diff --git a/f_func/class._JSON.php b/f_func/class._JSON.php
deleted file mode 100644
index 3ede024b..00000000
--- a/f_func/class._JSON.php
+++ /dev/null
@@ -1,57 +0,0 @@
-<?php
-require(__dir__.'/../vendor/autoload.php');
-
-//NOTE: 그냥 json_encode(), json_decode() 쓰면 안되나?
-class _JSON {
-    public static function Encode($arr) {
-        foreach($arr as $key => $val) {
-            $key = _JSON::AddSlashes($key);
-            if(is_array($val) == true) {
-                $val = json_encode($val);
-            } else {
-                $val = _JSON::AddSlashes($val);
-            }
-            $item[] = "\"{$key}\":\"{$val}\"";
-        }
-        $encoded = '{' . implode(',', $item) . '}';
-        return $encoded;
-    }
-
-    public static function Decode($encoded) {
-        $decoded = substr($encoded, 2, strlen($encoded)-4);
-        $len = strlen($decoded);
-        $s = 0; $e = 0;
-        while($s < $len) {
-            $e = strpos($decoded, '":"', $s);
-            $key = substr($decoded, $s, $e-$s);
-            $s = $e + 3;
-            $e = strpos($decoded, '","', $s);
-            if($e == false) $e = $len;
-            $val = substr($decoded, $s, $e-$s);
-
-            if(substr($val, 0, 2) != '{"') {
-                $s = $e + 3;
-            } else {
-                $e = strpos($decoded, '"}"', $s) + 2;
-                $val = substr($decoded, $s, $e-$s);
-                $s = $e + 3;
-
-                $val = json_decode($val);
-            }
-            $result[$key] = $val;
-        }
-        return $result;
-    }
-
-    public static function AddSlashes($str) {
-        $str = str_replace("\\", "\\\\", $str);
-        $str = str_replace("\"", "\\\"", $str);
-        $str = str_replace("'", "\\'", $str);
-        $str = str_replace("\r\n", "\\n", $str);
-        $str = str_replace("\n", "\\n", $str);
-
-        return $str;
-    }
-}
-
-
diff --git a/f_func/class._Log.php b/f_func/class._Log.php
index 80a173fc..198a3957 100644
--- a/f_func/class._Log.php
+++ b/f_func/class._Log.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 
 class _Log {
     private static $flagLog = true;
diff --git a/f_func/class._Session.php b/f_func/class._Session.php
index 9dd50364..230cd261 100644
--- a/f_func/class._Session.php
+++ b/f_func/class._Session.php
@@ -1,17 +1,18 @@
 <?php
 require(__dir__.'/../vendor/autoload.php');
+use utilphp\util as util;
 
 class _Session {
     public function __construct() {
-        session_cache_limiter('nocache, must_revalidate');
+        //session_cache_limiter('nocache, must_revalidate');
 
         // 세션 변수의 등록
         session_start();
 
         //첫 등장
 
-        if(!isset($_SESSION['ip']) || $_SESSION['ip'] == '') {
-            $_SESSION['ip'] = $_SERVER['REMOTE_ADDR'];
+        if(!util::array_get($_SESSION['ip'])) {
+            $_SESSION['ip'] = util::get_client_ip(true);
             $_SESSION['time'] = time();
         }
     }
@@ -27,7 +28,7 @@ class _Session {
     public function Login($noMember, $idMember, $grade) {
         $_SESSION['noMember'] = $noMember;
         $_SESSION['p_id'] = $idMember;
-        $_SESSION['ip'] = $_SERVER['REMOTE_ADDR'];
+        $_SESSION['ip'] = util::get_client_ip(true);
         $_SESSION['time'] = time();
         $_SESSION['userGrade'] = $grade;
     }
@@ -35,6 +36,8 @@ class _Session {
     public function Logout() {
         unset($_SESSION['noMember']);
         unset($_SESSION['p_id']);
+        unset($_SESSION['time']);
+        unset($_SESSION['userGrade']);
     }
 
     public function IsLoggedIn() {
diff --git a/i_entrance/adminPost.php b/i_entrance/adminPost.php
index 0810e624..38bdb460 100644
--- a/i_entrance/adminPost.php
+++ b/i_entrance/adminPost.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_config/DB.php');
 require_once(ROOT.'/f_config/SESSION.php');
 
diff --git a/i_entrance/logoutPost.php b/i_entrance/logoutPost.php
index a7036288..1f7be99b 100644
--- a/i_entrance/logoutPost.php
+++ b/i_entrance/logoutPost.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_config/DB.php');
 require_once(ROOT.'/f_config/SESSION.php');
 
diff --git a/i_entrance/manage/Get.php b/i_entrance/manage/Get.php
index 608da5d1..4bbcb736 100644
--- a/i_entrance/manage/Get.php
+++ b/i_entrance/manage/Get.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_config/DB.php');
 require_once(ROOT.'/f_config/SESSION.php');
 
diff --git a/i_entrance/manage/deletePost.php b/i_entrance/manage/deletePost.php
index 5e9673c0..3d9be877 100644
--- a/i_entrance/manage/deletePost.php
+++ b/i_entrance/manage/deletePost.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_config/DB.php');
 require_once(ROOT.'/f_config/SESSION.php');
 
diff --git a/i_entrance/manage/passwordPost.php b/i_entrance/manage/passwordPost.php
index 3d004b88..9fa25192 100644
--- a/i_entrance/manage/passwordPost.php
+++ b/i_entrance/manage/passwordPost.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_config/DB.php');
 require_once(ROOT.'/f_config/SESSION.php');
 
