Getting Started with Telnyx

linkSignaling Addresses

Telnyx uses the same address for all SIP communications (inbound and outbound):

sip.telnyx.com

When using DNS A record resolution, sip.telnyx.com resolves to this IP address:

Primary: 192.76.120.10

When using SRV record resolution, sip.telnyx.com resolves to these IP addresses:

Primary: 192.76.120.10
Secondary: 64.16.250.10

If you use an ACL or Firewall on your network, make sure you whitelist these IP addresses.

linkMedia

The RTP port range used by Telnyx is 16384 to 65535 (UDP).

Telnyx uses the following media IP addresses to handle RTP streams. If you use an ACL or Firewall on your network, make sure you whitelist these IP addresses:

Subnet (containing all media IPs)

64.16.224.0/19

List of individual IPs

64.16.240.36
64.16.240.20
64.16.240.4
64.16.235.18
64.16.248.82
64.16.248.2
64.16.248.98
64.16.236.18
64.16.248.19 
64.16.248.35
64.16.249.3
64.16.249.19
64.16.248.50
64.16.248.114
64.16.248.66

The content of this list is updated regularly. Telnyx will send notifications if any changes are made.

linkCodecs

Telnyx supports the following codecs:

  • G.722
  • G.711U (PCMU)
  • G.711A (PCMA)
  • G.729
  • Opus (supported for IB and OB calls, for IB calls though it's only allowed when using TLS or TCP transport)
  • H.264

linkAdditional Network Information

Information on peering with Telnyx can be found on PeeringDB.

Points of presence

United StatesEquinix CH1, DC2, SV1
CanadaCologix VAN2
UKEquinix LD6

linkSetting Up Mission Control

Initial setup

  1. Log in to Telnyx Mission Control.
  2. Create a Connection for your SIP device. You can choose between the following types of authentication:
    • Credentials (username and password)
    • IP address
    • FQDN + Credentials

Making outbound calls

  1. Create an Outbound Profile and assign your Connection to it.
  2. When using UDP or TCP, configure your SIP device to send calls to sip:sip.telnyx.com:5060.
  3. When using TLS, configure your SIP device to send calls to sip:sip.telnyx.com:5061.
  4. When using the FQDN + Credentials authentication, only Credentials will be used.

Receiving inbound calls

  1. Purchase a number and assign it to your Connection.
  2. If you chose Credentials authentication, you need to register your SIP device with your username and password to sip:sip.telnyx.com:5060 before receiving calls.
  3. When using IP Authentication Telnyx will initiate a call from the IP address 192.76.120.10 to your Connection using UDP transport by default. If you prefer TCP or TLS transport you can edit the SIP Transport Protocol option for Inbound Calls in the Connections page.
  4. When using IP authentication, you can enter multiple IP addresses and set different priorities. Telnyx will attempt to connect calls to each IP address following the priorities order and the No Ringback Timeout setting. More advanced routing settings can be configured from the Numbers page under Routing options.
  5. When using FQDN + Credentials authentication, Telnyx will route calls to the resolved FQDN records .

linkEncryption

Telnyx supports TLS for encrypted signaling and SRTP/ZRTP for encrypted media.

For outbound calls, you can configure your device to use TLS and SRTP and make calls without further configuration on the Telnyx portal.

To use ZRTP, you need to enable this option under Encrypted Media for Outbound Calls in the Connections page.

For inbound calls, you can enable TLS and either SRTP or ZRTP in the Connections page.

linkAnchorSite™

Telnyx will regularly ping your Connection using either SIP OPTIONS messages or ICMP ping messages to calculate round trip timings from all Telnyx available sites.

The site with the lowest latency will be selected as the AnchorSite™, and the media for Inbound/Outbound calls will be anchored in that site.

If you prefer not to receive pings from Telnyx and manually anchor your media in one of the available sites, you can do so from the Connections page.

linkMedia Handling

By default, all Telnyx numbers are set to Default Media Handling Mode. This mode allows for transcoding and other advanced media handling options. Each number can be configured to use Proxy Media Handling Mode, which disables transcoding and all other advanced media handling options.

Telnyx will automatically detect your media IP address by monitoring the RTP packets received during the first seconds after media establishment on the media IP address:port pair and adjust it automatically if it differs from the pair announced by you during call establishment. This option can be disabled using the option Disable RTP Auto Adjust in the Numbers page under Expert Options.

The same behavior can be extended to the whole duration of the call by selecting the option Accept any RTP packets in the Numbers page under Expert Options.

linkFAX

Telnyx supports FAX calls using G.711 codec or T38.

For inbound FAX calls, Telnyx will expect the customer connection to send a T38 reinvite by default. If no reinvite is received, the call will continue with G.711 codec. This can be disabled using the T38 option in the Numbers page.

For outbound FAX calls you can chose different FAX modes using T.38 Re-invite Initiated By options in the Outbound tab on the Connections page:

  • Telnyx Telnyx will send a T38 reinvite after detecting FAX tone
  • Customer Telnyx will expect a T38 reinvite from the customer
  • Disabled Telnyx will not send a T38 reinvite and will reject an T38 reinvite sent from the customer

linkSTUN

Telnyx provides STUN service using the following addresses:

stun.telnyx.com

linkTURN

Telnyx provides TURN service using the following address:

turn.telnyx.com

Please request the TURN username and password by email to support@telnyx.com.

linkWebRTC (Beta)

Telnyx supports WebRTC calls through the following:

Unencrypted websocket:

ws://sip.telnyx.com:5066

Encrypted websocket with flexible TLS cipher suites for use with most browsers (i.e. Firefox):

wss://sip.telnyx.com:7443

Client configuration

Most WebRTC clients will ask for the following settings:

WebsocketUse one from the list above
UserSame as SIP username
PasswordSame as SIP password
Domain/Realmsip.telnyx.com
SIP URI/Proxysip:username@sip.telnyx.comsip:username
@sip.telnyx.com
Registrarsip:sip.telnyx.comsip:sip
.telnyx.com
STUN serverstun.telnyx.com
TURN serverturn.telnyx.com

linkContact Us

Don’t hesitate to reach out if you have any questions!