diff --git a/app/controllers/report_controller.rb b/app/controllers/report_controller.rb
--- a/app/controllers/report_controller.rb
+++ b/app/controllers/report_controller.rb
@@ -215,4 +215,41 @@
     @struggle = @struggle[0..50]
   end
 
+
+  def multiple_login
+    #user with multiple IP
+    raw = Submission.joins(:user).joins(:problem).where("problems.available != 0").group("login,ip_address").order(:login)
+    last,count = 0,0
+    first = 0
+    @users = []
+    raw.each do |r|
+      if last != r.user.login
+        count = 1
+        last = r.user.login
+        first = r
+      else
+        @users << first if count == 1
+        @users << r
+        count += 1
+      end
+    end
+
+    #IP with multiple user
+    raw = Submission.joins(:user).joins(:problem).where("problems.available != 0").group("login,ip_address").order(:ip_address)
+    last,count = 0,0
+    first = 0
+    @ip = []
+    raw.each do |r|
+      if last != r.ip_address
+        count = 1
+        last = r.ip_address
+        first = r
+      else
+        @ip << first if count == 1
+        @ip << r
+        count += 1
+      end
+    end
+  end
+
 end
diff --git a/app/controllers/user_admin_controller.rb b/app/controllers/user_admin_controller.rb
--- a/app/controllers/user_admin_controller.rb
+++ b/app/controllers/user_admin_controller.rb
@@ -150,6 +150,12 @@
       end
       @scorearray << ustat
     end
+    if params[:commit] == 'download csv' then
+      csv = gen_csv_from_scorearray(@scorearray,@problems)
+      send_data csv, filename: 'last_score.csv'
+    else
+      render template: 'user_admin/user_stat'
+    end
   end
 
   def user_stat_max
diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -13,7 +13,7 @@
       append_to menu_items, '[Problems]', 'problems', 'index'
       append_to menu_items, '[Users]', 'user_admin', 'index'
       append_to menu_items, '[Results]', 'user_admin', 'user_stat'
-      append_to menu_items, '[Report]', 'report', 'login_stat'
+      append_to menu_items, '[Report]', 'report', 'multiple_login'
       append_to menu_items, '[Graders]', 'graders', 'list'
       append_to menu_items, '[Contests]', 'contest_management', 'index'
       append_to menu_items, '[Sites]', 'sites', 'index'
diff --git a/app/views/problems/stat.html.haml b/app/views/problems/stat.html.haml
--- a/app/views/problems/stat.html.haml
+++ b/app/views/problems/stat.html.haml
@@ -34,6 +34,7 @@
         %th Submitted_at
         %th Points
         %th comment
+        %th IP
     %tbody
       - row_odd,curr = true,''
       - @submissions.each do |sub|
@@ -46,6 +47,7 @@
           %td= time_ago_in_words(sub.submitted_at) + " ago"
           %td= sub.points
           %td.fix-width= sub.grader_comment
+          %td= sub.ip_address
 - else
   No submission
 
diff --git a/app/views/report/_report_menu.html.haml b/app/views/report/_report_menu.html.haml
--- a/app/views/report/_report_menu.html.haml
+++ b/app/views/report/_report_menu.html.haml
@@ -5,3 +5,4 @@
   = link_to '[Hall of Fame]', :action => 'problem_hof'
   = link_to '[Struggle]', :action => 'stuck'
   = link_to '[Login]', :action => 'login_stat'
+  = link_to '[Multiple Login]', :action => 'multiple_login'
diff --git a/app/views/report/multiple_login.html.haml b/app/views/report/multiple_login.html.haml
new file mode 100644
--- /dev/null
+++ b/app/views/report/multiple_login.html.haml
@@ -0,0 +1,37 @@
+- content_for :header do
+  = stylesheet_link_tag 'tablesorter-theme.cafe'
+  = javascript_include_tag 'local_jquery'
+
+%h1 Login status
+
+=render partial: 'report_menu'
+
+Checking for all submissions with the currently available problem
+
+%h2 Users with Multiple IP
+%table.tablesorter-cafe#my_table
+  %thead
+    %tr
+      %th login
+      %th full name
+      %th IP
+  %tbody
+    - @users.each do |l|
+      %tr{class: cycle('info-even','info-odd')}
+        %td= link_to l.user.login, controller: 'users', action: 'profile', id: l[:id]
+        %td= l.user.full_name
+        %td= l[:ip_address]
+
+%h2 IP with multiple users
+%table.tablesorter-cafe#my_table
+  %thead
+    %tr
+      %th IP
+      %th login
+      %th full name
+  %tbody
+    - @ip.each do |l|
+      %tr{class: cycle('info-even','info-odd')}
+        %td= l[:ip_address]
+        %td= link_to l.user.login, controller: 'users', action: 'profile', id: l[:id]
+        %td= l.user.full_name