Definitions of Managed Objects for APPN using SMIv2
obsoleted by
- rfc-2455 — Definitions of Managed Objects for APPN
Extracted elements (25)
A link station flagged appnLsActOnDemand is advertised in the network topology as active regardless of its actual operational state, so it can be included in route calculations; if selected, it is activated on demand. This avoids penalizing dial-on-demand links in route computation while still allowing their use.
Agents strip non-significant trailing blanks from SNA names in all MIB variables (e.g., '#INTER ' is returned as '#INTER'), because SNA permits blank-padding but SNMP consumers should not need to handle it. The all-blank mode name (8 spaces) is the sole exception, preserved because blank is a meaningful value in that context.
When an SNA name is used as a table index, trailing blanks are treated as significant by the agent, enabling management stations to use blank-padded index values as GetNext starting points without accidentally matching shorter names. Since agents never store nonsignificant trailing blanks, a management station adding them must intend this navigation use.
Earlier SNA implementations permitted '#', '@', and '$' in NetIds and CpNames; this use has been retired but management stations must still accept these characters for backward compatibility with legacy nodes. Agents need not generate them.
Counter discontinuity detection is provided via three TimeStamp objects: appnNodeCounterDisconTime, appnPortCounterDisconTime, and appnLsCounterDisconTime, each recording sysUpTime at the last re-initialization of the respective resource. Management stations must monitor these to detect counter wraps or resets.
When appnLsOperState is active, appnLsMaxSendBtuSize returns the negotiated value—the smaller of the locally configured maximum and the partner's maximum receive BTU length from XID—rather than the locally configured value. When inactive or pending-active, the locally configured value is returned.
appnLsStatusTable records exceptional conditions during link activation, XID exchange, and termination. Each entry captures a timestamp, four sense-data fields (general, end-of-connection, local XID rejection, remote XID rejection), and the specific XID byte (0–65535) and bit (0–7) that caused an XID error. No entries are created for normal activations.
appnLsTable (indexed by link station name) captures per-link configuration (port name, DLC type, dynamic flag, adjacent CP name, TG number, limited-resource and act-on-demand flags), byte/frame traffic counters for XID and data, round-trip delay measurements (current, min, max with timestamp), XID exchange counts, and HPR-specific fields (ANR labels, NCE IDs for CP-CP, Route Setup, and boundary function).
appnNodeHprSupport (and the per-link appnLsHprSup) report HPR capability level via four values: noHprSupport(1), hprBaseOnly/option-set-1400(2), rtpTower/option-set-1401(3), controlFlowsOverRtpTower/option-set-1402(4), mapped from cv4580 byte 9 bits 3–4.
appnPortTable (indexed by appnPortName, 1–10 chars) describes each APPN port's DLC type (IANAifType), port type (leased/switched/sharedAccessFacilities), SIM/RIM support, link station role (primary/secondary/negotiable/abm), maximum receive BTU size (99–32767 bytes), I-frame window size, XID success/failure counters for defined and dynamic link stations, and a RowPointer to DLC-specific MIB information.
AppnTopologyEntryTimeLeft is an INTEGER (0–15) indicating the number of days before an entry is deleted from the topology database. A value of 0 means the entry is being deleted or will be marked for deletion at the next garbage collection cycle.
The APPN MIB module (appnMIB, OID snanauMIB 4 / mib-2 34 4) defines six object groups: appnNode, appnNn, appnLocalTopology, appnDir, appnCos, and appnSessIntermediate, plus appnTraps for SNA/MS alert notification. It covers configuration monitoring, operational statistics, and limited control (port/link activation) but explicitly excludes node configuration, endpoint sessions, DLUR, and HPR management.
The appnCos group defines four tables: appnCosModeTable (mode-to-COS mapping), appnCosNameTable (transmission priority per COS), appnCosNodeRowTable (node weight per COS used in route calculation), and appnCosTGRowTable (TG weight per COS). Together these represent the complete COS database used for session routing.
The appnNn group's topology tables are indexed by FRSN (flow reduction sequence number) so management stations can retrieve only incremental updates: the agent updates the FRSN of any new or changed resource, allowing a station to poll for changes since its last retrieval.
The appnSessIntermediate group includes appnIsInGlobal (controls whether RSCVs and counters are collected), appnIsInTable (active intermediate sessions through this node), and appnIsRtpTable (intermediate sessions running over HPR RTP connections). Deactivating intermediate sessions is a supported management operation.
Section 7 identifies writable objects—primarily appnPortCommand, appnLsCommand (port and link activation/deactivation), and appnNodeNnSafeStoreFreq—as potential targets for misuse that could disrupt network operations. The document recommends applying SNMPv2 security mechanisms to restrict SET access to authorized management stations.
APPN link station operational state (appnLsOperState) has 11 granular states: inactive(1); pending-active states sentConnectOut(2), pendXidExch(3), sendActAs(4), sendSetMode(5), otherPendingActive(6); active(7); pending-inactive states sentDeactAsOrd(8), sentDiscOrd(9), sentDiscImmed(10), otherPendingInact(11). States 2–5 represent the normal activation sequence.
APPN port operational state (appnPortOperState) has four states: inactive(1), pendactive(2), active(3), pendinact(4). Transitions are triggered by management SET commands on appnPortCommand: activate(2), deactivate(1), or recycle(3); GET returns ready(4) until the first SET is processed.
AppnTgDelay encodes signal propagation delay as a 1-byte OCTET STRING using the same scheme as cv47, representing microseconds. Key encoded values include negligible(384/X'4C'), terrestrial(9216/X'71'), packet(147456/X'91'), long(294912/X'99'), and maximum(2013265920/X'FF').
AppnTgEffectiveCapacity encodes TG bandwidth as a 1-byte OCTET STRING using the same floating-point encoding as cv47 byte 7, in units of 300 bits per second. It is an administratively assigned value derived from link bandwidth and maximum load factor.
AppnTgSecurity encodes TG physical security as an INTEGER with seven values: nonsecure(1/X'01'), publicSwitchedNetwork(32/X'20'), undergroundCable(64/X'40'), secureConduit(96/X'60'), guardedConduit(128/X'80'), encrypted(160/X'A0'), guardedRadiation(192/X'C0'). COS definitions reference acceptable TG security values for routing.
SnaControlPointName encodes a fully qualified SNA CP name as a 3–17 byte OCTET STRING in NetId.CpName form, where each component is 1–8 uppercase ASCII alphanumeric characters with the first character a letter and no trailing blanks. Management stations must also accept the legacy characters '#', '@', '$' for backward compatibility.
SnaModeName encodes an SNA mode name as a 0–8 byte OCTET STRING; trailing blanks are prohibited except for the all-blank mode name, which is returned as exactly 8 space characters. A zero-length string indicates the mode name is unavailable.
SnaNodeIdentification encodes the 4-byte SNA Node Identification (XID bytes 2–5) as exactly 8 ASCII-encoded uppercase hexadecimal characters. The first 3 hex digits are the product block number; the last 5 are the administratively assigned ID. The value 'bbb00000' signals a non-unique ID number on some implementations.
SnaSenseData encodes SNA error sense data as exactly 8 ASCII-encoded uppercase hexadecimal characters ('0'–'9', 'A'–'F'). Eight '0' characters indicates no SNA error sense data is available.