Configuring SNAplus2 for Enterprise Extender
Table Of Contents
Configuring SNAplus2 for Enterprise Extender White Paper 34
An End Node can also have a direct connection to another End Node or LEN
node, but CP-CP sessions are never established between the two nodes.
LEN Node
A LEN Node is of type 2.1 node that uses independent LU 6.2 protocols, but
does not support CP-CP sessions. It can be connected to a Network Node or
End Node but does not support APPN functions. A Network Node can provide
routing services for an attached LEN node, enabling the LEN node to participate
in an APPN network without requiring links to be defined between the LEN node
and all of the nodes in the APPN network.
LUs in the APPN network with which the LEN node may want to establish
session
s must be defined to the LEN node as if they reside on the LEN node's
Network Node server. The LEN node establishes sessions with LUs defined to
be contacted through its Network Node Server. The Network Node routes the
session through the APPN network to the node in the network where the LU
actually resides.
LUs on the LEN node must be predefined to the Network Node that serves the
LEN node.
LU resources on LEN nodes (unlike those on End Nodes) cannot be
registered on the Network Node Server by the LEN node.
When a LEN node's only link is to an End Node, the LEN node can communicate
only with
LUs on the End Node through the direct link between the two nodes.
This is because an End Node cannot provide intermediate routing.
Branch Network Node
The Branch Network Node (BrNN) combines the functions of a Network Node
and an End Node. As the name implies, a BrNN can be used to subdivide a
network into a backbone network and attached branch networks.
¾ To the
backbone network, the BrNN appears as an End Node, connected to
its Network Node Server (NNS) in the backbone network.
The nodes in the backbone network are not aware of the nodes within
the bran
ch, reducing the amount of topology information that must be
stored. As the BrNN appears as an End Node and does not receive
topology information from the backbone network (topology information
is transmitted only between Network Nodes) there is a reduction in the
amount of network overhead traffic flowing into the branch network.
The BrNN registers all resourc
es in the branch with its NNS as though
they were located on the BrNN itself. This means that the nodes in the
backbone network can locate resources in the branch without having to
be aware of the separate nodes in the branch.
¾ To the
branch network, the BrNN appears as a Network Node, acting as the
NNS for End Nodes and LEN Nodes in the branch.
High Performance Routing
High Performance Routing (HPR) is an extension of the APPN architecture. HPR
provides the following functions:
¾ Rapid
Transport Protocol (RTP) minimizes processing cycles and storage
requirements for routing network layer packets through intermediate
nodes on a session route.