Source note · SS7 and carrier interworking concepts
When overlap is carried into SIP under RFC 3578, each arriving SAM refreshes timer T10 and triggers a new INVITE with the accumulated digits, and 4xx-6xx responses do not trigger an ISUP REL until T10 expires with no more SAMs.
Checked 2026-09-24
- Vendor
- IETF
- Product
- SIP-ISUP gateways
- Subsystem
- overlap signalling
- Deployment
- carrier
- Region
- not restricted
- Release range
- current as of 2026-09-24
- Checked
- 2026-09-24
Sources
- RFC 3578: Mapping of Integrated Services Digital Network (ISDN) User Part (ISUP) Overlap Signalling to the Session Initiation Protocol (SIP) — RFC Editor / IETF · tier 1 standards and regulators · Section 3.2
Cite this note
APA
WarmTransfer. (2026, September 24). SS7 and carrier interworking concepts: source note ss7-carrier-interworking-overlap-new-invite. WarmTransfer. https://warmtransfer.net/knowledge/claims/ss7-carrier-interworking-overlap-new-invite
BibTeX
@misc{warmtransfer-claim-ss7-carrier-interworking-overlap-new-invite,
title = {SS7 and carrier interworking concepts: source note ss7-carrier-interworking-overlap-new-invite},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/ss7-carrier-interworking-overlap-new-invite},
note = {Source note ss7-carrier-interworking-overlap-new-invite, checked 2026-09-24}
}