anchor.diff:  
   IMPORTANT: Be sure to define an index on the `username` property, as this will be used for lookups.  If supported by the `Graph`, consider specifying a unique constraint as well.
   
  -A quick way to get started with the `SimpleAuthenticator` is to use TinkerGraph for the "credentials graph".  Recall that TinkerGraph is an in-memory graph and therefore always starts as "empty" when opened by `GraphFactory`.  To allow TinkerGraph to be used in this "getting started" capacity, Gremlin Server allows for a TinkerGraph-only configuration option called `credentialsDbLocation`.
  +Quick Start
  ++++++++++++
  +
  +A quick way to get started with the `SimpleAuthenticator` is to use TinkerGraph for the "credentials graph" and the "sample" credential graph that is packaged with the server.  Recall that TinkerGraph is an in-memory graph and therefore always starts as "empty" when opened by `GraphFactory`.  To allow TinkerGraph to be used in this "getting started" capacity, Gremlin Server allows for a TinkerGraph-only configuration option called `credentialsDbLocation`.  The following snippet comes from the `conf/gremlin-server-secure.yaml` file packaged with the server:
   
   [source,yaml]
   authentication: {
  
positive.code:     credentialsDb: conf/tinkergraph-empty.properties,
      credentialsDbLocation: data/credentials.kryo}}
  
  This added configuration tells Gremlin Server to look for a gryo file at that location containing the data for the graph which it loads via standard `io` methods.  The limitation is that this read is only performed at the initialization of the server so therefore credentials remain static for the life of the server.
  
  Serialization
  ^^^^^^^^^^^^^
  
negative.code: Security
  ^^^^^^^^
  
  Gremlin Server provides for several features that aid in the security of the graphs that it exposes.  It has built in SSL support and a pluggable authentication framework using link:https://en.wikipedia.org/wiki/Simple_Authentication_and_Security_Layer[SASL] (Simple Authentication and Security Layer).  SSL options are described in the configuration settings table above, so this section will focus on authentication.
  
  By default, Gremlin Server is configured to allow all requests to be processed (i.e. no authentication).  To enable authentication, Gremlin Server must be configured with an `Authenticator` implementation in its YAML file.  Gremlin Server comes packaged with an implementation called `SimpleAuthenticator`.  The `SimpleAuthenticator` implements the `PLAIN` SASL mechanism (i.e. plain text) to authenticate a request.  It validates username/password pairs against a graph database, which must be provided to it as part of the configuration.
  
  [source,yaml]
  authentication: {
  