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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN"><HTML><HEAD><SCRIPT LANGUAGE="JavaScript"><!--function popUp(pPage) { var fullURL = document.location; var textURL = fullURL.toString(); var URLlen = textURL.length; var lenMinusPage = textURL.lastIndexOf("/"); lenMinusPage += 1; var fullPath = textURL.substring(0,lenMinusPage); popUpWin = window.open('','popWin','resizable=yes,scrollbars=no,width=525,height=394'); figDoc= popUpWin.document; zhtm= '<HTML><HEAD><TITLE>' + pPage + '</TITLE>'; zhtm += '</HEAD>'; zhtm += '<BODY bgcolor="#FFFFFF">'; zhtm += '<IMG SRC="' + fullPath + pPage + '">'; zhtm += '<P><B>' + pPage + '</B>'; zhtm += '</BODY></HTML>'; window.popUpWin.document.write(zhtm); window.popUpWin.document.close(); // Johnny Jackson 4/28/98 }//--> </SCRIPT> <META NAME="Author" Content="Bryan Flores"> <META HTTP-EQUIV="Content-Type" CONTENT="text/html;CHARSET=iso-8859-1"> <TITLE>Teach Yourself CORBA In 14 Days -- Appendix C -- What Lies Ahead? The Future of CORBA</TITLE></HEAD><BODY TEXT="#000000" BGCOLOR="#FFFFFF"><CENTER><H1><IMG SRC="../button/sams.gif" WIDTH="171" HEIGHT="66" ALIGN="BOTTOM" BORDER="0"><BR><FONT COLOR="#000077">Teach Yourself CORBA In 14 Days</FONT></H1></CENTER><CENTER><P><A HREF="../apb/apb.htm"><IMG SRC="../button/previous.gif" WIDTH="128" HEIGHT="28"ALIGN="BOTTOM" ALT="Previous chapter" BORDER="0"></A><A HREF="../index.htm"><IMGSRC="../button/contents.gif" WIDTH="128" HEIGHT="28" ALIGN="BOTTOM" ALT="Contents"BORDER="0"></A> <HR></CENTER><CENTER><H1><FONT COLOR="#000077">Appendix C <BR>What Lies Ahead? The Future of CORBA</FONT></H1></CENTER><UL> <LI><A HREF="#Heading1">Looking Briefly Through the Rearview Mirror</A> <LI><A HREF="#Heading2">In the Near Future: CORBA 2.1</A> <LI><A HREF="#Heading3">On the Horizon: CORBA 3.0</A> <UL> <LI><A HREF="#Heading4">OMG Task Forces</A> <LI><A HREF="#Heading5">Task Forces of the Platform Technology Committee</A> <LI><A HREF="#Heading6">Task Forces of the Domain Technology Committee</A> <LI><A HREF="#Heading7">What It All Means</A> </UL> <LI><A HREF="#Heading8">Looking Beyond</A> <UL> <LI><A HREF="#Heading9">CORBA Development in the Future</A> <LI><A HREF="#Heading10">Challenges Facing CORBA</A> </UL> <LI><A HREF="#Heading11">Summary</A></UL><P><HR SIZE="4"><CENTER><H1></H1></CENTER><P>This book has focused largely on what you can do with CORBA today<I>.</I> Butwhat about six months from now, or a year from now, or even further in the future?To plan for the systems you will build tomorrow, you want to know where CORBA isgoing to be at that time. This chapter looks at some proposed additions to CORBAand examines the overall direction CORBA is taking.<H2><A NAME="Heading1"></A><FONT COLOR="#000077">Looking Briefly Through the RearviewMirror</FONT></H2><P>To predict where CORBA is heading, it is helpful to know some of its history.Recall from Day 1, "Getting Familiar with CORBA," that CORBA first materializedaround 1990, shortly after the Object Management Group--CORBA's controlling organization--wasfounded. CORBA 1.0, followed shortly by CORBA 1.1, laid the groundwork for distri-butedobject communication. In 1994, the OMG adopted the 2.0 version of the CORBA specification,the primary goal of which was to define a standard for interoperability for ORBsproduced by different vendors. (Recall that an ORB, or Object Request Broker, isthe component of CORBA that facilitates communication between objects.) CORBA 2.0was a major step towards achieving interoperability between various products, butit still lacked some capabilities. Most notable was its inability to pass objectsby value (as discussed on Day 10, "Learning About CORBA Design Issues").Simultaneously, the OMG developed specifications for additional functionality inthe form of CORBAservices and CORBAfacilities.<H2><A NAME="Heading2"></A><FONT COLOR="#000077">In the Near Future: CORBA 2.1</FONT></H2><P>CORBA 2.1, adopted in September 1997, made some incremental changes to the CORBAspecification:<UL> <LI>Revisions to the interoperability specification<BR> <BR> <LI>Extensions to the IDL language, notably the <TT>long long</TT> (64-bit) integer types and <TT>wchar</TT> (wide character) type<BR> <BR> <LI>The inclusion of two standard language mappings: COBOL and Ada</UL><P>None of these changes is earth-shattering, but the IDL extensions in particularbring CORBA up-to-date with respect to languages and operating systems that support64-bit integer types and multi-byte character sets.<H2><A NAME="Heading3"></A><FONT COLOR="#000077">On the Horizon: CORBA 3.0</FONT></H2><P>Coming up on the horizon is the CORBA 3.0 standard, the next major step in theevolution of CORBA. At the time of this writing, the OMG has not yet announced whatcapabilities and enhancements will be included in CORBA 3.0, but by taking a lookat the current Requests For Proposals (RFPs) and Requests for Information (RFIs),you can make some reasonable guesses about what to expect in the next major iterationof the CORBA specification.