Add k2k identity backend
diff --git a/README.rst b/README.rst
index 59f8a88..3fde09f 100644
--- a/README.rst
+++ b/README.rst
@@ -330,6 +330,25 @@
- wsgi
- shib2
+Use a custom identity driver with custom options
+
+.. code-block:: yaml
+
+ keystone:
+ server:
+ backend: k2k
+ k2k:
+ auth_url: 'https://keystone.example.com/v2.0'
+ read_user: 'example_user'
+ read_pass: 'password'
+ read_tenant_id: 'admin'
+ identity_driver: 'sql'
+ id_prefix: 'k2k:'
+ domain: 'default'
+ caching: true
+ cache_time: 600
+
+
Keystone client
---------------