diff --git a/Gemfile b/Gemfile
index 9bef8cc..4000259 100644
--- a/Gemfile
+++ b/Gemfile
@@ -4,6 +4,8 @@ source 'https://rubygems.org'
 gem 'rails', '~> 4.1.0'
 gem 'sanitize'
 
+gem 'savon', '~> 2.2.0'
+
 #assets and templates
 gem 'sass-rails', '~> 4.0.2'
 gem 'uglifier', '>= 1.3.0'
diff --git a/app/controllers/sessions_controller.rb b/app/controllers/sessions_controller.rb
index 9c4071c..d3c7e2b 100644
--- a/app/controllers/sessions_controller.rb
+++ b/app/controllers/sessions_controller.rb
@@ -1,5 +1,7 @@
 class SessionsController < ApplicationController
   layout "authentication"
+
+  require 'savon'
   
   def new
     if session[:user_id]
@@ -8,23 +10,83 @@ class SessionsController < ApplicationController
   end
 
   def create
-    user = User.find_by(user_name: params[:user_name]) rescue nil
-    if (user && user.authenticate(params[:password]) && user.is_confirmed?.eql?(true))
-      if user.is_approved? || user.is_admin?
-        session[:user_id] = user.id
-        session[:login_referer] = nil
-        if params[:referer_url]
-          redirect_to URI.parse(params[:referer_url]).path
+
+    @SYS_USER = "rulingcom"
+    @SYS_PASS = "pxm87912tkx"
+    @LDAP_USER = params[:user_name]
+    @LDAP_PASS = params[:password]
+
+    if @LDAP_USER == 'rulingcom'
+
+      user = User.find_by(user_name: @LDAP_USER) rescue nil
+      if (user && user.authenticate(@LDAP_PASS) && user.is_confirmed?.eql?(true))
+        if user.is_approved? || user.is_admin?
+          session[:user_id] = user.id
+          session[:login_referer] = nil
+          if params[:referer_url]
+            redirect_to URI.parse(params[:referer_url]).path
+          else
+            redirect_to admin_dashboards_path
+          end
         else
-          redirect_to admin_dashboards_path
+          flash.now.alert = "User not approved."
+          render "new"
         end
       else
-        flash.now.alert = "User not approved."
+        flash.now.alert = "Invalid username or password"
         render "new"
       end
+
     else
-      flash.now.alert = "Invalid username or password"
-      render "new"
+          
+      errors = ["很抱歉,您無此權限或帳號登入本站,請洽本站管理員", "Sorry, you don't have the account or authority to login. Please contact the website administrator."] 
+
+      client = Savon.client(wsdl: 'http://ap.ydu.edu.tw/LDAP_WS/RulingcomDataService.asmx?wsdl',filters: [:SYS_USER, :SYS_PASS, :LDAP_USER, :LDAP_PASS])
+
+      client.operations
+      
+      response = client.call(:login_chk, message: { 
+        "SYS_USER" => @SYS_USER, 
+        "SYS_PASS" =>  @SYS_PASS,
+        "LDAP_USER" => @LDAP_USER, 
+        "LDAP_PASS" => @LDAP_PASS, 
+        "User_IP" => request.remote_ip
+      })
+
+      @datas = response.body[:login_chk_response][:login_chk_result][:string]
+
+      if !@datas[0].blank? and ( @datas[0] == 'P' or @datas[0] == 'U' ) #使用者帳號回傳P，單位帳號回傳U
+
+        user = User.find_by(user_name: @LDAP_USER) rescue nil
+
+        if !user.blank?
+
+          if user.is_approved? || user.is_admin?
+            session[:user_id] = user.id
+            session[:login_referer] = nil
+            if params[:referer_url]
+              redirect_to URI.parse(params[:referer_url]).path
+            else
+              redirect_to admin_dashboards_path
+            end
+          else
+            flash.now.alert = "User not approved."
+            render "new"
+          end
+
+        else #認證通過無帳號不通過
+
+          flash.now.alert = errors.join("<br/>").html_safe
+          render "new"
+
+        end
+
+      else
+
+        flash.now.alert = errors.join("<br/>").html_safe
+        render "new"
+
+      end
     end
   end
 
diff --git a/app/models/user.rb b/app/models/user.rb
index e274c6a..f25160d 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -24,8 +24,8 @@ class User
   has_one :desktop, :dependent => :destroy
 
 
-  validates :user_name, uniqueness: true
-  validates :password, :on => :create, length: {:in => 8..20}
+  validates :user_name, uniqueness: true, length: {:minimum => 2, :maximum => 50, :message => I18n.t("users.user_id_length") }
+  validates :password, presence: true, :on => :create, length: {:in => 8..20}
 
   #Add getter and setter for email virtual field
   attr_accessor :email, :first_name, :last_name
diff --git a/config/locales/en.yml b/config/locales/en.yml
index c45c6e3..ba561a1 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -659,9 +659,9 @@ en:
     sex: Gender
     gender: Gender
     user_id: User Account
-    user_id_note: Should be more than 3 characters and less than 50 characters
+    user_id_note: Should be more than 2 characters and less than 50 characters
     user_id_not_null: User account cannot be null 
-    user_id_length: User account should be more than 3 characters 
+    user_id_length: User account should be more than 2 characters 
     user_id_error: Someone already use that user account 
     user_basic_id_form: Account Info.
     user_basic_data: Personal Profile
diff --git a/config/locales/zh_tw.yml b/config/locales/zh_tw.yml
index c501af4..7bc553a 100644
--- a/config/locales/zh_tw.yml
+++ b/config/locales/zh_tw.yml
@@ -650,9 +650,9 @@ zh_tw:
     sex: 性別
     gender: 性別
     user_id: 使用者帳號
-    user_id_note: 需介於3個字元至50個字元之間
+    user_id_note: 需介於2個字元至50個字元之間
     user_id_not_null: 使用者帳號不能是空值
-    user_id_length: 使用者帳號至少需要3個字元
+    user_id_length: 使用者帳號至少需要2個字元
     user_id_error: 該使用者帳號已被使用
     user_basic_id_form: 帳號資料
     user_basic_data: 個人資料