# Important information and recommendations

## User identifier

**⚠** It should be unique per user - the user ID cannot be recycled from one user to another.\
\
\&#xNAN;**⚠** It should be max 255 characters.\
\
\&#xNAN;**⚠** If you don’t respect these guidelines, iAdvize will consider all visitors as one and the same visitor. We will then associate all the conversations of visitors with the same user ID. This creates a confidentiality issue: visitors will then have access to the content of each-other's conversations, including text and attachments.

## Token encryption

When you generate a JWE which contains your user identifier, your library to generate this token should support A256GCM and RSA\_OAEP\_256 for creating the JWE. The inner JWS must be signed with RS256.

## Private Key storage

We store our private key using an external security tool call Vault, so our private key is not exposed through our code or any database access.

## About the external id usage (extId)

The visitor authentication system fully replaces the usage of the "ExtID". Then, if you use the visitor authentication system in an authenticated space of your website, you have to ensure that you are not using the "ExtID" system in parallel.

## Sending visitor data in the JWT token

In addition to the **userId** claim, an optional **visitorData** claim can be added to the JWT. This is how it would look like, before encryption:

<table data-header-hidden><thead><tr><th></th><th></th></tr></thead><tbody><tr><td><strong>Encoded</strong></td><td><strong>Decoded</strong></td></tr><tr><td><pre><code>eyJhbGciOiJSUzI1NiJ9.eyJodHRwczpcL1wvaWFkdml6ZS5jb21cL
3VzZXJJZCI6InRlc3RfZG9jdW1lbnRhdGlvbiIsImh0dHBzOlwvXC9
pYWR2aXplLmNvbVwvdmlzaXRvckRhdGEiOnsiY291bnRyeSI6IkZyY
W5jZSIsImZpcnN0TmFtZSI6IkphbmUiLCJsYXN0TmFtZSI6IkRvZSI
sInppcENvZGUiOiI0NDAwMCIsImFkZHJlc3MiOiI5IHJ1ZSBOaW5hI
FNpbW9uZSIsInBob25lTnVtYmVyIjoiKzMzNjUxMjI5ODU2IiwiY2l
0eSI6Ik5hbnRlcyIsImVtYWlsIjoiamFuZS5kb2VAZW1haWwuY29tI
n0sImlzcyI6Imh0dHBzOlwvXC90ZXN0LmlhZHZpemUuY29tIiwiZXh
wIjoxNjkxNTg4NzA3fQ.YrR0AisAbXzdcF7IGdKb4DGR0JOudaBS5E
s78YW_K3x65WfGlQhktYlgKud0AH8AgVi7EDb7aAWy5-9kuwezuqnL
CBBsaUBWJSkSN2OxVh0tSylNEKPIOYRlEG2lS6Fwlo_UdFkKQ1SIBG
jSEcPqepVwO58od6GlY5yjcTlOF6dj7RyON4KRxRir0wP6yCbZi2oa
4IS_beilJvS9ymZO-8zRnGHKS-J_xqqhpTkz8lF11Wb0UQz1ML16nq
uTIHLTzYO4e5UqdK0BUCIe0ivla6r5YQR5HYYhCKssvycqFdYh4mWF
lSziFkB-HKxbWCz-qbugkxvMicTXvEzwO-fELg
</code></pre></td><td><pre><code>{
"https://iadvize.com/userId": "test_documentation",
"iss": "https://test.iadvize.com",
"https://iadvize.com/visitorData": {
"country": "France",
"firstName": "Jane",
"lastName": "Doe",
"zipCode": "44000",
"address": "9 rue Nina Simone",
"phoneNumber": "+33651229856",
"city": "Nantes",
"email": "jane.doe@email.com"
},
"exp": 1690376935
}
</code></pre></td></tr><tr><td><p><strong>Detail</strong> <a href="https://jwt.io/#debugger-io?token=eyJhbGciOiJSUzI1NiJ9.eyJodHRwczpcL1wvaWFkdml6ZS5jb21cL3VzZXJJZCI6InRlc3RfZG9jdW1lbnRhdGlvbiIsImlzcyI6Imh0dHBzOlwvXC90ZXN0LmlhZHZpemUuY29tIiwiaHR0cHM6XC9cL2lhZHZpemUuY29tXC9jdXN0b21EYXRhIjp7ImNvdW50cnkiOiJGcmFuY2UiLCJmaXJzdE5hbWUiOiJKYW5lIiwibGFzdE5hbWUiOiJEb2UiLCJ6aXBDb2RlIjoiNDQwMDAiLCJhZGRyZXNzIjoiOSBydWUgTmluYSBTaW1vbmUiLCJwaG9uZU51bWJlciI6IiszMzY1MTIyOTg1NiIsImNpdHkiOiJOYW50ZXMiLCJlbWFpbCI6ImphbmUuZG9lQGVtYWlsLmNvbSJ9LCJleHAiOjE2OTAzNzY5MzV9.OVBa9CLEd8D6YZMGA_bU5UQASZDoH_3uGU9rtyeTR2D9e8jpDq-kWXbCQkwg-jCii6TterJMcF5jf-3VKn-tOMNrDXcIBz048gF4QDvIV8GeB5yKrXAprKlz1KbDyYiGIUgzZODCk1lUwkRYaHhMifOeq9dlFrw8QsGfAfgKxdpmtO9w9hYDF6ag616j2VGReRw9yhne5H-ouWHMWGCxo1JI4ZLMGD7gNoW4v4YvDfrInkh--HYIvDisdgeDXE0uiMUoh6MK8JlnVUva_Ra84ojFq_2Zto2k9J-bBEG-251zqWMlDdKPJky4G1GGLknvV8kags9QdEPNQ3wXqDI0gQ">here</a></p><p><br></p></td><td></td></tr></tbody></table>

It may contain the following fields, all optional strings:

```
address
city
country
email
firstName
lastName
phoneNumber
zipCode
```


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