B2B Integration : A Practical Guide to Collaborative E-commerce

Middleware Technologies 239
that lets them use the OMG's HOP protocol for remote invocations and
allows Java servers to be invoked by CORBA clients written in any
CORBA-supported programming language.
Firewall Specification
The CORBA 3 firewall specification will define the capabilities CORBA
needs to safely traverse firewalls.
Interoperable Naming Service
The interoperable name service defines one URL-format object reference,
corbaloc, that can be typed into a program to reach defined services at
a remote location, including the naming service. A second URL format,
corbaname, actually invokes the remote naming service using the name
that the user appends to the URL and retrieves the IOR of the named
object.
Quality of service control
The new messaging specification defines a number of asynchronous and
time-independent invocation modes for CORBA and allows both static
and dynamic invocations to use every mode.
CORBA components package
The three major parts of CORBA components are:
• A container environment that packages transactionality, security and
persistence and provides interface and event resolution;
• Integration with EJBs; and
• A software distribution format that enables a CORBA component
software marketplace.
8.4.4. Windows DNA — COM+
Windows DNA has evolved from the middleware services originally
provided in Windows NT, including the Component Object Model
(COM), Distributed COM (DCOM), Microsoft Transaction Server (MTS)
and Microsoft Message Queue (MSMQ). The foundation of Windows