diff --git a/tuic-client/src/connection.rs b/tuic-client/src/connection.rs
index 7d14e8c..84bf348 100644
--- a/tuic-client/src/connection.rs
+++ b/tuic-client/src/connection.rs
@@ -251,7 +251,7 @@ impl Connection {
     }
 
     async fn authenticate(self) {
-        match self.model.authenticate([0; 8]).await {
+        match self.model.authenticate([0; 32]).await {
             Ok(()) => {}
             Err(err) => eprintln!("{err}"),
         }
diff --git a/tuic-quinn/src/lib.rs b/tuic-quinn/src/lib.rs
index 8c94025..29057ba 100644
--- a/tuic-quinn/src/lib.rs
+++ b/tuic-quinn/src/lib.rs
@@ -102,7 +102,7 @@ impl Connection<side::Client> {
         }
     }
 
-    pub async fn authenticate(&self, token: [u8; 8]) -> Result<(), Error> {
+    pub async fn authenticate(&self, token: [u8; 32]) -> Result<(), Error> {
         let model = self.model.send_authenticate(token);
         let mut send = self.conn.open_uni().await?;
         model.header().async_marshal(&mut send).await?;
@@ -388,7 +388,7 @@ impl Packet {
 
 #[non_exhaustive]
 pub enum Task {
-    Authenticate([u8; 8]),
+    Authenticate([u8; 32]),
     Connect(Connect),
     Packet(Packet),
     Dissociate(u16),
diff --git a/tuic/src/model/authenticate.rs b/tuic/src/model/authenticate.rs
index e02940d..9dcb965 100644
--- a/tuic/src/model/authenticate.rs
+++ b/tuic/src/model/authenticate.rs
@@ -11,7 +11,7 @@ pub struct Tx {
 }
 
 impl Authenticate<side::Tx> {
-    pub(super) fn new(token: [u8; 8]) -> Self {
+    pub(super) fn new(token: [u8; 32]) -> Self {
         Self {
             inner: Side::Tx(Tx {
                 header: Header::Authenticate(AuthenticateHeader::new(token)),
@@ -27,18 +27,18 @@ impl Authenticate<side::Tx> {
 }
 
 pub struct Rx {
-    token: [u8; 8],
+    token: [u8; 32],
 }
 
 impl Authenticate<side::Rx> {
-    pub(super) fn new(token: [u8; 8]) -> Self {
+    pub(super) fn new(token: [u8; 32]) -> Self {
         Self {
             inner: Side::Rx(Rx { token }),
             _marker: side::Rx,
         }
     }
 
-    pub fn token(&self) -> [u8; 8] {
+    pub fn token(&self) -> [u8; 32] {
         let Side::Rx(rx) = &self.inner else { unreachable!() };
         rx.token
     }
diff --git a/tuic/src/model/mod.rs b/tuic/src/model/mod.rs
index 5ce3c71..9e66fe1 100644
--- a/tuic/src/model/mod.rs
+++ b/tuic/src/model/mod.rs
@@ -50,7 +50,7 @@ where
         }
     }
 
-    pub fn send_authenticate(&self, token: [u8; 8]) -> Authenticate<side::Tx> {
+    pub fn send_authenticate(&self, token: [u8; 32]) -> Authenticate<side::Tx> {
         Authenticate::<side::Tx>::new(token)
     }
 
diff --git a/tuic/src/protocol/authenticate.rs b/tuic/src/protocol/authenticate.rs
index b17f791..9879241 100644
--- a/tuic/src/protocol/authenticate.rs
+++ b/tuic/src/protocol/authenticate.rs
@@ -1,21 +1,21 @@
 // +-------+
 // | TOKEN |
 // +-------+
-// |   8   |
+// |  32   |
 // +-------+
 #[derive(Clone, Debug)]
 pub struct Authenticate {
-    token: [u8; 8],
+    token: [u8; 32],
 }
 
 impl Authenticate {
     const TYPE_CODE: u8 = 0x00;
 
-    pub const fn new(token: [u8; 8]) -> Self {
+    pub const fn new(token: [u8; 32]) -> Self {
         Self { token }
     }
 
-    pub fn token(&self) -> [u8; 8] {
+    pub fn token(&self) -> [u8; 32] {
         self.token
     }
 
@@ -24,11 +24,11 @@ impl Authenticate {
     }
 
     pub fn len(&self) -> usize {
-        8
+        32
     }
 }
 
-impl From<Authenticate> for ([u8; 8],) {
+impl From<Authenticate> for ([u8; 32],) {
     fn from(auth: Authenticate) -> Self {
         (auth.token,)
     }
diff --git a/tuic/src/unmarshal.rs b/tuic/src/unmarshal.rs
index 7b4b48a..ca037c2 100644
--- a/tuic/src/unmarshal.rs
+++ b/tuic/src/unmarshal.rs
@@ -164,14 +164,14 @@ impl Address {
 impl Authenticate {
     #[cfg(feature = "async_marshal")]
     async fn async_read(s: &mut (impl AsyncRead + Unpin)) -> Result<Self, UnmarshalError> {
-        let mut buf = [0; 8];
+        let mut buf = [0; 32];
         s.read_exact(&mut buf).await?;
         Ok(Self::new(buf))
     }
 
     #[cfg(feature = "marshal")]
     fn read(s: &mut impl Read) -> Result<Self, UnmarshalError> {
-        let mut buf = [0; 8];
+        let mut buf = [0; 32];
         s.read_exact(&mut buf)?;
         Ok(Self::new(buf))
     }