# CUCM call management records (CMR) fields and the CDR relation

Canonical: https://warmtransfer.net/knowledge/cucm-call-management-records

Last verified: 2026-09-24

Cisco Unified Communications Manager (CUCM) Call Management Records (CMRs), also called call diagnostic records, store diagnostic information about the quality of streamed audio and video for a call[^17][^1]. In contrast, Call Detail Records (CDRs) record endpoint, routing, and call control details[^17].

## How it works

On a fresh CUCM installation, CDRs are enabled by default, while CMRs are disabled by default[^18]. The generation of CMRs is governed clusterwide by the Call Diagnostics Enabled service parameter, which provides 3 configuration options: Disabled, Enabled Only When CDR Enabled Flag is True, and Enabled Regardless of CDR Enabled Flag[^3]. Under the Enabled Only When CDR Enabled Flag is True setting, CUCM produces CMRs only if the CDR Enabled Flag parameter is True; setting it to Enabled Regardless of CDR Enabled Flag produces CMRs regardless of the CDR flag setting[^2]. When Call Diagnostics Enabled is set to Disabled, the CAR dashboard flags that the setting is disabled and warns that QoS information will not be collected for calls[^8].

When enabled, CUCM creates a CMR for each call leg when a user disconnects at their device, generating 1 CMR for each IP phone or MGCP gateway involved in the call[^35][^39]. The endpoints listed as supporting CMRs are Cisco Unified IP Phones and MGCP gateways[^49]. In addition, starting in CUCM 12.5, CMRs can be generated for SIP trunk calls as well as internal calls without introducing new CMR fields[^48]. For SIP trunk calls, Cisco Unified Border Element (CUBE) delivers call quality metrics in a P-RTP-Stat header within a BYE message or a 200 OK response to a BYE, which CUCM uses to update the corresponding CMR[^47].

Depending on the call flow, multiple CMRs can be generated for a single CDR[^32]. For example, SCCP endpoints generate multiple CMRs across hold-and-resume events, with the count determined by how many times the call is placed on hold[^42].

## The CDR relation and join keys

In every CUCM CMR, the cdrRecordType field contains a constant value of 2; CDRs use a value of 1 to denote an end record, while the value 0 for a start record remains unused[^40].

The Global Call ID is made of globalCallID_callManagerId and globalCallId_callId, and all CDR and CMR records associated with a standard call carry the same Global Call ID[^23]. The full unique call key defined in the CDR specification consists of globalCallId_ClusterId plus globalCallId_CMId plus globalCallId_CallId, and the CMR also carries a globalCallId_ClusterId text field[^11]. Each CMR contains a callIdentifier integer identifying the call leg to which that CMR pertains[^5]. In the CAR 12.5(1) documentation, finding an originating or destination CMR of a CDR is performed by leg ID: a CMR whose leg ID matches the CDR's Orig leg ID is the origination CMR and one matching the Dest leg ID is the destination CMR[^28]. In the CDR, origLegCallIdentifier identifies the originating leg and destLegIdentifier identifies the terminating leg, each value being unique within a cluster, though destLegIdentifier may be 0[^29].

In an SCCP-to-SCCP call example documented by Cisco, 2 CMRs are produced, 1 per phone, both sharing globalCallID_callManagerId 1 and globalCallId_callId 96004, while carrying different callIdentifier values of 28141535 and 28141536[^20].

## CMR field reference

Besides the join keys, a CMR carries nodeId (the cluster node that generated it), directoryNumber and directoryNumberPartition, deviceName, and pkid (a database unique identifier)[^24]. The CMR dateTimeStamp field is an integer giving the approximate time the device goes on hook[^16]. The CMR duration field gives the audio session length in seconds and is filled only for SIP phones[^19].

### Audio and transmission metrics

The CMR audio counters count RTP data packets and RTP payload octets, defaulting to 0[^41]:

| Field | Description |
| --- | --- |
| `numberPacketsSent` | Count of RTP data packets transmitted (defaults to 0)[^41]. |
| `numberOctetsSent` | RTP payload octets transmitted (defaults to 0)[^41]. |
| `numberPacketsReceived` | Count of RTP data packets received (defaults to 0)[^41]. |
| `numberOctetsReceived` | RTP payload octets received (defaults to 0)[^41]. |
| `numberPacketsLost` | Total RTP data packet loss count during reception[^38]. |
| `jitter` | Statistical variance of RTP packet interarrival time in milliseconds (unsigned integer, defaults to 0)[^25]. |
| `latency` | Estimated network latency in milliseconds; omitted on certain phone loads such as SIP 9.2.1 and 9.2.2[^27]. |

### Voice quality metrics (varVQMetrics)

The varVQMetrics field is a text field holding a variable number of voice quality metrics as name=value pairs separated by semicolons, for example MLQK, MLQKav, MLQKmn, MLQKmx, MLQKvr, CCR, ICR, ICRmx, CS and SCS[^51].

