SNA Terms and Concepts

Basic APPN Concepts

Figure 1-5

LEN Node Directory

 

To establish a session with an LU on a node that is not directly attached,

 

Node LEN1 sends an LU-LU session activation (BIND) request to its

 

network node server (Node NNA). The server automatically locates the

 

destination LU and forwards the BIND.

 

In this example, Node LEN1 can establish a session with LU1 on Node

NOTE

 

EN1 through its network node server, NNA. However, LU2 on Node EN1

 

is not defined in the directory for Node LEN1, so Node LEN1 cannot

 

establish sessions with that LU.

 

End Node Directories. When an LU is not represented in an end

 

 

node directory, the end node initiates a LOCATE search to find the desired

 

LU. To activate the search for a remote LU, the end node invokes the

 

services of its network node server. An example of an end node directory

 

is shown in Figure 1-6, “End Node Directory.”

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Chapter 1