IT Architecture Technical blueprint for evolving a corporate infrastructure resource that can be shared by many users and services processing systems hardware application software operating system telecommunications systems data architecture

Requirements of an Effective Architecture Provide as much vendor independence as possible Be able to integrate incompatible elements Incorporate standards either in use or likely to be adopted by leading vendors or electronic trading partners

Migrating from Mainframes to Client/Server Gradual migration by developing all new applications specifically for client/server environment moving user interfaces from mainframe to PC and communications management to servers

Migrating from Mainframes to Client/Server Gradual migration by (cont’d.) move applications to workstations or PCs and leave the mainframe as a database server move mainframe databases to smaller servers

Migrating from Mainframes to Client/Server Move as much processing as close as possible to the user Share as little as possible, e.g., only the data Build peer-to-peer networks Avoid migrating old code

Migrating from Mainframes to Client/Server Simplify the enterprise-wide computing environment Automate the management of the enterprise’s information architecture Write as little code as possible

Reasons to Replace Applications Code and documentation has suffered from years of changes and is now “fragile” Documentation is out of date Technology upgrade promises significant operating cost reduction

Reasons to Replace Applications Current technology platforms are difficult to maintain Business processes have been redesigned and new applications are required

Management Concerns About Replacement High potential investment required Lack of skill and experience with the new technology Lack of availability of packaged solutions that could reduce replacement costs

Management Concerns About Replacement Concerned that the need for replacement is technology-driven Risks of replacement

Typical Methods Used to Decide on Replacement Cost/benefit analysis that compares ongoing cost of maintenance and enhancement with the cost of replacement Payback analysis based on benefits that could be obtained with the new system

Typical Methods Used to Decide on Replacement Make-or-buy analysis that compares cost of new development with cost of acquiring and modifying a software package