HP-UX SNAplus2 General Information (October 1998)

22 Chapter 1
SNA Networking
Mixed SNA Networks
Mixed SNA Networks
Although APPN networks do not require a host to control resources in
the network, hosts often participate in APPN networks. APPN has been
implemented on many host platforms, enabling the hosts to perform as
network nodes in the APPN network; at the same time, the host provides
an SSCP to control subarea SNA functions.
Many SNA networks reflect their history, containing elements of both
subarea SNA and APPN. The backbone of the network is built from
network nodes that must bridge the gap between a dependent LU and
the facilities on the host.
The following additional services are required to achieve this:
Dependent LU server (DLUS)
On the host, DLUS provides access to the old SSCP
functions and acts as an interface to the APPN
network.
Dependent LU requester (DLUR)
On a network node or end node, DLUR provides
passthrough function to the host for dependent LUs.
This combination of DLUR and DLUS (generally known simply as
DLUR) enables dependent LU traffic to be transported over the APPN
backbone. Existing SNA applications that use dependent LUs can be
retained without modification, while taking advantage of APPN's
network management, dynamic resource location, and route selection
capabilities. In this way, DLUR provides a useful migration path from
subarea SNA to APPN.