Source note · Echo on VoIP calls
Cisco explains that the packet segment of a VoIP call adds significant delay, typically 30 ms in each direction, which makes echoes from analog tail circuits perceptible when they were previously indistinguishable from sidetone.
Checked 2026-09-25
The introduction of delay causes echoes (from analog tail circuits), that were normally indistinguishable from the side tone, to be now perceived by the user.
- Vendor
- Cisco
- Product
- Cisco IOS voice gateways
- Subsystem
- delay-thresholds
- Deployment
- on-premises
- Region
- not restricted
- Release range
- as documented 2008-04-02
- Checked
- 2026-09-25
Sources
- Troubleshooting Echo Problems between IP Phones and IOS Gateways — Cisco · tier 2 current vendor documentation · IP Phone User Hears Echo section
Cite this note
APA
WarmTransfer. (2026, September 25). Echo on VoIP calls: source note echo-on-calls-packet-delay-exposes-echo. WarmTransfer. https://warmtransfer.net/knowledge/claims/echo-on-calls-packet-delay-exposes-echo
BibTeX
@misc{warmtransfer-claim-echo-on-calls-packet-delay-exposes-echo,
title = {Echo on VoIP calls: source note echo-on-calls-packet-delay-exposes-echo},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/echo-on-calls-packet-delay-exposes-echo},
note = {Source note echo-on-calls-packet-delay-exposes-echo, checked 2026-09-25}
}