### API Versioning Example (Register Service)

Source: https://devportal.ing.pl/#/services/index_/services

An example URL for the 'register' service, demonstrating the versioning scheme `v2_1.1`.

```APIDOC
## API Versioning Example

### Description
This example shows the URL structure for the 'register' service, including the API version `v2_1.1`.

### Endpoint
`https://api.ing.pl/gateway/api/v2_1.1/auth/v2_1.1/register`
```

--------------------------------

### Public Key for Signature Verification

Source: https://devportal.ing.pl/#/services/index_/services

The public key for verifying the Bank's signature is available at the provided URL.

```APIDOC
## Public Key for Signature Verification

### Description
Access the public key required to verify the Bank's signature at the following URL.

### Endpoint
`https://www.ing.pl/psd2cert/6340135475_pieczec.pem`
```

--------------------------------

### Production API Domain

Source: https://devportal.ing.pl/#/services/index_/services

The production API is accessible via the following domain. This is the base URL for all API requests.

```APIDOC
## Production API Domain

### Description
The production API is accessible under the domain `api.ing.pl/gateway`. Use this as the base URL for all your API requests.

### Endpoint
`https://api.ing.pl/gateway`
```

--------------------------------

### QWAC Certificate Verification

Source: https://devportal.ing.pl/#/services/index_/services

Information for verifying QWAC certificates can be found on the European Commission's Trust List browser.

```APIDOC
## QWAC Certificate Verification

### Description
QWAC certificates are verified based on information available on the European Commission's Trust List browser.

### External Resource
[https://webgate.ec.europa.eu/tl-browser](https://webgate.ec.europa.eu/tl-browser)
```

--------------------------------

### Service Availability and Maintenance

Source: https://devportal.ing.pl/#/services/index_/services

Information regarding production API unavailability and planned maintenance is published on a dedicated support page. General bank service maintenance notices are in the 'News' section.

```APIDOC
## Service Availability and Maintenance

### Description
Information about production API downtime and scheduled maintenance is posted on the ING support page. Broader bank service maintenance updates are in the 'News' section of the main ING website.

### Support Information
[https://www.ing.pl/psd2supportinfo](https://www.ing.pl/psd2supportinfo)

### General News
[https://www.ing.pl/](https://www.ing.pl/) (News section)
```

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