diff --git a/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/FormLoginLdapFactory.php b/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/FormLoginLdapFactory.php
index 026a3d65ac6ba..2932f2c1025e7 100644
--- a/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/FormLoginLdapFactory.php
+++ b/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/FormLoginLdapFactory.php
@@ -45,7 +45,7 @@ public function addConfiguration(NodeDefinition $node)
 
         $node
             ->children()
-                ->scalarNode('service')->end()
+                ->scalarNode('service')->defaultValue('ldap')->end()
                 ->scalarNode('dn_string')->defaultValue('{username}')->end()
             ->end()
         ;
diff --git a/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/HttpBasicLdapFactory.php b/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/HttpBasicLdapFactory.php
index f2b1695c83772..2b7e6201dfa44 100644
--- a/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/HttpBasicLdapFactory.php
+++ b/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/HttpBasicLdapFactory.php
@@ -55,7 +55,7 @@ public function addConfiguration(NodeDefinition $node)
 
         $node
             ->children()
-                ->scalarNode('service')->end()
+                ->scalarNode('service')->defaultValue('ldap')->end()
                 ->scalarNode('dn_string')->defaultValue('{username}')->end()
             ->end()
         ;
diff --git a/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/UserProvider/LdapFactory.php b/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/UserProvider/LdapFactory.php
index 8aea9074bd71a..2612bf522149c 100644
--- a/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/UserProvider/LdapFactory.php
+++ b/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/UserProvider/LdapFactory.php
@@ -47,7 +47,7 @@ public function addConfiguration(NodeDefinition $node)
     {
         $node
             ->children()
-                ->scalarNode('service')->isRequired()->cannotBeEmpty()->end()
+                ->scalarNode('service')->isRequired()->cannotBeEmpty()->defaultValue('ldap')->end()
                 ->scalarNode('base_dn')->isRequired()->cannotBeEmpty()->end()
                 ->scalarNode('search_dn')->end()
                 ->scalarNode('search_password')->end()
diff --git a/src/Symfony/Component/Ldap/README.md b/src/Symfony/Component/Ldap/README.md
index 3bcb8452783a5..9dbd2b935d132 100644
--- a/src/Symfony/Component/Ldap/README.md
+++ b/src/Symfony/Component/Ldap/README.md
@@ -11,14 +11,10 @@ have been marked as internal as they still needed some work.
 Breaking changes were introduced in Symfony 3.1, so code relying on
 previous version of the component will break with this version.
 
-Documentation
--------------
-
-The documentation for the component can be found [online] [0].
-
 Resources
 ---------
 
+  * [Documentation](https://symfony.com/doc/current/components/filesystem/index.html)
   * [Contributing](https://symfony.com/doc/current/contributing/index.html)
   * [Report issues](https://github.com/symfony/symfony/issues) and
     [send Pull Requests](https://github.com/symfony/symfony/pulls)