembly.

Custom Migration vs Thrid Party Migration: Second decision point is too made on Migration tools. Basically Migration tools can be either Custom Tools required specifically for migration or Vendor Tools. Most of Vendors provide offer Out of Self tools to migrate in their native system. For example Siemens PLM offer GMS for migration from Legacy system to Tc UA. Similarly other PLM Vendor provides similar tools. Analysis required to be done whether those tools are suitable for migration use case or not.  It is observed that PLM vendor usually claim to cover all use cases but in reality there GAP. This is truer if new PLM system has own migration tool.  This can lead to have more effort and cost then having custom approach.
Custom Migration approach is more suited if migration is from multiple system and data model is complex. Custom Migration gives more flexibility and control in migration. But at the same time it requires more effort and upfront cost for development and regressive testing. Most of time Custom Approach is done through ETL (Extract, Transform and Load) process where transformation is done in staging database. Following are the characteristic of both approach.

Custom Migration Approach
Third Party Tool Migration
Higher Upfront Cost
Only License cost involved
Suitable for Multi System Complete Migration
Suitable for simple migration supported tool
Regressive testing required
Limited testing required as it certified by provider.
Flexibility in case change in Business cases
Can be costly and time consuming if the Tool doesn’t support those use cases

Custom Migration approach also not really means developing everything from scratch. Most of time custom solution also involved using out of box utility provide by PLM system. Usually wrapper is written on top of them to make seamless migration. For example migrating CAD data always involves Vendor provided import/export tool which required to in sync with Meta data which can done through custom tools.
Before you start:
Before we start actual migration design it most important to have following aspect should be closed.
1)      Data mapping is completed.
2)       Also all Gap analysis and accordingly approach should be finalize.
3)      Expected Duration of actual Migration and delta approach.
4)      Infrastructure requirement mainly Server Capacity, Space etc.
We already discuss about Data Mapping and Migration Approach. It is also important to plan for expected duration because that will also defined strategy for delta consideration during migration process. Delta means all changes done between actual migration start and completion in native system. Since user can start working in new system only when the whole migration is completed, it is import to bring transition changes also in new system. This is done through Delta Migration planning. Delta migration comes in to picture when the migration is expected to take more few days and changes can moved from old to new system manually.
Infrastructure requirement is also important factory as it required considerable planning. Typically infrastructure requirement is calculated based on amount metadata as well volume required to be migrated.
This closes the first part of PLM migration blog. In this we discuss about factor required to be consider for migration. In the next blog we will discuss about Design and CAD aspect of migration.

See also :

PLM Migration : Part 2

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