HP-UX SNAplus2 R7 General Information

Introducing SNAplus2
SNAplus2 Resources
Unrestricted LUs support LUA, and upstream LUs that provide host communication with downstream
LUs through PU concentration.
LUs can also be grouped into LU pools. A user session can be assigned to a pool of LUs, rather than to a
specific LU, so that it can use any available LU within that pool.
Modes and class of service (COS) definitions
A mode specifies a set of characteristics that a local LU (type 6.2) uses to communicate with its partner
LU. These characteristics include information on the way data is transmitted between the two LUs (such as
maximum RU lengths and pacing window sizes), and on whether the LUs can establish parallel sessions.
In addition, you might need to specify requirements for the communications path between the LUs, such as
enforcing a certain level of network security, minimizing transmission time, or avoiding the use of expensive
communications links. These requirements can be defined using a class of service (COS), which specifies
minimum and maximum acceptable values for characteristics such as transmission time, transmission cost,
and network security, and weightings associated with different ranges of these values. The COS definition
enables the node to calculate the best route across the network when two or more routes to the same remote
LU are available.
If the SNAplus2 node is a network node, the definition of each mode includes the name of the required COS
for that mode. If the SNAplus2 node is a LEN node or end node, you do not need to associate a COS with
the mode; the COS name is determined dynamically.
SNA defines a number of standard modes and associated COSs that cover the requirements of most systems;
in general, you do not need to define additional modes and COSs.
2.2.2 SNAplus2 Applications
SNAplus2 includes end user applications, as well as application programming interfaces that you can use to write
your own applications. SNAplus2 supports the following end user applications:
• 3270 emulation program
• RJE workstation daemon
• APPC transaction programs
• CPI-C applications
• APPC Application Suite
• LUA applications
• UNIX command facility
• Service point command facility
These are all user-space programs. SNAplus2 supports multiple copies of the 3270 emulation program and multiple
APPC TPs, CPI-C applications, and LUA applications, running concurrently.
User Applications
SNAplus2 provides the following user applications:
3270 Emulation Program
SNAplus2 provides 3270 emulation software that lets users log on to and use IBM host systems from HP-UX
computers. Using this software, a user can transfer files between the local and host computers, and control
display and printer emulation sessions. A user can also customize some of the 3270 emulation features, such
as key mapping and display attributes, and store them in the style file that is used to initialize an emulation
session. SNAplus2 3270 emulation also enables users to run HLLAPI applications.
The 3270 emulation program uses the node’s type 0–3 LU resources. In addition, SNAplus2 requires
definitions for the 3270 users on the system, identified by their login IDs, and the 3270 sessions available to
them. User and session definitions for 3270 emulation are configured in the domain configuration file.
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