diff --git a/OSTLibrary/Securities/AES256.cs b/OSTLibrary/Securities/AES256.cs
index 0cc70dd..11b55de 100644
--- a/OSTLibrary/Securities/AES256.cs
+++ b/OSTLibrary/Securities/AES256.cs
@@ -1,62 +1,54 @@
-using System;
-using System.Text;
+using System.Text;
 using System.Security.Cryptography;
 using System.IO;
 
 namespace OSTLibrary.Securities
 {
-    class AESEncrypt
+    // 참조사이트-https://h5bak.tistory.com/148 
+    public static class AES256
     {
-        private SHA256Managed sha256Managed = new SHA256Managed();
-        private RijndaelManaged aes = new RijndaelManaged();
-
-        public AESEncrypt()
+        private static string key = "qlalfqjsgh@djfuqekGG";
+        private static SHA256Managed sha256Managed = new SHA256Managed();
+        private static RijndaelManaged aes = new RijndaelManaged()
         {
-            aes.KeySize = 256;
-            aes.BlockSize = 128;
-            aes.Mode = CipherMode.CBC;
-            aes.Padding = PaddingMode.PKCS7;
-        }
+            KeySize = 256,
+            BlockSize = 128,
+            Mode = CipherMode.CBC,
+            Padding = PaddingMode.PKCS7
+        };
 
-
-        //AES_256 암호화
-        public byte[] AESEncrypt256(byte[] encryptData, String password)
+        public static byte[] Encrypt(byte[] data)
         {
             // Salt는 비밀번호의 길이를 SHA256 해쉬값으로 한다.
-            var salt = sha256Managed.ComputeHash(Encoding.UTF8.GetBytes(password.Length.ToString()));
-            Console.WriteLine("Salt(Base64) : " + Convert.ToBase64String(salt));
+            var salt = sha256Managed.ComputeHash(Encoding.UTF8.GetBytes(key.Length.ToString()));
 
 
             //PBKDF2(Password-Based Key Derivation Function)
             //반복은 65535번
-            var PBKDF2Key = new Rfc2898DeriveBytes(password, salt, 65535, HashAlgorithmName.SHA256);
+            var PBKDF2Key = new Rfc2898DeriveBytes(key, salt, 65535, HashAlgorithmName.SHA256);
             var secretKey = PBKDF2Key.GetBytes(aes.KeySize / 8);
             var iv = PBKDF2Key.GetBytes(aes.BlockSize / 8);
 
-            Console.WriteLine("SecretKey(Base64) : " + Convert.ToBase64String(secretKey));
-            Console.WriteLine("IV(Base64) : " + Convert.ToBase64String(iv));
-
             byte[] xBuff = null;
             using (var ms = new MemoryStream())
             {
                 using (var cs = new CryptoStream(ms, aes.CreateEncryptor(secretKey, iv), CryptoStreamMode.Write))
                 {
-                    cs.Write(encryptData, 0, encryptData.Length);
+                    cs.Write(data, 0, data.Length);
                 }
                 xBuff = ms.ToArray();
             }
             return xBuff;
         }
 
-        //AES_256 복호화
-        public byte[] AESDecrypt256(byte[] decryptData, String password)
+        public static byte[] Decrypt(byte[] data)
         {
             // Salt는 비밀번호의 길이를 SHA256 해쉬값으로 한다.
-            var salt = sha256Managed.ComputeHash(Encoding.UTF8.GetBytes(password.Length.ToString()));
+            var salt = sha256Managed.ComputeHash(Encoding.UTF8.GetBytes(key.Length.ToString()));
 
             //PBKDF2(Password-Based Key Derivation Function)
             //반복은 65535번
-            var PBKDF2Key = new Rfc2898DeriveBytes(password, salt, 65535, HashAlgorithmName.SHA256);
+            var PBKDF2Key = new Rfc2898DeriveBytes(key, salt, 65535, HashAlgorithmName.SHA256);
             var secretKey = PBKDF2Key.GetBytes(aes.KeySize / 8);
             var iv = PBKDF2Key.GetBytes(aes.BlockSize / 8);
 
@@ -65,30 +57,11 @@ public byte[] AESDecrypt256(byte[] decryptData, String password)
             {
                 using (var cs = new CryptoStream(ms, aes.CreateDecryptor(secretKey, iv), CryptoStreamMode.Write))
                 {
-                    cs.Write(decryptData, 0, decryptData.Length);
+                    cs.Write(data, 0, data.Length);
                 }
                 xBuff = ms.ToArray();
             }
             return xBuff;
         }
     }
-    // 참조사이트-https://h5bak.tistory.com/148 
-    public static class AES256
-    {
-        public static byte[] Encrypt(byte[] data, string key)
-        {
-            AESEncrypt aes = new AESEncrypt();
-            return aes.AESEncrypt256(data, key);
-        }
-        public static string Encrypt(string data, string key)
-            => Encoding.Default.GetString(Encrypt(Encoding.Default.GetBytes(data), key));
-
-        public static byte[] Decrypt(byte[] data, string key)
-        {
-            AESEncrypt aes = new AESEncrypt();
-            return aes.AESDecrypt256(data, key);
-        }
-        public static string Decrypt(string data, string key)
-            => Encoding.Default.GetString(Decrypt(Encoding.Default.GetBytes(data), key));
-    }
 }
\ No newline at end of file
diff --git a/Server/Classes/Client.cs b/Server/Classes/Client.cs
index ac039e7..707b267 100644
--- a/Server/Classes/Client.cs
+++ b/Server/Classes/Client.cs
@@ -270,6 +270,7 @@ public void Send(Packet packet)
                 ns.Flush();
             }
         }
+
         void Log(string type, string content)
         {
             Program.Log(employee.id, type, content);