SNAX Connection Manager (SNAX/CM) Manual

1 Introduction to SNAX
Connection Manager (SNAX/CM)
097842 Tandem Computers Incorporated 1–1
This section describes SNAX Connection Manager (SNAX/CM), the features
supported, and the components that work together to implement connection
management applications.
What Is SNAX
Connection Manager?
SNAX Connection Manager (SNAX/CM) is a subsystem that allows you to manage
connections for calls coming in to and going out from a Tandem system over an X.25
or Token-Ring network.
SNAX/CM works in conjunction with SNAX Extended Facility (SNAX/XF), a Tandem
communications access method that implements part of the IBM Systems Network
Architecture (SNA). SNAX/XF allows applications on a Tandem system to
communicate with SNA devices attached to Tandem systems and with programs
residing on an SNA host system.
SNAX/CM is an executable program that runs as a nonprivileged application process.
Integral to SNAX/CM is SXCMGR, a set of procedures that provide the protocol at the
boundary of SNAX/CM to interface with SNAX/XF. Applications can use SNAX/CM
to manage the physical connections of lines, allowing users to:
Call out to remote devices or other host systems
Start an application on connected LUs without device input
Receive incoming calls from remote devices or other host systems, and disable
incoming calls
Check the connection status of a call
Verify calling addresses for incoming calls, as well as verify the node identification
(PUID) of calling PUs
Monitor and maintain a log file for call connections and disconnections
Issue messages to user-created server processes about connections, disconnections,
call validation, and commands issued.
Note Although switched virtual circuits (SVCs) and permanent virtual circuits (PVCs) can exist on the same
X.25 line, SNAX/CM provides no service for PVCs.
SNAX/CM features both a command interpreter and a programmatic interface so
users can issue commands either from a terminal or from an application. (SNAX/CM
commands are described in Section 3.)
Components of a
SNAX/CM Environment
Figure 1-1 shows the components used in a SNAX Connection Manager process,
whether users run it interactively or programmatically. These components include a
log file, use of alias LU names (described later in this section), a user-written server
process, the SNAX/XF service-manager process (with a default name of $SSCP), and
communication lines.