diff --git a/i_entrance/manage/quitPost.php b/i_entrance/manage/quitPost.php
index 95e8f878..7fee6087 100644
--- a/i_entrance/manage/quitPost.php
+++ b/i_entrance/manage/quitPost.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_func/class._Time.php');
 require_once(ROOT.'/f_config/DB.php');
 require_once(ROOT.'/f_config/SESSION.php');
diff --git a/i_entrance/member/Get.php b/i_entrance/member/Get.php
index d8d147a8..1defcb58 100644
--- a/i_entrance/member/Get.php
+++ b/i_entrance/member/Get.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_config/DB.php');
 require_once(ROOT.'/f_config/SESSION.php');
 
diff --git a/i_entrance/member/Post.php b/i_entrance/member/Post.php
index 44165fb4..b3749b66 100644
--- a/i_entrance/member/Post.php
+++ b/i_entrance/member/Post.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_config/DB.php');
 require_once(ROOT.'/f_config/SESSION.php');
 
diff --git a/i_entrance/serverListPost.php b/i_entrance/serverListPost.php
index 5fec0049..9f0d6f6c 100644
--- a/i_entrance/serverListPost.php
+++ b/i_entrance/serverListPost.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_config/DB.php');
 require_once(ROOT.'/f_config/SESSION.php');
 
diff --git a/i_login/Post.php b/i_login/Post.php
index c99830ea..b5623542 100644
--- a/i_login/Post.php
+++ b/i_login/Post.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_func/class._Session.php');
 require_once(ROOT.'/f_func/class._String.php');
 require_once(ROOT.'/f_config/DB.php');
@@ -51,7 +50,6 @@ if($member) {
     $response['msg'] = '로그인 실패! ID, PW를 확인해주세요.';
 }
 
-sleep(1);
 echo json_encode($response);
 
 
diff --git a/i_login/findpw/Get.php b/i_login/findpw/Get.php
index 39426836..4c03fb9c 100644
--- a/i_login/findpw/Get.php
+++ b/i_login/findpw/Get.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_config/DB.php');
 
 $registeredCount = getRootDB()->queryFirstField('SELECT COUNT(`NO`) AS CNT FROM MEMBER');
diff --git a/i_login/findpw/Post.php b/i_login/findpw/Post.php
index f1b38fdc..79adf612 100644
--- a/i_login/findpw/Post.php
+++ b/i_login/findpw/Post.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_func/class._Time.php');
 require_once(ROOT.'/f_func/class._String.php');
 require_once(ROOT.'/f_func/class._Validation.php');
diff --git a/i_login/findpw/checkPost.php b/i_login/findpw/checkPost.php
index d855ea89..821740ba 100644
--- a/i_login/findpw/checkPost.php
+++ b/i_login/findpw/checkPost.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_func/class._String.php');
 require_once(ROOT.'/f_func/class._Validation.php');
 require_once(ROOT.'/f_config/DB.php');
diff --git a/i_login/findpw/sendCodePost.php b/i_login/findpw/sendCodePost.php
index e3e1731b..5cb674ac 100644
--- a/i_login/findpw/sendCodePost.php
+++ b/i_login/findpw/sendCodePost.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_func/class._String.php');
 require_once(ROOT.'/f_func/class._Validation.php');
 require_once(ROOT.'/f_func/class._Time.php');
diff --git a/i_login/findpw/verifyCodePost.php b/i_login/findpw/verifyCodePost.php
index 3c6db23c..1bedc151 100644
--- a/i_login/findpw/verifyCodePost.php
+++ b/i_login/findpw/verifyCodePost.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_func/class._Validation.php');
 require_once(ROOT.'/f_func/class._Time.php');
 require_once(ROOT.'/f_config/DB.php');
diff --git a/i_login/join/Get.php b/i_login/join/Get.php
index c6e02b14..36b38af9 100644
--- a/i_login/join/Get.php
+++ b/i_login/join/Get.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_config/DB.php');
 
 $registeredCount = getRootDB()->queryFirstField('SELECT COUNT(`NO`) FROM MEMBER');
diff --git a/i_login/join/Post.php b/i_login/join/Post.php
index 147f008c..e09b3de2 100644
--- a/i_login/join/Post.php
+++ b/i_login/join/Post.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_func/class._Time.php');
 require_once(ROOT.'/f_func/class._String.php');
 require_once(ROOT.'/f_func/class._Validation.php');
diff --git a/i_login/join/checkPost.php b/i_login/join/checkPost.php
index f92c5f02..463fdd01 100644
--- a/i_login/join/checkPost.php
+++ b/i_login/join/checkPost.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_func/class._String.php');
 require_once(ROOT.'/f_func/class._Validation.php');
 require_once(ROOT.'/f_config/DB.php');
diff --git a/i_login/join/sendCodePost.php b/i_login/join/sendCodePost.php
index e3e1731b..5cb674ac 100644
--- a/i_login/join/sendCodePost.php
+++ b/i_login/join/sendCodePost.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_func/class._String.php');
 require_once(ROOT.'/f_func/class._Validation.php');
 require_once(ROOT.'/f_func/class._Time.php');
diff --git a/i_login/join/verifyCodePost.php b/i_login/join/verifyCodePost.php
index 9b2682d4..bbc38cbc 100644
--- a/i_login/join/verifyCodePost.php
+++ b/i_login/join/verifyCodePost.php
@@ -1,6 +1,5 @@
 <?php
 require_once('_common.php');
-require_once(ROOT.'/f_func/class._JSON.php');
 require_once(ROOT.'/f_func/class._Validation.php');
 require_once(ROOT.'/f_func/class._Time.php');
 require_once(ROOT.'/f_config/DB.php');