Locating Resources - HP -UX SNAplus2 Administration Manual

SNA Terms and Concepts
Basic APPN Concepts
When setting up a workstation, you must define the CP name. The CP is
also an LU that can support user sessions, and it can be the only LU
defined in your workstation, if you so choose.

Locating Resources

To support communication between TPs, SNAplus2 first establishes a
session between the logical units that control those TPs. APPN enables
the CP on a node to locate LUs throughout the APPN network without
requiring that the node have any configuration information for the
remote LU. The APPN function that dynamically locates LUs in the
network is called directory services. Once a resource has been located, a
route for the session is calculated through the APPN network.
Resource Names
Each node has a unique name consisting of two parts: a network name
and a control point name. Together they constitute a fully qualified CP
name. This name identifies each node to all other nodes in the network.
Similarly, each logical unit is identified by a fully qualified LU name,
consisting of a network name and LU name.
Directory Services
Each APPN node maintains a directory of network resources. Directory
services is the component of the node CP that manages the local
directory database and, in a network node, searches for network
resources throughout an APPN network.
When the node is initialized, it includes the following information:
• Node type (APPN network node, APPN end node, or LEN node)
• Network ID of node
• CP name of node
Each node directory maintains entries for resources (LUs and CPs),
including each resource's fully qualified name, type, and registration
status. The specific resources stored in each local directory depend on the
node type:
• A LEN node maintains a directory that includes its own LUs. It must
also be configured with directory entries for all of its possible partner
LUs. LUs in the APPN network with which the LEN node may want
to establish sessions must be defined to the LEN node as if they
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