* `MLQK`: Estimate of the MOS score over the last 8 seconds of the received signal, using a scale from 1 (poor voice quality) to 5 (very good voice quality)[^30][^33]. Maximum MOS LQK scores depend on codec, reaching 4.5 for G.711 and G.722, and 3.8 for G.729A/AB[^12]. Cisco phone guidance treats MOS LQK changes of about 0.2 or more that persist in calls longer than 30 seconds as significant[^45].
* `MLQKmn` and `MLQKmx`: Minimum and maximum MOS score estimates since the call began[^30].
* `MLQKav`: Running average MOS score since the call began[^30].
* `CCR`: Cumulative ratio of concealment time over speech time since call start[^13]. A Conceal Ratio of 0 means the IP network is delivering frames and packets on time with no loss[^53].
* `ICR`: Concealment ratio over the last 3 seconds of active speech[^13].
* `ICRmx`: Maximum concealment ratio seen during the call[^13].
* `CS`: Conceal Secs, marking the time during which some concealment is observed[^15].
* `SCS`: Severely Conceal Secs, marking the time during which a significant amount of concealment is observed[^15]. Phone documentation defines a severely concealed second as a second in which the DSP plays more than 5 percent concealment frames[^43].

These voice quality metrics reflect frame loss only, not noise, distortion or echo[^53].

### Video, session, and peripheral fields

CMRs carry video metrics for up to 2 video channels, including videoContentType (main, speaker or slides), duration, packet and octet counts, lost packets, jitter, round-trip time, one-way delay, and Cisco transmission and reception metrics strings[^52].

The CMR also ends with localSessionID and remoteSessionID (up to 127 characters each) and headset fields SN (headset serial number) and Metrics (headset diagnostics up to 600 characters whose subfields are not validated)[^44].

## CAR grading and file extraction

In CAR, administrators can define lost packet, jitter, and latency ranges that categorize call voice quality as Good, Acceptable, Fair or Poor; calls failing to match any category are classified NA[^10]. By default, CAR configures jitter ranges as Good 0 to 20, Acceptable 21 to 100, Fair 101 to 150 and Poor 151 to infinity[^6]. CAR ships no default latency ranges for its QoS grades, though not all 3 QoS parameters may be NA[^9].

CDR repository flat files carry a type tag in the file name that separates CDR from CMR files (e.g., `cmr_Cluster1_02_200404061011_6125`)[^22]. Administrators can export CDRs, CMRs, or both in CSV format across a chosen date range through CDR > Export CDR/CMR in CAR[^21].

## See also

* [Cucm call detail records](https://warmtransfer.net/knowledge/cucm-call-detail-records)
* [Cube sip trunk call quality](https://warmtransfer.net/knowledge/cube-sip-trunk-call-quality)

## Applicability

The deployment model is not covered by the sources below.

## What remains uncertain

The following items are not covered by the sources below:
* Cisco MOS threshold for poor voice quality in CMR data is not covered by the sources below.
* Release 15 statement that CMR callIdentifier equals CDR origLegCallIdentifier or destLegIdentifier is not covered by the sources below.
* CMR CSV column order and header names in CDR Repository flat files versus the CAR export are not covered by the sources below.
* Meaning of MLQK=0.0000 in CMR examples (not measured versus zero score) is not covered by the sources below.
* Units of CAR default lost-packet ranges (count or percent) are not covered by the sources below.
* CMR count per CDR for SIP phones on hold and resume and for transfer and conference is not covered by the sources below.
* MLQKvr definition is not covered by the sources below.
* CMR dateTimeStamp epoch and time zone are not covered by the sources below.

