Visara LINCS Features - Manual (Page 14)

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LINCS Features
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Dynamic Connections
LINCS uses dynamic connections to find other APPN nodes. End nodes using a LINCS node
as their server will dynamically connect, as will nodes on the connection network.
Predefined Circuits
Predefined Circuits are for nodes that cannot be located dynamically; Low Entry Nodes and
Channel/SNA and SDLC links are examples however, links to End Nodes and adjacent NNs
can be predefined. A user can specify the node type or allow LINCS to learn the node type of
the node that initiates communications.
Connection Networks
A connection network increases session performance by allowing end nodes to communicate
directly without the routing services of a network node. LINCS directs the end node to end
node communication, but does not have to be a part of the connection network. To do this the
transport facility must be a “Shared Access Transport Facility” which allows end nodes to
communicate directly i.e. LLC or Frame Relay.
Route Selection
APPN’s dynamic route selection eliminates the complex network definition required by other
protocols. APPN’s route selection separates the search phase from the route selection. First
the requested resource (LU) is located, then a route to the resource is determined.
The path chosen by APPN is based on location, topology information, requested priority and
class-of-service. APPN’s chooses route selection using:
• Class of Service
• Directory Services
• Network Topology
Class of Service
COS routing defines how different types of data will be routed, using paths optimized for that
specific type. All APPN nodes have several predefined classes of service. The COS used is
determined by the mode name used at session establishment time. LINCS supports four standard
mode names, plus the null or blank name. The four standard names correlate to identical COS
names. A name of all blanks correlates to the #CONNECT COS name. The Mode Name is
used to obtain a COS name and transmission priority requirements for the requested session.
A COS name designates a set of definitions used for route selection. LINCS has five standard
predefined COS names, and allows you to define additional COS names. Because COS names
are data objects in LINCS, they may be copied to other LINCS nodes manually or via Central
Site Change Management, a definite advantage for users needing to add COS names or modify
the standard definitions.