Call Detail Records (CDR)

The SBC can be configured to send Accounting CDR packets to a RADIUS server [3]. This data can be trended for monitoring purposes as well as traditional billing uses. For example, determining call completion rates at various high and low points during the day. This approach requires the implementation of a RADIUS server with the release specific Oracle Radius Dictionary (available in Downloads on the support portal), and a database backend / reporting mechanism.

If RADIUS is not the desired approach, the SBC store CDRs locally and then push them to a FTP/SFTP server on a scheduled basis [3]. Since that may require more local storage, an optional Storage Expansion Module can be used to extend the storage of CDRs locally on the SBC [3].

The following is a list of useful RADIUS attributes for characterizing and troubleshooting the VoIP network:

• Acct-Session-Time (46) - Call Duration: useful for detecting abnormally short or long call hold times
• Acct-Terminate-Cause (49) & Acme-Disconnect-Cause (62)
  • Call Disconnect Cause Code: useful for detecting abnormal call failures
  • See [3] for list of causes
• RTCP & RTP QoS Statistics -The SBC can incorporate call quality measurements (QoS) in CDR and for up to two RTP/RTCP bidirectional media flows per SIP session. Each bidirectional flow is referred to as a flow-set (FS1 and FS2). QoS collection requires an NIU with QoS capabilities and a QoS measurement setting to be enabled in configuration.
  • Acme-Called-RTCP-Packets-Lost_FS1 / FS2 (46 / 104) - integer, total for call
  • Acme-Called-RTCP-Avg-Jitter_FS1 / FS2 (47 / 105) - measured in ms
  • Acme-Called-RTCP-Avg-Latency_FS1 / FS2 (48 / 106) - measured in ms
  • Acme-Called-RTCP-MaxJitter_FS1 / FS2 (49 / 107) - measured in ms
  • Acme-Called-RTCP-MaxLatency_FS1 / FS2 (50 / 108) - measured in ms
  • Acme-Called-RTP-Packets-Lost_FS1 / FS2 (51 / 109) - integer, total for call
  • Acme-Called-RTP-Avg-Jitter_FS1 / FS2 (52 / 110) - measured in ms
  • Acme-Called-RTP-MaxJitter_FS1 / FS2 (53 / 111) - measured in ms
• Acme-Post-Dial-Delay (58) - Call Setup time in ms: Detect abnormal delays between SIP INVITE and 180 Ringing
• Acme-Session-Disposition (60)
  • Status of call attempt from SIP INVITE to answered or unanswered
  • 0 = unknown, 1 = call attempt, 2 = ringing, 3 = answered
• Acme-Disconnect-Initiator (61)
  • Party that disconnects the call
  • 0 = unknown, 1 = calling party, 2 = called party, 3 = internal