HP-UX SNAplus2 General Information (October 1998)

Chapter 3 55
SNAplus2 Networking Solutions
Adding APPN Capability
The original SNAplus2 servers can connect simultaneously to both
APPN and pre-APPN nodes. The server provides PU concentration
functionality to downstream LUs. PU concentration enables host-based
SNA applications to be run on the APPN network, while reducing the
number of links required to the host in a fashion that is completely
transparent-both to the host and to the downstream LU. This function
enables legacy applications to run on the APPN network without
modification, and reduces the connectivity requirements for
communication with the host from the APPN network.
In addition, the financial services division writes new distributed
applications that run on the SNAplus2 network nodes and end nodes in
the APPN part of the network. The APPN network enables new
machines to access the applications automatically as they are connected
to the network, without requiring reconfiguration at the host for every
new computer that is added.
These new applications make use of the increased processing power that
is available on local workstations, without increasing the volume of the
traffic to the host.
By doing more processing locally, this configuration decreases the
demand for host processing so that the remaining corporate central
processing can be done more quickly.
As the APPN part of the network grows, SNAplus2 DLUR functionality
(running in conjunction with DLUS on the host) supports corporate
back-level applications (such as 3270) transparently across the APPN
network. DLUR provides a migration path from subarea SNA
applications to APPN.