## Sources

[^1]: The Release 15 Call Management Records chapter describes CMRs as storing the quality of the streamed audio and video of the call. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Call Management Records](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01100.html), Call Management Records chapter, CMR Processing. Checked 2026-09-22.
[^2]: With Call Diagnostics Enabled set to Enabled Only When CDR Enabled Flag is True, CUCM generates CMRs only while the CDR Enabled Flag service parameter is True; with Enabled Regardless of CDR Enabled Flag it generates CMRs whatever that flag says. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Call Management Records](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01100.html), Call Management Records chapter, Call Diagnostics Enabled service parameter description. Checked 2026-09-22.
[^3]: The Call Diagnostics Enabled service parameter controls CMR generation and has three valid values: Disabled, Enabled Only When CDR Enabled Flag is True, and Enabled Regardless of CDR Enabled Flag. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Call Management Records](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01100.html), Call Management Records chapter, Call Diagnostics Enabled service parameter description. Checked 2026-09-22.
[^4]: The CMR callIdentifier is expected to equal the CDR origLegCallIdentifier for the originating endpoint's CMR and the CDR destLegIdentifier for the terminating endpoint's CMR (inferred). Source: [Cisco Unified CDR Analysis and Reporting Administration Guide, Release 12.5(1) - CDR Search](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/service/12_5_1/Car/cucm_b_cdr-analysis-reporting-admin-guide-1251/cucm_b_cdr-analysis-reporting-admin-guide-1251_chapter_011100.html), CDR Search chapter, section CDR and CMR Dump Tables; read with Release 15 CDR Field Descriptions rows origLegCallIdentifier and destLegIdentifier. Checked 2026-09-22.
[^5]: The CMR callIdentifier field (positive integer) identifies the call leg to which that CMR pertains. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01101.html), CMR Field Descriptions table, row callIdentifier. Checked 2026-09-22.
[^6]: CAR's default jitter ranges are Good 0 to 20, Acceptable 21 to 100, Fair 101 to 150 and Poor 151 to infinity. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Initial Setup](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01011.html), Initial Setup chapter, section Define QoS Values, default values table. Checked 2026-09-22.
[^7]: CAR's default lost-packet ranges are Good 0.00 to 15.00, Acceptable 15.01 to 30.00, Fair 30.01 to 45.00 and Poor 45.01 to infinity. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Initial Setup](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01011.html), Initial Setup chapter, section Define QoS Values, default values table. Checked 2026-09-22.
[^8]: When the clusterwide Call Diagnostics Enabled flag is disabled, the CAR dashboard shows that the flag is disabled and that QoS information will not be generated on calls. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Initial Setup](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01011.html), Initial Setup chapter, section Log On to CAR. Checked 2026-09-22.
[^9]: CAR ships no default latency ranges for its QoS grades, and not all three QoS parameters may be NA. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Initial Setup](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01011.html), Initial Setup chapter, section Define QoS Values. Checked 2026-09-22.
[^10]: CAR grades call voice quality as Good, Acceptable, Fair or Poor from administrator-configurable ranges for lost packets, jitter and latency, and a call matching no category is classified NA. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Initial Setup](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01011.html), Initial Setup chapter, section Define QoS Values. Checked 2026-09-22.
[^11]: The CDR field chapter defines the unique call key as globalCallId_ClusterId plus globalCallId_CMId plus globalCallId_CallId, and the CMR also carries a globalCallId_ClusterId text field. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager Release 15 and SUs, CDR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01010.html), CDR Field Descriptions table, row globalCallId_ClusterId. Checked 2026-09-22.
[^12]: Cisco phone documentation states that MOS LQK maximum scores depend on codec: 4.5 for G.711 and G.722 and 3.8 for G.729A/AB. Source: [Cisco Wireless IP Phone 8821 and 8821-EX Administration Guide for Cisco Unified Communications Manager - Maintenance](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cuipph/8821/english/adminguide/w88x_b_wireless-8821-8821ex-admin-guide/w88x_b_wireless-8821-8821ex-admin-guide_chapter_01000.html), Maintenance chapter, section Voice Quality Monitoring. Checked 2026-09-22.
[^13]: CCR is the cumulative ratio of concealment time over speech time since call start, ICR is the same ratio over the last 3 seconds of active speech, and ICRmx is the maximum concealment ratio seen during the call. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01101.html), K-Factor Data table, rows CCR, ICR, ICRmx. Checked 2026-09-22.
