Definitions of Managed Objects for Extended Border Node
Extracted elements (20)
EBNs were introduced to allow partitioning of large APPN networks into subnets by blocking topology information exchange and controlling directory search forwarding, addressing the scalability problem of full topology propagation to all network nodes and the privacy problem in multi-enterprise networks.
The ebnCosMapTable intentionally returns live operational COS mappings rather than user-defined initial mappings, because the EBN's actual mapping is determined by multiple factors beyond user configuration; querying effective mappings is more operationally useful.
The MIB explicitly does not support EBN configuration, session initiation failure history, Peripheral Border Node (PBN) management, or traps, on grounds that PBN is not expected to be widely implemented and APPN MIB alertTrap can reference EBN MIB objects via VariablePointer.
Entries in ebnDirTable, ebnIsRscvTable, and hbnIsInTable are designed to be in one-to-one correspondence with entries in the APPN MIB's appnDirTable and appnIsInTable respectively, using identical index values to allow cross-table correlation.
Subnetwork boundaries in EBN deployments can occur either where adjacent nodes have different NETIDs or where nodes with the same NETID are configured to enforce a boundary; the SNANAU APPN MIB appnNnTopology group identifies these boundaries, which the EBN MIB then extends.
Authentication of received SNMP requests and controlled access to management information SHOULD be employed in network environments where EBN MIB data is considered sensitive.
Five object groups are unconditionally mandatory for compliance: ebnDirectoryGroup, ebnIsRscvGroup, ebnDirectoryConfigGroup, ebnCosMappingGroup, and ebnSubnetRoutingListGroup. The hbnIsInGroup is mandatory only for HPR extended border nodes.
The EBN MIB module (OID snanauMIB 7) defines six object groups for monitoring APPN Extended Border Node capabilities: ebnDir, ebnIsRscv, ebnDirConfig, ebnCos, ebnSubnetRoutingList, and hbn.
The ebnCosMapTable, indexed by ebnCosMapCpName and ebnCosMapNonNativeCos, maps non-native COS values to native COS values. The table reflects the COS mappings the EBN is actually performing at query time, not the initial user-defined mappings.
The ebnDirConfig group exposes three read-only scalars: ebnSearchCacheTime (minutes to retain multi-subnet search results), ebnMaxSearchCache (maximum cached entries), and ebnDefaultSubnetVisitCount (default maximum subnetworks a LOCATE may traverse). A value of 0 for the first two indicates no implementation-defined limit.
The ebnDirTable is a one-to-one extension of the APPN MIB appnDirTable, indexed by ebnDirLuName, adding ebnDirSubnetAffiliation to classify each LU as native(1), nonNative(2), or subarea(3).
The ebnIsRscvTable is a sparse extension of appnIsInTable, indexed by ebnIsRscvCpName and ebnIsRscvPcid, providing the outgoing RSCV (ebnIsRscvDestinationRoute) and COS name (ebnIsRscvDestinationCos) used toward the SLU for sessions crossing ISTGs.
The ebnSearchTable, indexed by ebnSearchLuName and ebnSearchIndex, enumerates the configured ordered list of control points to which an EBN forwards LOCATE searches. Special CP name values '*', '*SELF', and '*EBNS' indicate dynamic, self-search, and all-native-EBN behaviors respectively.
The ebnSubnetSearchTable, indexed by ebnSubnetSearchLuName (supporting explicit, partial wildcard 'ccc*', or full wildcard '*' names), holds per-LU routing list characteristics including ebnSubnetSearchDynamics (none/limited/full) and ebnSubnetSearchOrdering (priority/defined).
The hbnIsInTable is a sparse extension to appnIsInTable for HPR Extended Border Node sessions with back-to-back RTP connections. It provides hbnIsInRtpNceId (NCE ID toward SLU, SIZE 1..8 octets) and hbnIsInRtpTcid (TCID toward SLU, SIZE 8 octets) for the second RTP connection.
The SnaNAUWildcardName textual convention (DisplayString SIZE 1..17) defines three forms for network NAU names: explicit (no '*'), partial wildcard ('ccc*' with 1–16 leading characters), and full wildcard ('*' alone).
The EBN MIB contains no read-write objects and no passwords or user data, but network configuration and usage information may be considered corporate assets; enterprises may wish to restrict SNMP access to most MIB objects. Authentication (RFC 2274) and access control (RFC 2275) mechanisms are referenced.
ebnIsRscvDestinationRoute is an OCTET STRING of SIZE 0..255 encoding the Route Selection Control Vector (RSCV, type x'2B') used toward the SLU side of an EBN-crossed session.
ebnIsRscvPcid is an 8-octet OCTET STRING carrying the procedure correlation identifier (PCID) of a session; combined with ebnIsRscvCpName it uniquely identifies the session and correlates with the corresponding appnIsInTable entry.
hbnIsInPcid is an 8-octet OCTET STRING; together with hbnIsInFqCpName it indexes the hbnIsInTable and correlates with the appnIsInTable entry when both fields match their appnIsIn counterparts.