> ## Documentation Index
> Fetch the complete documentation index at: https://docs.ebury.com/llms.txt
> Use this file to discover all available pages before exploring further.

# End user

It is what we classically describe as a contact for machine-2-machine communication.It is the most common mechanism that customers choose.

## Step 1

With an user’s credentials, begin with **[login](https://postman.ebury.io/#ca4d9cc0-410f-4ffd-9773-cb0c968309af)**.

The YoPass link of the Welcome email will contain the following variables necessary for the API call.

1. `email`
2. `auth_client_id`
3. `password` (if you have updated it when you logged into EBO, please use the current password)

A successful API response will contain the code, which should be used in the next API call.

```sh theme={null}
curl --location -g '{{AUTH_URL}}/login' \
    -header 'Content-Type: application/x-www-form-urlencoded' \
    --data-urlencode 'email={{email}}' \
    --data-urlencode 'password={{password}}' \
    --data-urlencode 'client_id={{auth_client_id}}' \
    --data-urlencode 'state=state'
```

## Step 2

Next, **[complete Strong Customer Authentication](https://postman.ebury.io/#f167ab53-2790-42b3-9560-ad96decf6794)** (either with the code in the Authenticator App or an SMS)

1. The following parameters should be gathered from the YoPass link of the Welcome email.

   1. `redirect_uri`
   2. `auth_client_id`
   3. The parameter, `Authorization` in the header should be built by appending the `auth_client_secret` to `auth_client_id` using colon (:) as the delimiter between the two parameters.

2. The the value for code should be gathered from the response of the previous API call.

```sh theme={null}
curl --location -g '{{AUTH_URL}}/token' \
    --header 'Authorization: Basic {{credentials}}' \
    --header 'Content-Type: application/x-www-form-urlencoded' \
    --data-urlencode 'grant_type=authorization_code' \
    --data-urlencode 'code={{code}}' \
    --data-urlencode 'redirect_uri={{redirect_uri}}' \
    --data-urlencode ‘client_id={{auth_client_id}}’
```

## Step 3

Next, **[get the access token](https://postman.ebury.io/#f488d2fb-d729-4bc5-85fd-f434d676bc87)**

1. The YoPass link of the Welcome email will contain the following variables necessary for the API call.

   1. `redirect_uri`
   2. The parameter, `Authorization` in the header should be built by appending the `auth_client_secret` to `auth_client_id` using colon (:) as the delimiter between the two parameters.

2. The value for code should be gathered from the response of the previous API call.

```sh theme={null}
curl --location -g '{{AUTH_URL}}/token' \
--header 'Authorization: Basic {{credentials}}' \
--header 'Content-Type: application/x-www-form-urlencoded' \
--data-urlencode 'grant_type=authorization_code' \
--data-urlencode 'code={{code}}' \
--data-urlencode 'redirect_uri={{redirect_uri}}'
```