Firewall Configuration for WebRTC Calls (End-User Networks)
This article describes the required firewall configuration for end-users who want to make WebRTC voice calls from our web application.
TrueEngage uses Telnyx WebRTC for real-time audio communication.
If users are behind a corporate firewall, specific IP addresses, domains, ports, and protocols must be allowed for calls to work correctly.
⚠️ Important
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This configuration applies to end-user networks (customers, agents, employees).
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This is NOT a Genesys configuration.
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These rules are required on the user’s corporate firewall
Symptoms of Missing Firewall Rules
If required firewall rules are blocked, users may experience:
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Calls that connect but no audio in either direction
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Calls that never fully connect
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Calls that immediately drop
Required Firewall Rules
1. WebRTC Signaling (Call Setup)
Used to establish and control WebRTC calls.
|
Destination |
Port |
Protocol |
|---|---|---|
|
rtc.telnyx.com |
443 |
TCP (WSS) |
2. STUN & TURN Servers (NAT Traversal and Media Relay)
Required to allow audio to flow through NATs and restrictive firewalls.
|
Destination |
Port |
Protocol |
Purpose |
|---|---|---|---|
|
stun.telnyx.com |
3478 |
UDP |
STUN (NAT discovery) |
|
turn.telnyx.com |
3478 |
UDP / TCP |
TURN (media relay) |
|
stun.l.google.com |
19302 |
UDP |
Secondary STUN server |
ℹ️ The Telnyx WebRTC SDK uses multiple STUN servers (including Google STUN) to improve reliability.
3. Media (RTP Audio Streams)
Actual voice traffic is transmitted using RTP over UDP.
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Protocol: UDP
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Ports: 16384 to 32768
Allowed IP ranges:
36.255.198.128/25
50.114.136.128/25
50.114.144.0/21
64.16.226.0/24
64.16.227.0/24
64.16.228.0/24
64.16.229.0/24
64.16.230.0/24
64.16.248.0/24
64.16.249.0/24
103.115.244.128/25
185.246.41.128/25
❗ Blocking UDP media traffic will result in connected calls with no audio.
4. SIP Signaling (Used Internally by Telnyx)
Even though the application uses WebRTC, Telnyx uses SIP internally for call routing.
IP Address |
Port |
Protocol |
| 192.76.120.10 | 5060 / 5061 | UDP / TCP |
| 64.16.250.10 | 5060 / 5061 | UDP / TCP |
| 185.246.41.140 | 5060 / 5061 | UDP / TCP |
| 185.246.41.141 | 5060 / 5061 | UDP / TCP |
| 103.115.244.145 | 5060 / 5061 | UDP / TCP |
| 103.115.244.146 | 5060 / 5061 | UDP / TCP |
| 192.76.120.31 | 5060 / 5061 | UDP / TCP |
| 64.16.250.13 | 5060 / 5061 | UDP / TCP |
| 103.115.244.158 | 5060 / 5061 | UDP / TCP |
| 103.115.244.159 | 5060 / 5061 | UDP / TCP |
Important Notes for IT & Security Teams
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TURN over TCP 3478 is required for highly restricted environments
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SIP and media IP ranges are maintained by Telnyx and may change over time
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The authoritative, up-to-date SIP IP list is available at: https://sip.telnyx.com/
Need Help?
If calls still fail after applying these rules:
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Verify that UDP traffic is not blocked or rate-limited
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Confirm that outbound AND inbound rules are applied
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Contact your network administrator to confirm firewall logs
If needed, our support team can assist in validating the configuration.