<H3><A NAME="Heading4"></A><FONT COLOR="#000077">OMG Task Forces</FONT></H3><P>A knowledge of how the OMG operates is also helpful in predicting what CORBA 3.0might include. The OMG includes two Technology Committees (TCs) that charter variousTask Forces to solve particular problems. To this end, the Task Forces issue RFPsand RFIs to find potential solutions from the industry at large.</P><P>Currently, the Domain Technology Committee and the Platform Technology Committeehave chartered a number of Task Forces that have current outstanding RFPs and RFIs.This section provides a brief overview of these Requests, which will probably drivemuch of the content of CORBA 3.0 when it is adopted.<H3><A NAME="Heading5"></A><FONT COLOR="#000077">Task Forces of the Platform TechnologyCommittee</FONT></H3><P>The work performed by the Platform Technology Committee Task Forces is includedin the CORBA specification itself at some point. For example, there are Task Forcesto resolve issues of COM/CORBA interworking (recall that COM is Microsoft's ComponentObject Model), to create IDL mappings for various programming languages, and to proposeadditional features to CORBA. Currently, the Task Forces of the Platform TechnologyCommittee include the Object Analysis and Design Task Force (OA&D TF) and theORB/Object Services Task Force.</P><P>Most of the descriptions here are quoted directly from the OMG Web site. Detailson the various Task Forces are available at <A HREF="http://www.omg.org/omg00/task.htm"><TT>http://www.omg.org/omg00/task.htm</TT></A>;details on the work in progress of the Technology Committees (as well as descriptionsof the RFPs and RFIs themselves) are available at <A HREF="http://www.omg.org/library/schedule.htm"><TT>http://www.omg.org/library/schedule.htm</TT></A>.<H4><FONT COLOR="#000077">ORB and Object Services Platform Task Force</FONT></H4><P>According to the charter of the ORB and Object Services Platform Task Force, itsmission is to solicit, evaluate, and select specifications for recommendations tothe Platform Technology Committee for adoption by OMG in the areas of ORB technology(which falls under the CORBA specification) or general purpose Object Services (whichfall under CORBAservices). Furthermore, the charter states that such specificationsshould be fundamental for developing useful CORBA-based applications composed ofdistributed objects, should provide a universal basis for application interoperability,or support higher level facilities and frameworks.</P><P>The current RFIs and RFPs issued by the ORB and Object Services Platform TaskForce include the following:<UL> <LI><I>ORB and Object Services RFI 1 </I>(Internet). An RFI on Internet-related services and interfaces, to help with the integration and inclusion of OMG and CORBA objects on the Internet. The overall goal of this RFI is to collect information from various communities to help guide the OMG's IPSIG and the OMG in the adoption of specifications that will scale the OMG Object Management Architecture to the Internet and further populate or align with Internet standards, protocols, tools, and utilities. This RFI solicits relevant information in several areas: requirements, architectures, designs, projects, products, protocols, and standards.<BR> <BR> <LI><I>ORB and Object Services RFI 2 </I>(Realtime). This Request For Information solicits input regarding the need for and availability of technology for the following: realtime operating environment suitable for supporting realtime Object Request Brokers; realtime Object Request Brokers; object services, common facilities, and extensions for realtime; and general realtime features that would apply to the above in an object technology context.<BR> <BR> <LI><I>Multiple Interfaces and Composition RFP</I>.<B><I> </I></B>Multiple Interfaces RFP deals with the resolution of conflict between multiple IDL interfaces on the same object. The composition facility provides the means for objects to be composed of logically distinct services by the use of multiple interface definitions. The composition facility has been proposed as a base of many system requirements.<BR> <BR> <LI><I>Messaging Service RFP (ORBOS RFP1)</I>.<B> </B>An RFP soliciting proposals of services and ORB enhancements designed to manage asynchronous messages in distributed object systems, including ordering and quality of service of requests.<BR> <BR> <LI><I>Objects-by-Value RFP (ORBOS RFP2)</I>.<B> </B>This RFP seeks proposals for interfaces that provide for the passing of CORBA objects by value (rather than by reference) as parameters in CORBA object operations. Passing objects by value is more efficient and straightforward in many circumstances.<BR> <BR> <LI><I>Java to IDL RFP (ORBOS RFP5)</I>.<B> </B>This RFP solicits proposals that will enhance the CORBA Java language mapping with a Java-to-IDL mapping. A Java-to-IDL⌨️ 快捷键说明
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