Pexip's "Bring your own carrier" — using Pexip to dial out to PSTN

Pexip's "Bring your own carrier" (BYOC) enables users to dial out from a Pexip-registered video endpoint to PSTN numbers such as landline phones, mobile phones and audio bridges. So organizations no longer need a separate telephone in conference rooms.

The customer selects and engages a telephony carrier, and provides implementation details to their partner who then creates the necessary configuration. When a call is placed the Pexip Service routes it out to the chosen carrier who then handles the call the rest of the way.

BYOC currently supports calling from video endpoints registered to the Pexip Service only (it does not currently support calling from Trusted devices or the Pexip apps.)

This guide helps you understand what's involved in setting up BYOC, and how to complete the configuration in the Partner Portal.

Implementing BYOC

BYOC is flexible, and gives the customer control over which carrier to engage and the call plans they want to have. Here’s an outline of the things a customer needs to do to get BYOC up and running.

Customer decisions

  • First, the customer decides which calls they want to make and which carrier they want to deliver the calls.
    • They can have more than one carrier if they want.
    • Pexip currently supports Twilio, Unifon (Norway only) and Voxbone but other carriers can be onboarded and tested on a case-by-case basis.
  • The customer manages the commercial relationship with the carrier directly, so they can agree the call plan, routing options, and toll charges for the call segment handled by the carrier. Some customers already have an existing carrier. In these cases, they can simply continue their set-up and enable BYOC on Pexip for this carrier.
  • If the customer wants to use a session border controller (SBC), some configurations of Oracle's Enterprise Session Border Controller (E-SBC) have been tested with BYOC. Other SBCs may also be suitable but would need to be configured and tested.
  • They obtain a BYOC license from their partner and this enables the feature for all their video endpoints.
    • ERC premium customers pay no additional cost.
    • Otherwise the cost is based on the number of video endpoints they have registered to the Pexip Service.
  • They provide implementation details to their partner, who completes the configuration in the Partner Portal:
    • Proxies define the carrier SIP addresses that allow Pexip to deliver the call to the carrier.
    • Routing rules are configured based on the customer's and carrier's requirements, and rules also determine what the user enters at the video endpoint when placing calls.

Supporting additional carriers and the customer's own Session Border Control

If the customer requests a different carrier or wants their own Session Border Control please contact your Pexip Solution Architect.

Configuring BYOC in the Partner Portal

This section describes how to understand the options available to the customer for organizing rules depending on how many caller-ids they have with a carrier and what they want their users to enter when placing calls.

Overview of the steps

Here are the steps required to configure BYOC in the Partner Portal.

  • Order a BYOC license. For help ordering licenses see Ordering a new license plan.
  • Complete BYOC configuration in the Partner Portal:

    • Configure a proxy for each carrier the customer wants to use.
    • Configure rules for different types of calls.

Configuring a proxy

To find the BYOC configuration screen, go to the company you want to configure and select the Interop tab.

First, you need to configure a separate proxy for each carrier to be used by the customer; they can have one or more carriers for BYOC. The proxy holds the information that the Pexip Service needs to route the call to the carrier and authenticate with the carrier. The customer provides you with this information as they work with their chosen carrier directly.

  • Proxy tag is a name used to identify a carrier. When creating a rule you select the proxy it belongs to.
  • Primary and Backup proxy addresses are the carrier SIP addresses where Pexip sends the calls.

    Please note you must enter either port 5061 (recommended) or 5060, as we currently support the standard SIP ports only.

  • SIP Username and Password: SIP authentication is optional, but strongly recommended.

Configuring a rule

Rules enable the Pexip Service to route calls to the correct carrier proxy. Rules also determine the prefix that the end user enters into their video endpoint as the dial string.

The number of rules needed depends on how the customer and the carrier want to organize things. If the customer engages one carrier to deliver all the calls they want to make, then only one rule is needed, however, the customer could have more than one rule.

For example, a customer can have a rule for each destination country where calls are made to, or a rule per caller-id. Having one rule per country means they can set the prefix to the International Direct Dial and Country Code so that the end user doesn’t have to enter those details in addition to the prefix when placing a call.

  • A Prefix must be unique within a company.
  • The Prefix determines which rule (and hence which proxy) is used by the Pexip Service to route the call. If the start of the dial string entered by the end user matches the Prefix, this rule will be used.
  • The Prefix must meet one of the following criteria:

    • consist of one or more digits, or

    • consist of the + character on its own, or

    • start with the + character followed by one or more digits.

  • The dial string entered by the end user must:

    • be 3 digits long (to support emergency numbers), or

    • be at least 7 digits long, or

    • start with the + character followed by at least 7 digits.

  • The Prefix is used in conjunction with the Strip prefix or not field to determine the resulting dial string that is sent to the carrier:

    • When Strip prefix or not is unchecked, the dial string entered by the user is sent to the carrier unchanged.

    • When Strip prefix or not is checked, the Pexip Service removes the Prefix before sending the rest of the dial string to the carrier.

    Different carriers have different requirements when it comes to the dial string they receive, so the carrier's requirements must be taken into account when deciding how to set the Prefix and Strip prefix or not fields.

  • If the customer has Microsoft Teams CVI or Google Meet interoperability, and has endpoints that register to the same domain as used for Teams / Google Meet, then they cannot use a digit as a dial prefix (note that directly registered endpoints can use just the numerical conference ID for this type of call). It must be the non-digit + character (otherwise it will lead to a dial plan clash and calls will fail). Note that if the customer has Cisco endpoints they can use a macro to transform what the user has dialed to include a prefix that matches what is configured in these rules.

  • Caller id is sent to the carrier in the ‘From’ header field and is shown as the incoming caller id number on the receiving phone. In most cases, here you enter the phone number purchased from the carrier using E.164 format. If you're unsure, the carrier can confirm. Note that the same ID is used for all calls from all endpoints using the same rule.
  • Proxy set is where you select the proxy/carrier to which this rule belongs.

Examples of different configurations and the resultant dial strings

Here are some examples showing different configurations of Prefix and Strip prefix or not, and consequently what the user must enter to place a call, and what the carrier receives. Note that all dial strings end with (where represents the domain the customer uses on the Pexip Service) to make a valid SIP address.

Prefix value Strip prefix or not Dial string entered by the user Carrier receives
+44 No
+ No