SNA Terms and Concepts

Basic SNA Concepts

dependent LU requester (DLUR) function enables session traffic from dependent LUs to flow over APPN networks. For more information about DLUR, see “Accessing Subarea Networks from APPN Networks”.

A dependent LU on a peripheral node is always the secondary LU.

An independent LU can establish sessions with other independent LUs without the aid of an SNA host. LU 6.2 is the only LU type that can be independent.

An independent LU can act as a primary or as a secondary LU when establishing a session.

Multiple and Parallel Sessions

An independent LU can participate in sessions with more than one remote LU at the same time (multiple sessions).

An independent LU can also participate in parallel sessions, or multiple concurrent sessions with the same remote LU.

Dependent LUs (including dependent LU 6.2) cannot have multiple sessions.

LUs with multiple and parallel sessions are shown in Figure 1-2, “Multiple and Parallel Sessions.” LUA and LUB have parallel sessions. LUA also has multiple sessions: two with LUB and one with LUD. LUD has multiple sessions with LUA and LUC.

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Chapter 1