[^14]: Cisco phone guidance says Conceal Ratio changes should indicate greater than 3 percent frame loss. Source: [Cisco Wireless IP Phone 8821 and 8821-EX Administration Guide for Cisco Unified Communications Manager - Maintenance](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cuipph/8821/english/adminguide/w88x_b_wireless-8821-8821ex-admin-guide/w88x_b_wireless-8821-8821ex-admin-guide_chapter_01000.html), Maintenance chapter, section Voice Quality Monitoring. Checked 2026-09-22.
[^15]: CS (Conceal Secs) is the time during which some concealment is observed and SCS (Severely Conceal Secs) is the time during which a significant amount of concealment is observed. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01101.html), K-Factor Data table, rows CS and SCS. Checked 2026-09-22.
[^16]: The CMR dateTimeStamp field is an integer giving the approximate time the device goes on hook. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01101.html), CMR Field Descriptions table, row dateTimeStamp. Checked 2026-09-22.
[^17]: CUCM CMRs, also called call diagnostic records, hold diagnostic information about the quality of the streamed audio of a call, while CDRs hold endpoint and call control or routing information. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Call Details Records Overview](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01000.html), Call Details Records Overview chapter, introductory description of CDRs and CMRs. Checked 2026-09-22.
[^18]: On a new CUCM installation CDRs are enabled by default and CMRs are disabled by default. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Call Details Records Overview](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01000.html), Call Details Records Overview chapter, default status statement. Checked 2026-09-22.
[^19]: The CMR duration field gives the audio session length in seconds and is filled only for SIP phones. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Examples](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01110.html), CMR Examples chapter, Example 1 SCCP to SCCP Phone, note after the records. Checked 2026-09-22.
[^20]: Cisco's SCCP-to-SCCP CMR example shows two CMRs, one per phone, with the same globalCallID_callManagerId (1) and globalCallId_callId (96004) and different callIdentifier values (28141535 and 28141536). Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Examples](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01110.html), CMR Examples chapter, Example 1 SCCP to SCCP Phone. Checked 2026-09-22.
[^21]: CAR exports CDRs, CMRs or both for a chosen date range from CDR > Export CDR/CMR, and the dump is in CSV format. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Export CDRs and CMRs](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_0101.html), Export CDRs and CMRs chapter, procedure. Checked 2026-09-22.
[^22]: CDR repository flat files carry a type tag in the file name that separates CDR from CMR files, as in the example cmr_Cluster1_02_200404061011_6125. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Call Details Records Overview](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01000.html), Call Details Records Overview chapter, file name format. Checked 2026-09-22.
[^23]: The Global Call ID is made of globalCallID_callManagerId and globalCallId_callId, and all CDR and CMR records associated with a standard call carry the same Global Call ID. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01101.html), CMR Field Descriptions table, rows globalCallID_callManagerId and globalCallId_callId. Checked 2026-09-22.
[^24]: Besides the join keys a CMR carries nodeId (the cluster node that generated it), directoryNumber and directoryNumberPartition, deviceName and pkid (a database unique identifier). Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01101.html), CMR Field Descriptions table, rows nodeId, directoryNumber, pkid, directoryNumberPartition, deviceName. Checked 2026-09-22.
[^25]: The CMR jitter field estimates the statistical variance of RTP packet interarrival time in milliseconds as an unsigned integer, default 0. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01101.html), CMR Field Descriptions table, row jitter. Checked 2026-09-22.
[^26]: A join across exports from more than one cluster should include globalCallId_ClusterId alongside the two Global Call ID columns, because callManagerId and callId are only described as unique within a cluster's own numbering (inferred). Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager Release 15 and SUs, CDR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01010.html), CDR Field Descriptions table, rows globalCallID_callManagerId and globalCallId_ClusterId. Checked 2026-09-22.
[^27]: The CMR latency field is an estimate of network latency in milliseconds, but it is not populated for all phone loads; Cisco cites SIP 9.2.1 and 9.2.2 as loads that do not show latency. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01101.html), CMR Field Descriptions table, row latency and its note. Checked 2026-09-22.
[^28]: The 12.5(1) CAR guide says the origination or destination CMR of a CDR is found by leg ID: a CMR whose leg ID matches the CDR's Orig leg ID is the origination CMR and one matching the Dest leg ID is the destination CMR. Source: [Cisco Unified CDR Analysis and Reporting Administration Guide, Release 12.5(1) - CDR Search](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/service/12_5_1/Car/cucm_b_cdr-analysis-reporting-admin-guide-1251/cucm_b_cdr-analysis-reporting-admin-guide-1251_chapter_011100.html), CDR Search chapter, section CDR and CMR Dump Tables. Checked 2026-09-22.
