Integration Technologies and InfrastructureBy Garrett Kelly

3 types or reasons for distributed applicationsData

Data used by the application is distributedComputation

Computation is distributedUsers

Users of the application are distributed

Why is Computing Distributed? Data

Applications must execute on multiple computers because the data that the application must access exist on multiple computers Both Administrative and ownership reasons Permissions must be granted

Accessed remotely but not stored locally

Why is Computing Distributed? Computation

Some applications execute on multiple computers in order to take advantage of multiple processors computing in parallel to solve problems Examples: Folding at home and also many math

institutions hoping to solve equations Pyramid Scheme

Distributed applications can take advantage of the scalability and heterogeneity of the distributed system

Why is Computing Distributed?Users

Many applications execute on multiple computers because users of the application communicate and interact with each other via the application

Fundamental Realities of Distributed SystemsCo-Located (Local Systems)

Communication = FastFailures = Objects fail togetherConcurrent Access = Only with multiple threadsSecure = Yes

DistributedCommunication = SlowFailures = Objects fail separatelyConcurrent Access = YesSecure = No

What is CORBA? Why is it important?CORBA, or Common Object Request Broker

Architecture, is a standard architecture for distributed object systems. It allows a distributed, heterogeneous collection of objects to interoperateCORBA is a specification, a guide for implementing

productsImportance

One of the goals of the CORBA specification is that clients and object implementations are portable

Code written for one vendor’s CORBA product could, with a minimum of effort, be rewritten to work with another vendor’s product.

What is COM, and how does it work in principle?A software architecture that allows

applications to be built from binary software components

Yes it does work in principalCOM is the underlying architecture that forms

the foundation for higher-level software services

Comparison between CORBA and COMBoth are architectures or specifications on

how to implement a software project to successfully create a distributed architecture.

CORBA is a framework, and COM is the architecture

Questions?