SIP Trunks API

The SIP Trunks API lets organization admins manage BYO SIP trunk gateways for outbound and inbound telephony through Burki’s SIP bridge. All SIP trunk management endpoints require an authenticated organization admin.

Base path: /api/v1/sip-trunks

SIP trunk records include carrier credentials. Treat responses and request bodies as sensitive and avoid logging full payloads.

SIP Trunk Object

{
  "id": "7f502da1-0f06-4e52-9262-4e625c53791a",
  "name": "Primary Carrier",
  "gateway": "sip.example-carrier.com",
  "username": "sip-user",
  "password": "sip-password",
  "priority": 1,
  "enabled": true,
  "register": true,
  "provider": "example-carrier"
}

Field	Type	Description
`id`	string	Server-generated trunk UUID
`name`	string	Unique trunk name within the organization
`gateway`	string	SIP gateway hostname or IP
`username`	string	SIP auth username
`password`	string	SIP auth password
`priority`	integer	Lower values are preferred first
`enabled`	boolean	Whether the trunk is eligible for routing
`register`	boolean	Whether FreeSWITCH should register to the gateway
`provider`	string	Optional provider label

PBX Allowlist and Registration

For the current hosted SIP bridge, customer PBX/carrier firewalls should allow:

Burki SIP bridge IP: 52.21.157.171
SIP signaling: UDP/TCP 5060
SIP TLS: TCP 5061, if enabled
RTP media: UDP 10000-20000

Use gateway for the customer’s PBX/carrier host and port. If Burki should register to the PBX, set register: true and provide the PBX username/password. If the PBX uses IP authentication instead, set register: false and allowlist 52.21.157.171 as the trusted SIP peer.

Registration example

{
  "name": "FreePBX primary",
  "gateway": "138.197.131.209:6061",
  "username": "9228",
  "password": "sip-password",
  "priority": 1,
  "enabled": true,
  "register": true,
  "provider": "freepbx"
}

For inbound calls, configure the PBX/carrier to send INVITEs to 52.21.157.171:5060 and allow RTP from 52.21.157.171 on UDP 10000-20000. For outbound calls, the PBX/carrier must accept INVITEs and RTP from 52.21.157.171. If multiple DIDs share one PBX extension, the PBX must also include the original called DID in Diversion, History-Info, X-Original-Called, P-Called-Party-ID, the Request-URI, or the To user so Burki can route to the correct assistant.

List Trunks

GET /api/v1/sip-trunks
Authorization: Bearer YOUR_TOKEN

Returns trunks sorted by priority.

Response

[
  {
    "id": "7f502da1-0f06-4e52-9262-4e625c53791a",
    "name": "Primary Carrier",
    "gateway": "sip.example-carrier.com",
    "username": "sip-user",
    "password": "sip-password",
    "priority": 1,
    "enabled": true,
    "register": true,
    "provider": "example-carrier"
  }
]

Create Trunk

POST /api/v1/sip-trunks
Authorization: Bearer YOUR_TOKEN
Content-Type: application/json

Request

{
  "name": "Primary Carrier",
  "gateway": "sip.example-carrier.com",
  "username": "sip-user",
  "password": "sip-password",
  "priority": 1,
  "enabled": true,
  "register": true,
  "provider": "example-carrier"
}

Returns 201 Created with the created SIP trunk object. Duplicate names return 400 Bad Request.

Get Trunk

GET /api/v1/sip-trunks/{trunk_id}
Authorization: Bearer YOUR_TOKEN

Returns one SIP trunk object or 404 Not Found.

Update Trunk

PUT /api/v1/sip-trunks/{trunk_id}
Authorization: Bearer YOUR_TOKEN
Content-Type: application/json

All fields are optional. Empty fields are ignored only if omitted; send the exact value you want persisted.

Request

{
  "name": "Primary Carrier",
  "gateway": "sip2.example-carrier.com",
  "priority": 2,
  "enabled": true
}

Returns the updated trunk.

Delete Trunk

DELETE /api/v1/sip-trunks/{trunk_id}
Authorization: Bearer YOUR_TOKEN

Returns 204 No Content on success.

Enable or Disable Trunk

POST /api/v1/sip-trunks/{trunk_id}/enable
Authorization: Bearer YOUR_TOKEN

POST /api/v1/sip-trunks/{trunk_id}/disable
Authorization: Bearer YOUR_TOKEN

Returns the updated trunk object.

Sync to SIP Bridge

POST /api/v1/sip-trunks/sync
Authorization: Bearer YOUR_TOKEN

Pushes enabled trunk configuration to the SIP bridge. The API returns success if Burki updates its org config and starts bridge sync; bridge sync failures are logged server-side and should be checked in operations logs.

Response

{
  "success": true,
  "message": "Synced 2 enabled trunk(s) to bridge",
  "total_trunks": 3,
  "enabled_trunks": 2
}

Assign a Phone Number to a SIP Trunk

Phone-number routing uses the organization phone-number update endpoint:

PATCH /api/v1/assistants/organization/phone-numbers/{phone_number_id}
Authorization: Bearer YOUR_TOKEN
Content-Type: application/json

Request

{
  "sip_trunk_id": "7f502da1-0f06-4e52-9262-4e625c53791a"
}

Send an empty string to clear the SIP trunk assignment:

{
  "sip_trunk_id": ""
}

Error Responses

Status	Cause
`400`	Duplicate trunk name or invalid update
`403`	Authenticated user is not an organization admin
`404`	Organization or trunk not found
`500`	Unexpected server error

API Documentation

Assistants

Assistant Phone Numbers

Assistant Documents (RAG)

Voice Cloning

Calls

Messaging

SIP Trunks

Billing

Phone Number Management

Call Data

Organization

Webhooks & System

Campaigns

WebSockets

Tools & Custom Actions

Conversation Flows

Learning & Memory

SIP Trunk Object

PBX Allowlist and Registration

List Trunks

Create Trunk

Get Trunk

Update Trunk

Delete Trunk

Enable or Disable Trunk

Sync to SIP Bridge

Assign a Phone Number to a SIP Trunk

Error Responses

​SIP Trunk Object

​PBX Allowlist and Registration

​List Trunks

​Create Trunk

​Get Trunk

​Update Trunk

​Delete Trunk

​Enable or Disable Trunk

​Sync to SIP Bridge

​Assign a Phone Number to a SIP Trunk

​Error Responses

SIP Trunk Object

PBX Allowlist and Registration

List Trunks

Create Trunk

Get Trunk

Update Trunk

Delete Trunk

Enable or Disable Trunk

Sync to SIP Bridge

Assign a Phone Number to a SIP Trunk

Error Responses