# Glossary: Call Detail Records (CDR)

### Definition

Call detail records, or CDR for short, are the foundation of subscriber billing activities by telecom service providers. They are data records containing call-related information such as:

* Incoming Network
* Outgoing Network
* Calling number
* Called number
* Start time
* End Time

### TelcoBridges and call detail records

TelcoBridges [TMG800](https://docs.telcobridges.com/wiki/TMG800), [TMG3200](https://docs.telcobridges.com/wiki/TMG3200), [TMG7800](https://docs.telcobridges.com/wiki/TMG7800) and [ProSBC](https://docs.telcobridges.com/wiki/ProSBC) products support the generation of call detail records in [text](https://prosbcdocs.telcobridges.com/configuration-details/configuration-by-web-portal-category/call-detail-records-cdr/cdr-variables) format. They also support the ability to export call detail records to a [RADIUS](https://prosbcdocs.telcobridges.com/appendices/appendix-a-glossary/glossary-radius) server for accounting purposes. Both methods can be used simultaneously.

[Text CDRs ](https://prosbcdocs.telcobridges.com/configuration-details/configuration-by-web-portal-category/call-detail-records-cdr/cdr-variables)are stored locally on the devices and must be extracted from the system either manually, or automatically.

If the network supports [RADIUS](https://prosbcdocs.telcobridges.com/appendices/appendix-a-glossary/glossary-radius), this method is preferred as each record will be sent in a timely manner to an external database for storage.

<figure><img src="https://docs.telcobridges.com/w/images/thumb/8/8b/CDR_High-level_drawing_v2.bmp/686px-CDR_High-level_drawing_v2.bmp.png" alt=""><figcaption></figcaption></figure>

### Call Detail Records Generation

TelcoBridges CDRs are generated on a per-leg bases when the call is answered and when the call is terminated.

In the cases illustrated below:

Id is a 128 bits unique identifier for all the records of a same call.

* h323-conf-id for RADIUS and @{SessionId} for Text CDR

'*Original Id is a 128 bits unique identifier used for Call Transfer records. Each call transfer outgoing legs has its own unique Id with its Original Id* associated call legs (incoming+outgoing).

* h323-incoming-conf-id for RADIUS and @{OriginalSessionId} for Text CDR

#### Case 1: Call Answered

<figure><img src="https://docs.telcobridges.com/w/images/thumb/6/63/CDR_CallAnswer.jpg/640px-CDR_CallAnswer.jpg" alt=""><figcaption></figcaption></figure>

#### Case 2: Call Unanswered

<figure><img src="https://docs.telcobridges.com/w/images/thumb/5/5e/CDR_UnansweredCall.jpg/640px-CDR_UnansweredCall.jpg" alt=""><figcaption></figcaption></figure>

#### Case 3: Call Transferred

<figure><img src="https://docs.telcobridges.com/w/images/thumb/b/b0/CDR_CallTransferBleg.jpg/640px-CDR_CallTransferBleg.jpg" alt=""><figcaption></figcaption></figure>

<figure><img src="https://docs.telcobridges.com/w/images/thumb/b/b7/CDR_CallTransferCleg.jpg/640px-CDR_CallTransferCleg.jpg" alt=""><figcaption></figcaption></figure>

### Text-based Call Detail Records

[Text-based call detail records](https://prosbcdocs.telcobridges.com/configuration-details/configuration-by-web-portal-category/call-detail-records-cdr/cdr-variables)

### RADIUS Call Detail Records

[RADIUS](https://prosbcdocs.telcobridges.com/appendices/appendix-a-glossary/glossary-radius)

### Call Detail Records in High Availability (HA) Environment

The term HA refers to a system equipped with primary and secondary host controllers (i.e. A SBC deployed in a 1+1 configuration, a TMG7800 gateway with redundant controllers or Tmedia gateways deployed in a 1+1 configuration)

* Text CDR only Mode
  * The active gateway application is storing text-based CDR records on the active host (i.e. non-zero bytes of CDR log file)
  * Each CDR record will only be present either on the primary or on the secondary host
  * The user needs to merge the CDR records from both the primary and secondary hosts to get all the data
* RADIUS CDR only Mode
  * CDR records will be sent out to the RADIUS server(s) from the gateway application on the active host only
  * No CDR records are stored on the HA system
* Text and RADIUS CDR Mode
  * CDR records will be sent out to RADIUS server(s) from the gateway application on the active host
  * The active gateway application is also storing text-based CDR records on the active host (i.e. non-zero bytes of CDR log file)
  * Also, each text-based CDR record will only be present either on the primary or on the secondary host
  * The user needs to merge the CDR records from both the primary and secondary hosts to get all the data
* RADIUS CDR with text CDR fallback Mode
  * If the RADIUS server(s) is(are) in service
    * CDR records will be sent out to the RADIUS server(s) from the gateway application on the active host only
  * If the RADIUS server(s) is(are) out of service
    * The active gateway application is storing text-based CDR records on the active host (i.e. non-zero bytes of CDR log file)
    * Each CDR record will only be present either on the primary or on the secondary host
    * The user needs to merge the CDR records from both the primary and secondary hosts to get all the data

\
Click here for instructions on [Customer defined CDR records](https://docs.telcobridges.com/wiki/CDR:Customer_defined_CDR_Records)

### Links on Call Detail Records

* [Text CDR](https://prosbcdocs.telcobridges.com/configuration-details/configuration-by-web-portal-category/call-detail-records-cdr/cdr-variables)
* [Radius CDR](https://prosbcdocs.telcobridges.com/appendices/appendix-a-glossary/glossary-radius)
* [Wikipedia - Call Retail Record](http://en.wikipedia.org/wiki/Call_detail_record)