CSSE4004 - Lecture 8

Binds to a variety of services including RMI, JDBC, JNDI, JMS

Supports stateless objects

Supports stateful session

Uses JSON (Java serializable object networking) to represent the data

Supports both persistent and transient communication

Uses an IDL based on C data types

Uses network pointer for addressing objects which encapsulates an object’s identity and location information

Is object based

None of the other options are false

Starts servers if necessary

Converts messages to formats compatible with the server

Adding a transparency layer between a server and the implementation repository

Filtering messages which are incompatible with a server

Location of servants

Separating interface and implementation

Activation/deactivation of the servant’s container (the server process) where necessary

Scheduling the servant’s container (the server process) to be restarted when a message lease expires

Static invocation requires that interfaces are known when the application is developed

Interfaces are usually specified in an interface definition language (IDL)

Dynamic invocation allows to compose RMI at run time

Dynamic invocation is only possible over IP based protocols

allows clients to invoke objects without a precompiled stub

only compatible with dynamic/interpreted languages such as Python

Faster because pre-compiled stubs do not need to be loaded from memory

requires that the client knows the parameter list and function name in advance

Most useful for cross platform and application interoperability eg. business to business integration

XML encoding has a high parsing overhead

SOAP may be used in place of GET / POST

HTTP is stateful

The state of the object is not distributed

The state of the object is distributed

The state of the object is replicated on both the client and the server

The application must decode results returned by the function from the encoding they were transmitted in

Interface definition, similar to IDL

Discovering/locating services dynamically

Avoiding the drawbacks of XML by enabling the use of binary encoding

Enabling interoperability with .NET and other languages such as Java

exists as long as the server hosting the object

exists even if it is currently not contained in the address space of any server

a record stored in a database would be a transient object

most distributed computing platforms only support persistent objects

Is a difference between Remote Method Invocation and RPC

Object references can be passed between remote processes

Process holding an object reference has to bind to the object before invoking any method

Binding results in a reverse pointer being placed in process’s address space

Supports UDP or TCP/IP

Supports SOAP and binary encoding

Similar to CORBA RMI

RMI call includes the object URI in the request

.NET Remoting

.NET Web Services

WCF (Windows Communication Foundation)

WCI (Windows Communication Interface)