OSI/MHS Configuration and Management Manual

OSI/MHS Configuration and Management Manual—424827-003
Glossary-27
RS (remote operations service) process. The process in the RS group that implements the
ROSE protocol. The RS interfaces to the OSI/AS services, manages associations
from RUAs, encodes and decodes messages, and creates and deletes PDUs in the
MR or MS PDU stores as submit and retrieval operations are successfully completed.
RS (remote operations service) group. The OSI/MHS group that implements the remote
operations service, giving remote user agents access to an X.400 network through a
message store. An RS group consists of a single RS process and a PDU store. There
can be zero, one, or more RS groups in a single OSI/MHS subsystem.
RTSE (reliable transfer service element). An Application Layer service definition and
protocol supporting the reliable exchange of application data, defining such services as
recovery from end-to-end failures and reporting delivery status to the sender. In
OSI/MHS, the RTS process implements the RTSE.
RTS (reliable transfer service) process. A process in the MR group that implements the
RTSE protocol and accesses the PDU store to read and write messages.
RUA (remote user agent). A user agent that submits and retrieves messages through a
message store and resides on a system or device other than the system that provides
the message store. See also LUA.
SAP (service access point). In OSI, a logical location between two layers, through which the
services of the lower layer are made available to local users, and those of the upper
layer are made available to remote systems. (The SAP is always named after the
lower layer; for instance, an SSAP is between the Session and Presentation Layers.)
For the Network Layer and below, local users and remote systems use the Network
Service Access Point (NSAP) address to establish and maintain connections. For the
Transport Layer and above, local users and remote systems do not use SAP
addresses explicitly; rather, they specify an address called the “(N)-address,”
consisting of one or more selectors. See also selector.
S-selector. See SSEL.
SC (store cleaner) process. A process that scans the MR group PDU store periodically and
removes messages that have been fully processed.
SCF (Subsystem Control Facility). A part of DSM, used to provide a common, interactive
management interface for configuring, controlling, and collecting information from data
communications products.
SCP (Subsystem Control Point). In DSM, the management process for all NonStop data
communications subsystems. There can be several instances of this process.
Applications using SPI send all commands for data communications subsystems to an
instance of this process, which in turn sends the commands on to the manager
processes of the target subsystems. SCP also processes a few commands itself. It