diff --git a/midea.py b/midea.py
index 541eb38..1d64193 100644
--- a/midea.py
+++ b/midea.py
@@ -4,9 +4,13 @@
 
 # devices = midea_core,discover()
 
-import discover
-
-devices = discover.discover()
+import security;
 
 
+
+secure = security.LocalSecurity()
+
+result = secure.encode_8370(None, security.MSGTYPE_HANDSHAKE_REQUEST)
+
+print(result)
 print(devices)
\ No newline at end of file
diff --git a/src/security.rs b/src/security.rs
index 67eed27..c63cc91 100644
--- a/src/security.rs
+++ b/src/security.rs
@@ -17,14 +17,18 @@ pub enum MsgType {
     ENCRYPTED_REQUEST = 0x6,
 }
 
-pub struct Security;
+#[derive(Debug, Default)]
+pub struct Security {
+    request_count: u32,
+    response_count: u32,
+}
 
 impl Security {
-    pub fn decrypt(data: &mut [u8]) -> &[u8] {
-        const N: u128 = 141661095494369103254425781617665632877;
-        const KEY: [u8; 16] = N.to_be_bytes();
+    const N: u128 = 141661095494369103254425781617665632877;
+    const KEY: [u8; 16] = Self::N.to_be_bytes();
 
-        let array = GenericArray::from(KEY);
+    pub fn decrypt(&self, data: &mut [u8]) -> &[u8] {
+        let array = GenericArray::from(Self::KEY);
         let cipher = Aes128::new(&array);
 
         for chunk in data.chunks_mut(16) {
@@ -35,7 +39,7 @@ impl Security {
         data
     }
 
-    pub fn encode_8370(msg_type: MsgType) -> Result<String> {
+    pub fn encode_8370(&mut self, msg_type: MsgType) -> Result<String> {
         let mut header = hex("83,70")?;
         let mut data: Vec<u8> = Vec::new();