[^29]: In the CDR, origLegCallIdentifier identifies the originating leg and destLegIdentifier the terminating leg, and each value is unique within a cluster; destLegIdentifier may be 0. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager Release 15 and SUs, CDR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01010.html), CDR Field Descriptions table, rows origLegCallIdentifier and destLegIdentifier. Checked 2026-09-22.
[^30]: In the K-factor data MLQK is an estimate of the MOS score over the last 8 seconds of the received signal; MLQKmn and MLQKmx are the minimum and maximum since the call began and MLQKav is the running average since the call began. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01101.html), K-Factor Data table, rows MLQK, MLQKmn, MLQKmx, MLQKav. Checked 2026-09-22.
[^31]: MLQKvr appears in the varVQMetrics examples (for example MLQKvr=0.95, or empty in a SIP example) but the K-Factor Data table gives it no definition. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01101.html), K-Factor Data table (absence) and varVQMetrics example string. Checked 2026-09-22.
[^32]: Depending on the call scenario more than one CMR can exist for each CDR, and the number written varies by call type and scenario. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Call Details Records Overview](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01000.html), Call Details Records Overview chapter, CDR and CMR description. Checked 2026-09-22.
[^33]: The K-factor MOS scores in the CMR use a scale from 1 (poor voice quality) to 5 (very good voice quality). Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01101.html), K-Factor Data section, description of MOS measurements. Checked 2026-09-22.
[^34]: The fetched Cisco sources give no absolute MOS pass or fail threshold for CMR voice quality: CAR grades on jitter, lost packets and latency, and the phone guidance recommends baselines and relative changes (inferred). Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Initial Setup](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01011.html), Initial Setup chapter, section Define QoS Values; read with the 8821 Voice Quality Monitoring section. Checked 2026-09-22.
[^35]: When CMRs are enabled, CUCM writes one CMR for each IP phone involved in the call or for each MGCP gateway, so each endpoint in the call produces its own CMR. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Call Management Records](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01100.html), Call Management Records chapter, CMR Processing. Checked 2026-09-22.
[^36]: The Release 15 CDR overview states that the CDR records relate to the CMR records by way of two GlobalCallID columns: Global CallID callManagerId and GlobalCallID Called; the second name is most likely a typo for globalCallID_callId, which the field tables and a later passage in the same guide use (inferred). Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Call Details Records Overview](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01000.html), Call Details Records Overview chapter, sentence on how CDR records relate to CMR records. Checked 2026-09-24.
[^37]: The Release 15 CDR overview names the CMR-to-CDR join columns as Global CallID callManagerId and GlobalCallID Called; the second name is most likely a typo for globalCallID_callId, which the field tables use (inferred). Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Call Details Records Overview](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01000.html), Call Details Records Overview chapter, sentence on how CMR records relate to CDR records. Checked 2026-09-22.
[^38]: numberPacketsLost in a CMR is the total number of RTP data packets lost since the beginning of reception, a count rather than a percentage. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01101.html), CMR Field Descriptions table, row numberPacketsLost. Checked 2026-09-22.
[^39]: CUCM generates a CMR for each call leg when the user disconnects the call from the user device. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01101.html), CMR Field Descriptions chapter, introductory text. Checked 2026-09-22.
[^40]: In a CUCM CMR the cdrRecordType field is always 2; value 1 marks an end call detail record (CDR) and value 0 (start record) is not used. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01101.html), CMR Field Descriptions table, row cdrRecordType. Checked 2026-09-22.
[^41]: The CMR audio counters numberPacketsSent, numberOctetsSent, numberPacketsReceived and numberOctetsReceived count RTP data packets and RTP payload octets and default to 0. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01101.html), CMR Field Descriptions table, rows numberPacketsSent to numberOctetsReceived. Checked 2026-09-22.
[^42]: For hold and resume calls on SCCP devices CUCM generates multiple CMRs, the number depending on how many times the call is put on hold. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Call Management Records](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01100.html), Call Management Records chapter, CMR Processing. Checked 2026-09-22.
