| Technical Areas
WWW and OOP
"What is the W3C position on active document technologies
like ActiveX, IIOP, and Java?" W3C is vendor-neutral, and has no
position on any vendor or product. But we are very interested in active document
technology. See: W3C Activity: Object Technology and
the Web.
Background
The power of the Web as a new medium derives not only from its ability
to allow people to communicate across vast distances and different times,
but also from the ability of machines to help people communicate and manage
information. The Web is a complex distributed system, and Object Technology
has been an important part of managing the complexity of the Web from
its creation.
Object Technology continues to influence and impact the web in a number of
areas:
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Scripting
-
Client side scripting has been an interesting area of research and
experimentation since the
early days of the
web, but now it being deployed, and information providers need interoperable
support.
-
Embedded Multimedia Components
-
The web is a natural medium for component software technology such as Plug-Ins,
Java applets, ActiveX controls, OpenDoc parts.
-
Web Server Components
-
CGI, along with HTML and forms, is an important part of the platform
of technologies used to deploy application services on the web. But its design
presents a performance limitation in many situations. A
number of mechanisms for interfacing applications
to web servers, from C-callable APIs to network protocols to distributed
objects gateways have sprung up to fill the need.
-
Agents and Mobile Code
-
Mobile code can be used to automate information access: searching, brokering,
and even manipulating data with mobile agents is an interesting trend.
This is an investigation of the integration of distributed object technologies
with the web, and the duality between application programmers' interfaces
(APIs) and network protocols.
History
Contents
-
Schools of Thought
-
Architectural viewpoints: CORBA/OMG, DCE, ...
-
Issues in the Development of Distributed Hypermedia
Applications
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Concurrency, Safety, Naming, Type Systems...
-
Technologies for Development of Distributed
Applications
-
Modula-3, ILU, python, ...
-
Hypermedia APIs/Protocols
-
The various players in the distributed objects are separated into camps based
on architectural interoperability, and listed in chronological order (roughly).
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DCE
-
OSF is the controlling body. The distributed
object model inherits from something called TI-RPC, which is C++ish. The
RPC system came from Apollo, I think.
-
CORBA
-
Common Object Request Broker Architecture.
OMG, The Object Management Group,
is the controlling organization. The Java/Sun camp is CORBA-happy. So is
OpenDoc (by CILabs).
-
COM
-
Microsoft's Component Object Model -- the underpinnings of ActiveX, DCOM,
and OLE.
-
Plan 9
-
This is the basis of Inferno. The Bell
labs guys started over with the "everything is a file" concept. 9P is a really
nifty protocol. Supports union links.
-
ILU
-
Inter-Language Unification. A project from Xerox PARC. The architecture has
a single interface specification language, plus an extensible set of message
formats (called protocols, of all things, in ILU-terminology), and transports.
For example, an XDR/UDP combo allows interoperability with SunRPC clients
and servers. The CORBA IIOP is supported in version2.0. Xerox courier is
supported via another combination. Calls within the same address space are
also supported. All these combinations can be mixed in the same process,
so that gateways are trivial.
Language support includes C, C++, Modula-3, python, Common Lisp and tcl.
Java is in the works.
See: Why ILU?
Misc Resources
This is some stuff that seemed relevant for one reason or another, but I
haven't had time to annotate it and integrate it with the rest of this
information.
Connolly
$Date: 1997/01/08 22:42:19 $