SIP Reliable Provisional Response on CUBE and CUCM Configuration Example

Publisher

Cisco Systems

URL

https://www.cisco.com/c/en/us/support/docs/voice/session-initiation-protocol-sip/116086-configure-cube-cucm-sip-00.html

Published

2013-05-16

Updated

unknown

Accessed

2026-09-25

HTTP status

200

License

Cisco copyright; all rights reserved; no-redistribution; short excerpts and locators only

Source notes citing this source

• CUBE requires 100rel with rel1xx require 100rel under voice service voip > sip globally, or voice-class sip rel1xx require 100rel on a dial peer, and the dial-peer setting takes precedence. in context
• As documented in 2013, CUCM supported reliable provisional responses only as a UAC sending PRACK and could not itself send 180/183 with Require: 100rel as a UAS. in context
• When CUCM places a call with a Delayed Offer, the caller may not hear PSTN-generated ringback or announcements because no media path is established before the call is answered. in context
• Cisco documents SIP reliable provisional responses (PRACK/100rel) as a way to establish early media on delayed-offer calls without using extra media resources such as MTPs. in context
• In Unified CM the SIP Profile (Device > Device Settings > SIP Profile) has a SIP Rel1XX Options setting that can be set to send PRACK for 1xx messages. in context

Cite this source record

APA

WarmTransfer. (2013, May 16). SIP Reliable Provisional Response on CUBE and CUCM Configuration Example. WarmTransfer. https://warmtransfer.net/knowledge/sources/cisco-technote-116086-sip-rel1xx-cube-cucm

BibTeX

@misc{warmtransfer-cisco-technote-116086-sip-rel1xx-cube-cucm,
  title  = {SIP Reliable Provisional Response on CUBE and CUCM Configuration Example},
  author = {{WarmTransfer}},
  year   = {2013},
  url    = {https://warmtransfer.net/knowledge/sources/cisco-technote-116086-sip-rel1xx-cube-cucm},
  note   = {Cisco Systems, accessed 2026-09-25}
}