HP UX SNAplus2 manual Transaction Programs, Application Programming Interfaces

SNA Terms and Concepts

Basic SNA Concepts

Each node connected to a network has one or more link stations, which are the hardware and software in a node that control data flow to a specific adjacent node. To establish communication between two adjacent nodes, one of the link stations must first activate the link between the nodes.

Transaction Programs

Programs that exchange information across the SNA network are called transaction programs (TPs).

Following are examples of application programs that can include SNA

TPs:

•Emulation programs

•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 “Logical 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 “Application Programming Interfaces”).

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

Chapter 1 31