Guest

Preview Tool

Cisco Bug: CSCsy82117 - CUBE: SIP to H323 doesn't complete T.38 negotiation w/o inbound OLC

Last Modified

Mar 06, 2018

Products (1)

  • Cisco IOS

Known Affected Releases

12.4(24)T 12.4(24.6)T4

Description (partial)

Symptom:
CUBE fails to send an OLC to initiate T.38 when operating in a SIP --> H323 call flow. Specifically, on an inbound SIP call, the H.323 will start T.38 negotiation. A H245 requestMode will be received and CUBE will respond with requestModeAck. The logical channels will be closed in both directions with CloseLogicalChannel and CloseLogicalChannelAck messages. However, CUBE will not originate an OLC for T.38 operation until the far end H.323 sends one first.

Conditions:
This was seen specifically in this call flow:
Fax-A---SIP---PSTN---SIP---CUBE---H323---CUCM---SIP---ATA---Fax-B

Call is from Fax-A to Fax-B.
Bug details contain sensitive information and therefore require a Cisco.com account to be viewed.

Bug Details Include

  • Full Description (including symptoms, conditions and workarounds)
  • Status
  • Severity
  • Known Fixed Releases
  • Related Community Discussions
  • Number of Related Support Cases
Bug information is viewable for customers and partners who have a service contract. Registered users can view up to 200 bugs per month without a service contract.