Defining Connectivity Components

Defining Link Stations

Defining Link Stations

To communicate with other nodes in an SNA network, you must configure the characteristics of a link station (LS) to an adjacent node in the SNA network. Before you can define a link station, you must define a port for the adapter (and link protocol) you are using. Most of the information needed to configure a link station is the same, whatever protocol is being used.

A link station represents the logical path through the SNA network between the SNAplus2 local node and a remote computer. The remote computer can be any of the following:

• A host computer, on which SNAplus2 accesses a host program using 3270, RJE, or LUA communications (or uses APPC or CPI-C for program-to-program communications)

• A peer computer, with SNAplus2 and the remote computer communicating as equal partners (the typical arrangement in an APPN network)

• A downstream computer that uses the SNAplus2 PU concentration

 

feature or DLUR feature in order to access a host

 

A link station is associated with a specific port; you can define one or

 

more link stations on each port.

 

Each link station that supports dependent traffic has an associated PU

 

(physical unit). Because PUs are associated with link stations, SNAplus2

 

does not treat them as separate resources; they are configured as part of

 

link station configuration, and are started and stopped as part of

 

starting and stopping link stations. Link stations are shown in the

 

connectivity section of the Node window; PUs are not shown in any

 

window.

 

In most circumstances, you need to add a link station to the port.

NOTE

 

However, if you want to use a dynamically created link station for APPC

 

traffic only, for situations in which the link is always activated from the

 

remote node, you do not need to explicitly configure one.

 

If a remote node attempts to connect to the local node, but no link station

 

is defined that matches the address specified on the incoming call,

 

SNAplus2 can define one implicitly if a suitable port has been defined on

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Chapter 5