HP-UX SNAplus2 General Information (October 1998)

Chapter 2 35
Introducing SNAplus2
SNAplus2 Resources
PU Concentration
Normally, a dependent LU session requires a direct communications link
to the host computer. However, a node running SNAplus2 that has a
direct communications link to the host can also provide PU concentration
facilities to LUs on downstream computers, enabling them to access the
host over the communications link from the SNAplus2 node.
The downstream computer must contain an SNA PU type 2.0 or 2.1 to
support dependent LUs at the host. For example, it could be another
computer running SNAplus2 in a stand-alone configuration.
An example of a node providing PU concentration is shown in Figure 2-1,
“PU Concentration Linking Multiple Downstream HP-UX Workstations
to a Host Computer.”
Figure 2-1 PU Concentration Linking Multiple Downstream HP-UX
Workstations to a Host Computer
When PU concentration is used, all the data transferred between the
host and the downstream computer is routed through the SNAplus2 local
node. This enables a downstream computer to share a host connection
with SNAplus2 or with other downstream computers, instead of
requiring a direct link. For example, you can set up several downstream