With DCE, OSF has established a standard set of services and interfaces that facilitate client-server applications. This is the basis for an open computing environment where networks of multivendor systems appear as a single system to the user. Users can locate and share information safely and easily across the entire network of systems.

Your typical DCE customer is interested in ensuring that they are able to integrate all their systems into an existing DCE environment. Use of an established working environment with well-defined interfaces is key to their work environment. With the DFS product, customers will achieve a consistent unified name space, secure access (Kerberos V), and file protection in a shared file access model.

DCE is called middleware or enabling technology. It is not intended to exist alone, but instead will be used to integrate into a customer's existing distributed environment. DCE is not an application in itself, but is used to build custom applications or to support purchased applications.

DCE/DFS Components

DCE Clients

• DCE Remote Procedure Call (RPC): Allows distributed client-server applications to make procedure calls to different machines in a network in a portable manner.

• Security service: Provides many functions, all directed toward validating that the users, systems, or applications are who they say they are, and determining whether they have permission to access the data or perform the function they are requesting. DCE keeps a database separate from that of the operating system. This database serves the entire heterogeneous cell. (A cell is a group of systems with DCE client software, and at least one system with the CDS server and the security server in common.)

• DCE threads: Provide support for creating and managing multiple sequential flows of execution within a single process in a computer. In a multithreaded application, the multiple flows of execution can carry out concurrent processing of different parts of the application. Threads allow developers to effectively exploit the parallelism inherent in a distributed computing environment for the development of high-performance multithreaded distributed applications.

• Cell directory service (CDS): Allows DCE services and applications to easily locate information about objects, such as files and services, in a distributed environment. The naming model provides global naming, making it easy to locate distributed services and resources on a worldwide basis.

• Global directory agent (GDA): Allows the local CDS to communicate with foreign cells. Using this functionality, users can access servers in a cell other than the one of which their client is a member.

• DCE distributed time service (DTS): Synchronizes time between DCE clients in a cell.

DFS client service

Supports caching of data and uses a token mechanism to synchronize concurrent file access by multiple users. These capabilities enable higher performance and data integrity while accessing files across heterogeneous systems.

DCE development environment

Provides the library calls, and header files to write DCE based applications. The component also includes the the Interface Definition Language (IDL) compiler: IDL is the language used to define remote procedure calls and the DCE Threads Service that provides user-context multiprocessing functionality.

Domestic security option (customers in the United States and Canada only)

This option supports the Data Encryption Standard (DES) as a data encryption mechanism for secure RPCs. A special version of libdce is provided, and it includes functions to implement DES protection.

One of the DES services is packet privacy, a protection level that encrypts data in RPCs sent between DCE applications. United States export restrictions prevent Silicon Graphics from offering packet privacy to customers outside the United States and Canada.

Note: Programs that implement this protection are also subject to these export restrictions.

DCE cell directory server

All cells need at least one CDS. The server provides information to the CDS clients regarding the location of the information they are seeking.

DCE security server

All cells need at least one security server. This server provides secure communications and access by means of authorization and authentication services.

DFS server

DFS extends the local file system model to networked file systems on other computers. This means that DFS files can be distributed across the entire DCE environment. DFS masks the distribution of file systems, making it easy for users and application developers to work with remote files. DFS also masks differences in files stored on different file systems, thus supporting heterogeneous interoperability for information sharing.

Packaging/Licensing

DCE/DFS for IRIX 6.2/6.3/6.4 - Licensing Options

DCE Executive (SC4-DCEXC-1.1C) - this license includes:

DCE clients, DFS client, man pages, OSF documentation, installation and adminstration scripts and binaries.

DCE Development Environment (SC4-DCEDEV-1.1C)

DCE Domestic security option (SC4-DCEDOM-1.1C)

6.2/6.3 only

DCE cell directory server (SC4-DCECDS-S-1.1C/SC4-DCECDS-D-1.1C)

DCE security server (SC4-DCESEC-S-1.1C/SC4-DCESEC-D-1.1C)

DFS server (SC4-DCEDFS-1.1C)

All components except the "DCE Domestic security option" are packaged on the same CD. The DCE servers and DFS server require a FlexLM license.

DCE/DFS for IRIX 6.5.2 and later - Licensing Options

DCE Base Executive/Client 1.2.2a (SC4-DCEXC-1.2.2A)

** This license is now part of the Advanced Workstation Environment (AWE) and Advanced Server Environment (ASE) license. No further licenses/fees are required.

This package includes the DCE clients, DFS client, man pages, OSF documentation, installation and adminstration scripts and binaries, and the development environment.

DCE U.S. Domestic Security 1.2.2a (SC4-DCEDOM-1.2.2A) This package is still a separate license and fee.

Silicon Graphics supports the following components of DCE/DFS:

1 = OSF Version 1.1
2 = OSF Version 1.2.2

* 6.5.2 and later.