SNA Terms and Concepts

 

Basic SNA Concepts

 

As shown in Figure 1-3, “Communication between Transaction Programs

 

and Logical Units,” information is exchanged between TPs and LUs to

 

enable one node to communicate with another. Although the TPs appear

 

to be communicating directly, the LUs on each node are the

 

intermediaries in every exchange.

Figure 1-3

Communication between Transaction Programs and Logical

 

Units

SNA defines two types of conversations: basic and mapped. These two types of conversations use different methods to indicate the length of transmitted or received data packages to be passed between SNAplus2 and the TP.

•In a basic conversation, data must be formatted by the TP as logical records before being presented to the SEND function.

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Chapter 1