HP UX SNAplus2 manual Class of Service

SNA Terms and Concepts

Basic SNA Concepts

Class of Service

Class of service (COS) is a definition of the transport network (data link control and path control) characteristics—such as route security, transmission priority, and bandwidth—that the local node can use to establish a particular session. The COS definition assigns relative values to factors such as acceptable levels of security, cost per byte, cost per connect-time, propagation delay, and effective capacity.

In a subarea network, a COS is derived from the mode associated with a session, as defined in the host system.

APPN network nodes use the COS to compute session routes between independent LUs. For more information about session routing in APPN networks, see “Session Routing”.

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