RFC 2155 (rfc2155) - Page 3 of 124

Definitions of Managed Objects for APPN using SMIv2

RFC 2155        Definitions of Managed Objects for APPN        June 1997


   The directory and routing functions enable an NN to find where an LU
   is located in the network, and calculate the optimal route for the
   session based on the requested class of service (COS).  A network
   node saves the LU information in a directory database, which is built
   from LUs defined locally, LU registration from served end nodes, and
   LUs learned from network searches.

   Each NN maintains a local COS database that assigns a routing weight,
   or relative cost, to each resource for each class of service.  For
   example, the #INTER COS assigns a lower weight to TGs with a greater
   effective capacity, while the #BATCH COS favors TGs with a lower
   relative cost per byte.

   A node saves network topology information (on NNs, VRNs, and TGs
   between them) in a network topology database.  The topology
   information includes state and routing characteristics.  Topology
   information is exchanged between NNs over CP-CP sessions such that
   the database is fully replicated at each NN.  Information on TGs from
   NNs to ENs are kept in a local topology database.  Local topology
   information is shared with other NNs only during the session
   establishment process, to give the NN responsible for route
   calculation the necessary information for end-to- end route
   calculation.

   SNA names such as LU names, CP names, COS names, and mode names can
   be padded with blanks (space characters) in SNA formats.  These
   blanks are nonsignificant.  For example, in a BIND Request Unit (RU)
   a COS name of "#INTER" with a length of 6 is identical to a COS name
   of "#INTER  " with a length of 8.  However, in this MIB,
   nonsignificant blanks are not included by the agent.   Using the COS
   name from the previous example, an agent would return a length of 6
   and the string "#INTER" with no blanks for appnCosName, regardless of
   how it appears in the BIND RU or in internal storage.  The lone
   exception is the all blank mode name, for which the agent returns a
   length of 8 and the string "        " (8 blank spaces).  The MIB
   variables that this applies to are identified by a textual convention
   syntax that also describes this behavior.

   When an SNA name is functioning as a table index, an agent treats
   trailing blanks as significant.  If a management station requests the
   objects from a row with index "#INTER  ", the agent does not match
   this to the row with index "#INTER".  Since an agent has no
   nonsignificant blanks in any of its table indices, the only reason
   for a Management Station to include them would be to start GetNext
   processing at a chosen point in a table.  For example, a GetNext
   request with index "M       " would start retrieval from a table at
   the first row with an 8-character index beginning with "M" or a
   letter after "M".



Clouston & Moore            Standards Track