Getting Started with Telnyx High-Volume/Short-Duration

linkIntroduction

The Telnyx High-Volume/Short-Duration (HVSD) Voice product differs from the Full Featured Voice Product in the following aspects:

  • It supports a much higher volume of calls
  • It can only be used for Outbound calls
  • It supports fewer features
  • It’s available on a different domain: siphv.telnyx.com
  • It supports up to 200 CPS (call-setups per second) per IP address

linkUnsupported Features

The following features are not supported by Telnyx HVSD:

  • Emergency Calls (911)
  • TCP and TLS connections (only UDP supported)
  • G722, OPUS and H.264 codecs (only PCMU, PCMA and G.729 supported)
  • Credential authentication (only IP address supported)
  • SIP registrations
  • Call Control™
  • Anchorsite™ (media will be anchored in one of Telnyx US based servers)
  • WebRTC
  • None of the following media features:
    • Transcoding
    • T38 Fax Gateway
    • SIP INFO DTMF
    • Enable Comfort Noise for Call on Hold
    • RTCP reports
    • Encrypted Media Settings
    • Generate Ringback Tone
    • Instant Ringback

If any of these features are required please use the Telnyx Full Featured product at https://sip.telnyx.com/.

linkSignaling Addresses

Telnyx uses the same address for all SIP HVSD communications:

siphv.telnyx.com

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

Primary: 192.76.120.50

When using SRV record resolution, siphv.telnyx.com also resolves to this IP address:

Primary: 192.76.120.50

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

linkMedia

Most of the media features that are available on the Full Featured telephony product are not supported by the High-Volume/Short-Duration telephony product.

In addition to this, you will notice that the media IP addresses for HVSD calls are not part of the Telnyx IP space, so we suggest you disable you ACL/firewall for RTP media streams.

linkCodecs

Telnyx supports the following codecs for HVSD calls:

  • G.711U (PCMU)
  • G.711A (PCMA)
  • G.729

linkSetting Up Mission Control

Initial setup

  1. Log in to Telnyx Mission Control.
  2. Create a Connection for your SIP device. For HVSD you can only use the “IP address” type. If you require credential authentication please use the Telnyx Full Featured product at https://sip.telnyx.com/.

Making outbound calls

  1. Create an Outbound Profile and assign your Connection to it.
  2. Configure your SIP device to send calls to sip:sip.telnyx.com:5060 using UDP transport protocol.

Receiving inbound calls

Inbound calls are not supported by Telnyx HVSD.

If this is required please use the Telnyx Full Featured product at https://sip.telnyx.com/.

linkEncryption

Encryption is not supported by Telnyx HVSD.

If this is required please use the Telnyx Full Featured product at https://sip.telnyx.com/.

linkAnchorSite™

AnchorSite™ is not supported by Telnyx HVSD.

If this is required please use the Telnyx Full Featured product at https://sip.telnyx.com/.

linkFAX

For HVSD calls Telnyx supports FAX calls using G.711 codec only, T38 is not supported.

If this is required please use the Telnyx Full Featured product at https://sip.telnyx.com/.

linkSTUN

Telnyx provides STUN service using the following addresses:

stun.telnyx.com:3478

linkTURN

Telnyx provides TURN service using the following address:

turn.telnyx.com:3478

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

linkContact Us

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