# Outbound Trunk Object

JSON:API object with type `voice_out_trunks`.

Authentication data is returned only inside `data.attributes.authentication_method`.

## Request

### URI Parameters

| Name | Type | Is Required? | Description |
| --- | --- | --- | --- |
| id | `string` | Yes | Unique identifier of the outbound trunk. |

### Data Attributes

| Name | Type | Description |
| --- | --- | --- |
| name | `string` | The outbound trunk name. |
| external\_reference\_id | `string` | Optional identifier for the outbound trunk in the customer's external system. Maximum length is 100 characters. |
| allowed\_rtp\_ips | Array of `strings` | Allowed RTP IP addresses for media traffic. |
| on\_cli\_mismatch\_action | `string` | The action applied when the CLI does not match the allowed DID list. Possible values:   `send_original_cli` - pass the original `From` header value from your system to the destination without modification.   `reject_call` - reject the call if the `From` header value does not match any DID allowed on the trunk.   `replace_cli` - replace the CLI with one of the DIDs allowed on the trunk. |
| capacity\_limit | `integer` | The capacity limit of the outbound trunk. |
| allow\_any\_did\_as\_cli | `boolean` | When set to `true`, any eligible DID can be used as CLI for the trunk. |
| status | `string` | The status of the outbound trunk. Possible values:   `active` - the trunk can be used for outbound traffic.   `blocked` - outbound traffic on the trunk is blocked. |
| threshold\_reached | `boolean` | Indicates whether the 24-hour threshold amount has been reached. |
| threshold\_amount | `string` | The 24-hour threshold limit. |
| default\_dst\_action | `string` | The default destination action. Possible values:   `allow_all` - allow calls to all destinations except the prefixes listed in `dst_prefixes`.   `reject_all` - reject calls to all destinations except the prefixes listed in `dst_prefixes`. |
| dst\_prefixes | Array of `strings` | The destination prefixes allowed or rejected based on `default_dst_action`. |
| emergency\_enable\_all | `boolean` | When set to `true`, all eligible DIDs of the account can be used for emergency calling on this trunk. |
| media\_encryption\_mode | `string` | Media encryption mode. Possible values:   `disabled` - media encryption is turned off.   `srtp_sdes` - use SRTP encryption with SDES key exchange.   `srtp_dtls` - use SRTP encryption with DTLS key exchange.   `zrtp` - use SRTP encryption with ZRTP key exchange. |
| callback\_url | `string` | The callback URI. Can be `null` or a valid HTTP(S) URL. |
| force\_symmetric\_rtp | `boolean` | Enables symmetric RTP / COMEDIA mode. |
| rtp\_ping | `boolean` | When enabled, DIDWW sends an empty RTP packet after call establishment. |
| rtp\_timeout | `integer` | Disconnects the call if RTP packets do not arrive within the specified time. Supported values are from 30 to 600 seconds. |
| created\_at | `date&time` | The date and time when the outbound trunk was created. |
| authentication\_method | `object` | Authentication method object. See [Authentication Method](#outbound-trunk-authentication-method-v34). |

### Authentication Method

The outbound trunk authentication is returned in the `authentication_method` attribute.

Supported authentication method types:

- `credentials_and_ip` - uses SIP credentials together with allowed IP addresses.
- `ip_only` - uses allowed IP addresses only.
- `twilio` - uses a Twilio Account SID for authentication.

### Authentication Method Attributes by Type

The following attributes are part of the `authentication_method` object:

credentials\_and\_ipip\_onlytwilio

| Name | Type | Description |
| --- | --- | --- |
| allowed\_sip\_ips | Array of `strings` | The allowed originating SIP IPs. |
| tech\_prefix | `string` | An optional technical prefix added before the destination number. The maximum length is 8 characters and only digits and `#` are supported. |
| username | `string` | The digest authentication username. |
| password | `string` | The digest authentication password. |

| Name | Type | Description |
| --- | --- | --- |
| allowed\_sip\_ips | Array of `strings` | The allowed originating SIP IPs. |
| tech\_prefix | `string` | An optional technical prefix added before the destination number. The maximum length is 8 characters and only digits and `#` are supported. |

| Name | Type | Description |
| --- | --- | --- |
| twilio\_account\_sid | `string` | The Twilio Account SID. It is a 34-character identifier of the Twilio account. |

### Object Relationships

| Name | Type | Description |
| --- | --- | --- |
| dids | to-many | [DID Object](../did/did-object.html#did-object-v34) |
| emergency\_dids | to-many | DIDs assigned for emergency calling on the outbound trunk. |

On this page