F7 Flashcards
What is SoSI?
Service oriented System Integration
Allows enterprises to through services share the
functionality of distributed software applications
What is the advantages/disadvantages of SoSI?
Advantages:
- Standardized functional
interface description, i.e.
language and platform independent.
- Scalability by the use of the ESB
integration middleware.
Disadvantages:
- Legacy systems have to be
adapted to support service-
oriented SI. Legacy (aka
“existing”)
applications are those that have
been inherited from languages
and platforms earlier than a
current technology.
- Bigger integration effort than
when integration (only)
information.
What is SOA?
Service Oriented Architecture
Is an architectural approach for designing/building canonical software service-oriented systems from reusable units called services that can communicate using standardized protocol over a network.
What is the 5 SOA design principles?
Contracts:
- Ensure a consistent expression of service capabilities and its overall purpose (i.e. functions,
“vocabulary”, the context of use / policies, etc.)
Discoverability:
- A means for consistently communicating information about services using a central place (repository)
Loose Coupling:
- Reducing (minimizing) dependencies between services, service contracts and implementation, contracts and consumers, etc
Statelessness:
- Optimize service processing logic from the time perspective – to support the requirements of
multiple consumers, while the service itself consumes as little resources as possible. A solution:
keep states in databases or in processes.
Composability:
- Enable service capabilities to be repeatedly combined with those of other crevices.
What is Point-To-Point integration?
Integration between service providers and consumers
using the point-to-point connection.
What is ESB?
Enterprise Service Bus
Its a middleware logic that enables to connect a large number of service-based software applications without a need for each pair of the applications to make a direct (i.e point to point) connection
(Sometimes called Service Integration Broker)
What kind of integration problems does ESB solve?
Scalability - by the multi-point connection, and routing
Heterogeneity - by protocol and message transformation
Does ESB support a synchronous or asynchronous integration?
Both!
Synchronous via DO/ORB and asynchronous via MOM logic
Can you explain the ESB integration solution?
The applications do not interact directly with each other;
instead, the applications connect to a bus and the bus provides the means for indirectly connecting the applications.
What is the benefits of ESB?
The number of connections is equal to the number of integrated applications.
The maintenance and upgrade are easier, such as the removal of an application.
Loose-coupling and agility of the integration is improved by facilitating an easy replacement of a service provider by an equivalent provider (same service interface)
What are the 4 ESB deployment patterns?
Global ESB:
- a single ESB (with a single registry) for the entire enterprise, i.e. all the services are available to all participating applications.
Directly Connected ESBs:
- involves several ESBs with a common registry. The pattern is used to standardize the interface of different types of applications within an enterprise, and also to decrease the integration load.
Federated ESB:
- same as the previous, except that one ESB plays the master to control which services are accessible to the participants (i.e. slave ESBs)
Brokered ESB:
- In this pattern, a broker is employed to mediate between connected ESBs. Each ESB controls what type of interactions and which services are allowed outside of the local domain.
What is a adapter?
An adapter is a bridge between systems, applications, or components that cannot communicate directly due to differences in protocols, formats, or technologies. It translates and adapts data for seamless interaction.
What is a wrapper
A wrapper is a type of adapter that creates a new access layer on top of an existing application without modifying its internal implementation.
What types of communication does an adapter have?
Request processing:
- The integration broker sends a request to an
application, by calling its adapter (such as “get stock status”)
Event processing:
- Based on the events triggered by an application, the adapter forwards the event to the integration broker (such as “new customer order request has arrived”). In one solution, events are submitted by the application to the adapter (by calling the adapter), while in the second
solution, the adapter pulls events from an event store in the application.
What is the advantages/disadvantages of SOA?
Advantage:
- The complexity of big monolithic systems, whose parts are closely connected and communicate with one another through
functionality sharing gave rise to SOA.
Disadvantage:
- Flaws in middleware, communication protocol, etc.
- Heavy protocols such as SOAP
