@Override
  public ServerSecurityService getServerSecurityService() throws InstantiationException {
    return new AmbryServerSecurityService(serverConfig, serverMetrics);
  }
Default implementation of {@link ServerSecurityServiceFactory} for Ambry
<p/>
Returns a new instance of {@link AmbryServerSecurityService} on {@link #getServerSecurityService()} call.
ambry-server/src/main/java/com/github/ambry/server/AmbryServerSecurityServiceFactory.java