HP-UX SNAplus2 R7 Administration Guide

SNA Terms and Concepts

Basic SNA Concepts

• File transfer

• Database transaction processing

• Network management

• Centralized data services

The TP accesses the network through a logical unit (LU) that establishes and maintains a session with a partner LU

on another node. For more information about logical units, see Section 1.2.6,

Network Accessible Units.

Note

SNAplus2 includes sample TPs for most supported APIs. For more information on sample

TPs, refer to the programmer’s guide for the API. You can also purchase SNA TPs as part

of other products or create your own TPs (see Section 1.2.5, Application Programming

Interfaces).

1.2.5 Application Programming Interfaces

SNA TPs are written using application programming interfaces (APIs). APIs provide speciﬁc subroutines that enable

SNA TPs to access SNA functions, such as those for exchanging data and performing control functions. These

subroutines enable an SNA TP to communicate with another SNA TP on a remote node.

SNAplus2 includes the following APIs on all platforms:

• APPC—LU type 6.2 only

• CPI-C (Common Programming Interface for Communications)—LU type 6.2 only

• CSV (Common Service Verb) API

• HLLAPI (high-level language application programming interface)—as part of the SNAplus2 3270 emulation

program

• LUA API

In addition, SNAplus2 includes the following proprietary programming interfaces:

• MS (Management Services) API (only for HP-UX systems)

• NOF (Node Operator Facility) API

For an overview of the APIs provided with SNAplus2, see Section 2.3.3, Application Programming Interfaces.

1.2.6 Network Accessible Units

Communication between a TP and the SNA network occurs through network accessible units or NAUs (formerly

called “network addressable units”), which are unique network resources that can be accessed (through unique local

addresses) by other network resources.

SNA provides the following types of NAUs:

• Physical units (see Section 1.2.6, Network Accessible Units)

• Logical units (see Section 1.2.6, Network Accessible Units)

• Control points (see Section 1.2.6, Network Accessible Units)

Note

Because TPs are considered users of the network, not components, they are not classiﬁed

as NAUs.