Source note · ITU-T Q.850 call clearing cause values
A Q.850 cause value is a class in bits 5 to 7 and a value within the class in bits 1 to 4, so the cause number is the class times 16 plus the value, and that arithmetic holds for all 70 cause values in Table 1.
field report · Checked 2026-09-15
The cause value is divided into two fields, a class (bits 5 to 7) and a value within the class (bits 1 to 4).
- Vendor
- ITU-T
- Product
- ITU-T Recommendation Q.850
- Subsystem
- Cause and location
- Deployment
- not restricted
- Region
- not restricted
- Release range
- edition 10/2018
- Status
- field report
- Checked
- 2026-09-15
Sources
- ITU-T Recommendation Q.850 (10/2018), Usage of cause and location in the Digital Subscriber Signalling System No. 1 and the Signalling System No. 7 ISDN user part — International Telecommunication Union (ITU-T) · tier 1 standards and regulators · clause 6.2.5 Cause value and Table 1
Cite this note
APA
WarmTransfer. (2026, September 15). ITU-T Q.850 call clearing cause values: source note q850-cause-number-is-class-times-sixteen-plus-value. WarmTransfer. https://warmtransfer.net/knowledge/claims/q850-cause-number-is-class-times-sixteen-plus-value
BibTeX
@misc{warmtransfer-claim-q850-cause-number-is-class-times-sixteen-plus-value,
title = {ITU-T Q.850 call clearing cause values: source note q850-cause-number-is-class-times-sixteen-plus-value},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/q850-cause-number-is-class-times-sixteen-plus-value},
note = {Source note q850-cause-number-is-class-times-sixteen-plus-value, checked 2026-09-15}
}