[^43]: Cisco IP phone documentation defines a severely concealed second as a second in which the DSP plays more than five percent concealment frames. Source: [Cisco IP Conference Phone 8832 Administration Guide for Cisco Unified Communications Manager - Maintenance](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cuipph/8832/english/adminguide/cs88_b_conference-8832-admin-guide-cucm/cs88_b_conference-8832-admin-guide-cucm_chapter_01011.html), Maintenance chapter, section Voice Quality Monitoring. Checked 2026-09-22.
[^44]: The Release 15 CMR also ends with localSessionID and remoteSessionID (up to 127 characters each) and headset fields SN (headset serial number) and Metrics (headset diagnostics up to 600 characters whose subfields are not validated). Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01101.html), CMR Field Descriptions table, rows localSessionID, remoteSessionID, SN, Metrics. Checked 2026-09-22.
[^45]: Cisco's phone guidance treats MOS LQK changes of about 0.2 or more that persist in calls longer than 30 seconds as significant, and advises using the metrics as a baseline for comparison. Source: [Cisco Wireless IP Phone 8821 and 8821-EX Administration Guide for Cisco Unified Communications Manager - Maintenance](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cuipph/8821/english/adminguide/w88x_b_wireless-8821-8821ex-admin-guide/w88x_b_wireless-8821-8821ex-admin-guide_chapter_01000.html), Maintenance chapter, section Voice Quality Monitoring, troubleshooting guidance. Checked 2026-09-22.
[^46]: Cisco technote 214152 says SIP trunk CMR generation is not supported for Session Management Edition call flows. Source: [CMR Enhancement in CUCM 12.5](https://www.cisco.com/c/en/us/support/docs/unified-communications/unified-communications-manager-callmanager/214152-cmr-enhancement-in-cucm-12-5.html), Technote 214152, limitations. Checked 2026-09-22.
[^47]: CUBE sends call statistics in a P-RTP-Stat header in a BYE or in the 200 OK to a BYE, and CUCM uses it to update CMRs for SIP trunk calls. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Call Management Records](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01100.html), Call Management Records chapter, SIP trunk CMR text. Checked 2026-09-22.
[^48]: From CUCM 12.5 CMRs can be generated for calls over SIP trunks as well as internal calls, with no new CMR fields added for the feature. Source: [CMR Enhancement in CUCM 12.5](https://www.cisco.com/c/en/us/support/docs/unified-communications/unified-communications-manager-callmanager/214152-cmr-enhancement-in-cucm-12-5.html), Technote 214152, feature overview. Checked 2026-09-22.
[^49]: The Release 15 overview lists Cisco Unified IP Phones and MGCP gateways as the endpoints that support CMRs. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Call Details Records Overview](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01000.html), Call Details Records Overview chapter, supported endpoints sentence. Checked 2026-09-22.
[^50]: The Release 15 CDR overview states that with the Call Diagnostics service parameter set to True the system generates up to two CMRs for each call; this conflicts with the statement that SCCP hold and resume produces multiple CMRs per hold (disputed). Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Call Details Records Overview](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01000.html), Call Details Records Overview chapter, sentence on the Call Diagnostics service parameter. Checked 2026-09-22.
[^51]: varVQMetrics is a text field holding a variable number of voice quality metrics as name=value pairs separated by semicolons, for example MLQK, MLQKav, MLQKmn, MLQKmx, MLQKvr, CCR, ICR, ICRmx, CS and SCS. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01101.html), CMR Field Descriptions table, row varVQMetrics and its example. Checked 2026-09-22.
[^52]: CMRs carry video metrics for up to two video channels, including videoContentType (main, speaker or slides), duration, packet and octet counts, lost packets, jitter, round-trip time, one-way delay and Cisco transmission and reception metrics strings. Source: [Call Reporting and Billing Administration Guide for Cisco Unified Communications Manager, Release 15 and SUs - CMR Field Descriptions](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/callReportingBillingAdmin/15/cucm_b_reporting-billing-administration-guide-15/cucm_b_reporting-and-billing-administration-guide_chapter_01101.html), CMR Field Descriptions table, rows videoContentType through videoTransmissionMetrics_channel2. Checked 2026-09-22.
[^53]: A Conceal Ratio of zero means the IP network is delivering frames and packets on time with no loss, and the voice quality metrics reflect frame loss only, not noise, distortion or echo. Source: [Cisco IP Conference Phone 8832 Administration Guide for Cisco Unified Communications Manager - Maintenance](https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cuipph/8832/english/adminguide/cs88_b_conference-8832-admin-guide-cucm/cs88_b_conference-8832-admin-guide-cucm_chapter_01011.html), Maintenance chapter, section Voice Quality Monitoring and Voice Quality Troubleshooting Tips table. Checked 2026-09-22.