Conference pamsrc::objectbroker_dtc

11.0. "Comparison of DTC with IONA" by SEND::STORM () Tue Jan 07 1997 11:19

This is my comparison of the ObjectBroker Desktop Connection with that
of IONA's bridging product.  It is based on information I have read and
have heard from other sources.  It accurate to the best of my knowledge,
but I have no first hand experience with IONA's bridge.

Please note that this is for DIGITAL INTERNAL USE ONLY, since it includes
customer, partnerships, and 3rd party names.

Summary:

The ObjectBroker Desktop Connection (DTC) is easier to use, more complete, and
more robust than IONA's.  IONA (and other ORB vendors) are focusing on
integrating the Microsoft environment with CORBA in one specific and narrow 
way, that is, programmed clients (like Visual Basic) using OLE Automation to 
interact with CORBA servers.  The DTC is focused on full and transparent
integration of both systems and the full capabilities of both.

Specific comparison points:

- A client using IONA's bridge has to be fully aware that it is talking
  to a Specific IONA server.  DTC is a transparent solution.  The client
  program isn't aware CORBA (much less OBB specific) is involved.

- DTC is 100% compliant with the full bi-directional mapping between COM
  and CORBA as specificed in the OMG COM-CORBA specification.  IONA
  makes that claim, but in reality is only compliant with about 25% of the
  specification. Specifically, they do not support the COM-CORBA mappings
  at all.  They support CORBA to OLE Automation mappings according to the
  OMG spec, but they use a proprientary method for the other direction
  (OLE Automation to CORBA). 

- DTC is integrated with OBB naming (Advertisements) solution. So you can
  use standard ObjectBroker mechanisms for making an object available to
  desktop systes.  No extra mechanisms are involved.  IONA requires a 
  file based set of bridged names, which means that is yet another separate
  item that must be manually managed.  According to Semaphore Nashua, this 
  makes DTC much easier to us.

- IONA generates template for OLE Automation proxy servers. The user has to 
  fill in the code.  DTC generates full working ActiveX controls or proxy 
  objects.  No coding required.  

- DTC generates these full proxy objects with only a couple of mouse clicks
  on the IDL file.

- IONA only supports Automation & Dual interfaces.  That means only scalar
  datatypes.  DTC supports COM and all the datatype mappings specified by
  the OMG.  This is much more natural if you are coding with C++ or J++.  
  Microsoft is also pushing COM now, rather than OLE Automation.


- DTC supports FULL ActiveX Controls and DocObjects.  You'd have to do a
  ton of coding to embed an Iona bridged object into an exchange mail and
  mail it to someone else; or to embed it into a Word document and inplace
  activate it; or to link the ActiveX control into an HTML page and activate
  it from Internet Explorer.  This is ALL done completely by the desktop.

- DTC offers the only secure bridge using DCE security for full Authentication
  between desktop clients and ObjectBroker servers.

- From a strategic point of view, we view COM as an equal player to
  CORBA,  so our bridge emphases transparency between the two models and a
  stronger bidirectional capability.  For example, FORD motor Company is
  very interested in giving CORBA applications native access to the
  COM servers soon to be packaged as part of OFFICE 97.

- Since we are partnering with Visual Edge, there is a much
  higher probability that we will also be able to bridge with other object
  systems in the future (Smalltalk, Oracle, etc).  IONA has decided to do
  the bridge development entirely by themselves.  It's doubtful they will
  be able to keep up with us and our partnership.
  [NOTE: THIS PARTNERSHIP IS COMPANY CONFIDENTIAL AT THIS TIME!]

- DTC automatically provides a GUI for the remote object server, which
  you can use as-is or modify. This visualization gives users access to
  the functions and properties of the remote object without any
  client-side or server-side programming. IONA has nothing like this.