SIP-MIB

MIB Reference — IPNetwork Monitor · Updated October 06, 2026

All MIBs › SIP-MIB

Organization: IETF Interfaces Working Group

Last Updated: 1994-03-31

Category: IP and Core Protocols, Telephony and VoIP

Description: Manages Session Initiation Protocol (SIP) User Agent entities, covering UA configuration, registration status, and session statistics.

IPNetwork Monitor uses several OIDs from this MIB in network discovery and polling the applicable devices. Start monitoring SIP-MIB with a free 30-day trial of IPNetwork Monitor.

What Is SIP-MIB?

Despite its name, this SIP-MIB (as reflected in its actual description and object set) is the IETF MIB for the SMDS Interface Protocol (RFC 1694's 'SIP'), not the VoIP Session Initiation Protocol -- it defines managed objects for interfaces running SMDS (Switched Multi-megabit Data Service), a legacy WAN service. It is a vendor-neutral, standards-based MIB, so its data covers Level 3/Level 2 SMDS interface counters: addresses received/sent, unrecognized and invalid address counts, and protocol version support. Its monitoring role is centered on interface/protocol performance and fault counters -- tracking error conditions like invalid SMDS address types or unrecognized destination/group addresses that indicate a misconfigured or failing SMDS access line. As an IETF standards MIB it is meant to be used alongside the standard IF-MIB for the underlying physical/link-layer interface it rides on. It would have been deployed on WAN routers/DSU-CSU-style access devices terminating SMDS service in the 1990s-era carrier data networks, as defined by the SIP-MIB RFC (RFC 1694).

IPNetwork Monitor allows you to monitor SNMP objects defined in SIP-MIB. Use the built-in SNMP Monitoring Browser to explore available variables, view their current values and descriptions, and select the objects you want to monitor. You can then create SNMP monitors, configure thresholds, and receive alerts when monitored values change.

Supported Devices

  • vendor-neutral, standards-based MIB, not tied to a specific manufacturer
  • WAN routers/access devices terminating SMDS service

Monitoring Examples

An administrator would poll sipL3Table entries indexed by sipL3Index to check counters like sipL3ReceivedIndividualDAs, sipL3ReceivedGAs, and sipL3SentIndividualDAs against sipL3UnrecognizedIndividualDAs and sipL3UnrecognizedGAs for a given SMDS interface. A rising sipL3Errors or sipL3InvalidSMDSAddressTypes count alongside flat traffic counters would point to an addressing misconfiguration or corrupted SMDS PLCP framing on that access line. sipL3VersionSupport confirms which SIP protocol version the interface is negotiating, useful when troubleshooting interoperability with the carrier's SMDS switch.

What Can Be Monitored

  • SMDS individual/group destination addresses received
  • SMDS addresses sent
  • unrecognized individual/group addresses
  • SMDS protocol errors
  • invalid SMDS address type count
  • SIP protocol version support
Imported Objects

From RFC1213-MIB

ifIndex
mib-2
transmission

From SNMPv2-CONF

MODULE-COMPLIANCE
OBJECT-GROUP

From SNMPv2-SMI

Counter32
Integer32
IpAddress
MODULE-IDENTITY
OBJECT-TYPE

From SNMPv2-TC

TEXTUAL-CONVENTION
TimeStamp

How to Use in IPNetwork Monitor

Example using sipL2ReceivedCounts OID:

Select an SMDS access devices/router as the target host to create a monitor — the SNMP service should be up and running on it. Click New Monitor, then check SNMP Custom on the Favorites tab, click Next, and confirm the host. On the next page, click Select... to open the built-in SNMP MIB Browser and type sipL2ReceivedCounts into the Find box to locate it in the OID tree, selecting the specific row/instance you want to monitor since this is a table column, then select it and click OK. The number of SIP Level 2 PDUs received from the remote system across the SNI. On the monitor's Main parameters page you can set the target's SNMP port (default 161), credentials, polling interval, and other settings — see the SNMP Monitor help for details. On the State conditions and Alerting tabs, configure when the monitor should change state and trigger an alert; since this is a Counter32-type OID, Value bounds is the most useful condition here — trigger an alert if the counter increases sharply between polls relative to its normal baseline, since an unexpected spike often reflects a real change in traffic or activity. Click Finish to create the monitor; you can adjust any parameter later.
OIDs

RFC description

SMDS (Switched Multimegabit Data Service) Interface Protocol MIB (RFC 1694) for monitoring SMDS interface objects on data service networks.

Start monitoring SMDS access devices/routers with a free 30-day trial of IPNetwork Monitor. Import MIBs, browse SNMP OIDs, create custom SNMP monitors, configure alerts, and monitor any SNMP-enabled network device from a single console.

Download SIP-MIB