Specifications

Distributed Computing Support
3.2 OpenVMS Networking Support for Distributed Computing
DECnet/OSI for OpenVMS is compatible with DECnet for OpenVMS, a Phase IV
product. Nodes running DECnet/OSI for OpenVMS and nodes running DECnet
for OpenVMS can communicate on the same network.
Other DECnet products provide services for distributed processing over the
network. These products include DECdts, a distributed time service; DECdns, a
distributed name service; and DECdfs, a distributed file service.
DEC TCP/IP Services for OpenVMS enable TCP/IP connections and supply
Network File System (NFS) server capabilities. TCP/IP is the protocol used by
UNIX systems on the Internet. NFS permits UNIX clients to access OpenVMS
files and UNIX files stored on the OpenVMS system.
DEC TCP/IP Services for OpenVMS permit an OpenVMS system to become a full
participant in TCP/IP networks. The product includes the following:
• Set of industry-standard communication protocols (TCP, IP, FTP, Telnet, and
other protocols)
• Digital Remote Procedure Call (DECrpc) for OpenVMS
• NFS server software
3.3 OpenVMS Client/Server Capabilities
One style of distributed computing that permits resource sharing between
different systems is client/server computing. In the client/server environment,
portions of an application are distributed across the network between servers
and clients. The server is any system that provides a service or resource
to other systems. The client is a system requesting a service. This style of
computing allows each portion of a distributed application to run in its own
optimal environment.
VMScluster software and Network Application Software (NAS) support
client/server computing. VMScluster software enables client/server computing
among OpenVMS VAX and OpenVMS AXP systems. NAS software supports
client/server computing among OpenVMS VAX, OpenVMS AXP, and DEC
OSF/1 AXP systems, and among Digital systems and other vendors’ systems
including UNIX, MS–DOS, Microsoft Windows, and Windows NT systems.
PATHWORKS software, which is part of NAS, enables complex information-
sharing environments involving PC clients and operating system servers. For
more information about PATHWORKS products, see Section 3.3.4.
3.3.1 OpenVMS Client/Server Configurations
OpenVMS systems support a wide variety of client/server configurations.
A single OpenVMS system or a VMScluster can function as a server. OpenVMS
servers can provide file access, printing, application services, communication
services, and computing power as application engines to clients on desktop
devices or in laboratories or factories.
Clients requiring resources can be any of the following:
• Personal computers
• Workstations
• Point-of-sale devices
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