# Authenticating with User Credentials File

The 2.0 version of NATS server introduced the idea of JWT-based authentication. Clients interact with this new scheme using a user JWT and the private key from an NKey pair. To help make connecting with a JWT easier, the client libraries support the concept of a credentials file. This file contains both the private key and the JWT and can be generated with the `nsc` tool. The contents will look like the following and should be protected because it contains a private key. This creds file is unused and only for example purposes.

```ascii
-----BEGIN NATS USER JWT-----
eyJ0eXAiOiJqd3QiLCJhbGciOiJlZDI1NTE5In0.eyJqdGkiOiJUVlNNTEtTWkJBN01VWDNYQUxNUVQzTjRISUw1UkZGQU9YNUtaUFhEU0oyWlAzNkVMNVJBIiwiaWF0IjoxNTU4MDQ1NTYyLCJpc3MiOiJBQlZTQk0zVTQ1REdZRVVFQ0tYUVM3QkVOSFdHN0tGUVVEUlRFSEFKQVNPUlBWV0JaNEhPSUtDSCIsIm5hbWUiOiJvbWVnYSIsInN1YiI6IlVEWEIyVk1MWFBBU0FKN1pEVEtZTlE3UU9DRldTR0I0Rk9NWVFRMjVIUVdTQUY3WlFKRUJTUVNXIiwidHlwZSI6InVzZXIiLCJuYXRzIjp7InB1YiI6e30sInN1YiI6e319fQ.6TQ2ilCDb6m2ZDiJuj_D_OePGXFyN3Ap2DEm3ipcU5AhrWrNvneJryWrpgi_yuVWKo1UoD5s8bxlmwypWVGFAA
------END NATS USER JWT------

************************* IMPORTANT *************************
NKEY Seed printed below can be used to sign and prove identity.
NKEYs are sensitive and should be treated as secrets.

-----BEGIN USER NKEY SEED-----
SUAOY5JZ2WJKVR4UO2KJ2P3SW6FZFNWEOIMAXF4WZEUNVQXXUOKGM55CYE
------END USER NKEY SEED------

*************************************************************
```

Given a creds file, a client can authenticate as a specific user belonging to a specific account:

!INCLUDE "../../_examples/connect_creds.html"