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ONC+ Developer's Guide

Chapter 1 Introduction to ONC+ Technologies

This chapter briefly introduces ONC+ technologies, the SunTM open systems distributed computing environment. The ONC+ technologies are the core services available to developers who implement distributed applications in a heterogeneous distributed computing environment. ONC+ technologies also include tools to administer client/server networks.

Figure 1–1 shows an integrated view of how client-server applications are built on top of ONC+ technologies, and how they sit on top of the low-level networking protocols.

Figure 1–1 ONC+ Distributed Computing Platform

Applications, NFS, and NIS+ are above TI-RPC and XDR, which are above TLI and Sockets, which are above low-level network protocols.

Brief Description of ONC+ Technologies

ONC+ technologies consist of a family of technologies, services, and tools. These technologies are backward compatible and interoperate with the installed base of ONC services. The main components are described. This guide covers the technologies that require the use of programming facilities.

TI-RPC

The transport-independent remote procedure call (TI-RPC) was developed as part of UNIX System V Release 4 (SVR4). TI-RPC makes RPC applications transport-independent by enabling a single binary version of a distributed program to run on multiple transports. Previously, with transport-specific RPC, the transport was bound at compile time so that applications could not use other transports unless the program was rebuilt. With TI-RPC, applications can use new transports if the system administrator updates the network configuration file and restarts the program. Thus, no changes are required to the binary application.

XDR

External data representation (XDR) is an architecture-independent specification for representing data. It resolves the differences in data byte ordering, data type size, representation, and alignment between different architectures. Applications that use XDR can exchange data across heterogeneous hardware systems.

NFS

NFS is a distributed computing file system that provides transparent access to remote file systems on heterogeneous networks. In this way, users can share files among PCs, workstations, mainframes, and supercomputers. As long as users are connected to the same network, the files appear as though they are on the user's desktop. The NFS environment features Kerberos V5 authentication, multithreading, the network lock manager, and the automounter.

NFS does not have programming facilities, so it is not covered in this guide. However, the specification for NFS is available through anonymous ftp at:

NIS+

NIS+ is the enterprise naming service in the Solaris environment. It provides a scalable and secure information base for host names, network addresses, and user names. NIS+ makes administration of large, multivendor client/server networks easier by being the central point for adding, removing, and relocating network resources. Changes made to the NIS+ information base are automatically and immediately propagated to replica servers across the network. This propagation ensures that system uptime and performance are preserved. Security is integral to NIS+. Unauthorized users and programs are prevented from reading, changing, or destroying naming service information.