Open System Services Management and Operations Guide (G06.25+, H06.03+)

Introducing Open System Services
Open System Services Management and Operations Guide—527191-002
1-16
Interprocess Communication Facilities
HP provides the OSS sockets local server, $ZPLS, as a transport-provider process for
OSS AF_UNIX sockets. You manage the OSS sockets local server through the SCF
module of the OSS Monitor, as described in Section 4, Managing Servers.
HP provides processes for each of its TCP/IP implementations as transport-provider
processes for OSS and Guardian AF_INET and AF_INET6 sockets. You manage an
AF_INET or AF_INET6 transport-provider process through the SCF commands for the
TCP/IP subsystem that you use for specific sockets.
AF_INET or AF_INET6 Sockets
Internet domain sockets allow application programs to communicate with each other or
with terminals using the underlying TCP/IP processes that also provide Telserv
terminal access for your system. AF_INET sockets provide access through Internet
Protocol (IP) version 4 addresses; AF_INET6 sockets provide access through IP
version 6 addresses.
For Internet domain sockets using NonStop TCP/IP, the socket application
communicates with the $ZTAnn process. The $ZTAnn process in turn provides Internet
access through the transport-provider process of TCP/IP.
The AF_INET or AF_INET6 transport-provider process is named $ZTCn, $ZSAMn, or
another name chosen by your site. The OSS sockets software assumes that the
default name is $ZTC0 when no other process name is specified by an appropriate
method. This guide uses $ZTC0 for discussions that involve the Internet domain
transport-provider process.
See the:
•
TCP/IP Configuration and Management Manual
•
TCP/IP (Parallel Library) Configuration and Management Manual
•
TCP/IPv6 Configuration and Management Manual
for information on the configuration and management of the corresponding transport-
provider process.
Figure 1-6 on page 1-18 shows the processes related to providing OSS AF_INET
sockets for NonStop TCP/IP. The diagram shows two systems, referred to as Node A
and Node B, each with two processors. In Node A, only one of the processors has a
transport-provider process ($ZTC0), whereas in Node B, each processor has its own
transport-provider process ($ZTC0 and $ZTC1). Each processor has its own transport-
agent process ($ZTAnn).
The application processes (Processes 1 through 4) communicate with each other
through the transport-provider ($ZTCn) processes, with data being carried back and
Note. A copy of the transport-provider process is not necessarily given the default name of
$ZTC0. However, as long as either the DEFINE =TCPIP^PROCESS^NAME matches the
running transport-provider process or the OSS application selects the transport-provider
process name by calling socket_transport_name_set(), OSS sockets function properly.