diff --git a/e2e-test/src/test.rs b/e2e-test/src/test.rs
index ee23729..373ed72 100644
--- a/e2e-test/src/test.rs
+++ b/e2e-test/src/test.rs
@@ -93,16 +93,9 @@ mod tests {
 
         let port = 1812;
 
-        let mut server = Server::listen(
-            "0.0.0.0",
-            port,
-            1500,
-            true,
-            MyRequestHandler {},
-            MySecretProvider {},
-        )
-        .await
-        .unwrap();
+        let mut server = Server::listen("0.0.0.0", port, MyRequestHandler {}, MySecretProvider {})
+            .await
+            .unwrap();
 
         let server_proc = tokio::spawn(async move {
             server.run(receiver).await.unwrap();
@@ -140,8 +133,6 @@ mod tests {
         let mut server = Server::listen(
             "0.0.0.0",
             port,
-            1500,
-            true,
             LongTimeTakingHandler {},
             MySecretProvider {},
         )
diff --git a/examples/server.rs b/examples/server.rs
index 6c4afd3..29568ac 100644
--- a/examples/server.rs
+++ b/examples/server.rs
@@ -18,16 +18,11 @@ async fn main() {
     env_logger::init();
 
     // start UDP listening
-    let mut server = Server::listen(
-        "0.0.0.0",
-        1812,
-        1500,
-        false,
-        MyRequestHandler {},
-        MySecretProvider {},
-    )
-    .await
-    .unwrap();
+    let mut server = Server::listen("0.0.0.0", 1812, MyRequestHandler {}, MySecretProvider {})
+        .await
+        .unwrap();
+    server.set_buffer_size(1500); // default value: 1500
+    server.set_skip_authenticity_validation(false); // default value: false
 
     // once it has reached here, a RADIUS server is now ready
     info!(
diff --git a/radius/src/server.rs b/radius/src/server.rs
index 03240f9..bdc69aa 100644
--- a/radius/src/server.rs
+++ b/radius/src/server.rs
@@ -14,6 +14,9 @@ use crate::core::request::Request;
 use std::fmt::Debug;
 use std::marker::PhantomData;
 
+const DEFAULT_BUFFER_SIZE: usize = 1500;
+const DEFAULT_SKIP_AUTHENTICITY_VALIDATION: bool = false;
+
 /// A basic implementation of the RADIUS server.
 ///
 /// ## Example Usage
@@ -47,15 +50,11 @@ impl<X, E: Debug, T: RequestHandler<X, E>, U: SecretProvider> Server<X, E, T, U>
     ///
     /// - `host` - a host to listen (e.g. `0.0.0.0`)
     /// - `port` - a port number to listen (e.g. `1812`)
-    /// - `buf_size` - a buffer size for receiving the request payload (e.g. `1500`)
-    /// - `skip_authenticity_validation` - a flag to specify whether to skip the authenticity validation or not.
     /// - `request_handler` - a request handler for the RADIUS requests.
     /// - `secret_provider` - a provider for shared-secret value.
     pub async fn listen(
         host: &str,
         port: u16,
-        buf_size: usize,
-        skip_authenticity_validation: bool,
         request_handler: T,
         secret_provider: U,
     ) -> Result<Self, io::Error> {
@@ -68,8 +67,8 @@ impl<X, E: Debug, T: RequestHandler<X, E>, U: SecretProvider> Server<X, E, T, U>
         let conn_arc = Arc::new(conn);
 
         Ok(Server {
-            skip_authenticity_validation,
-            buf_size,
+            skip_authenticity_validation: DEFAULT_SKIP_AUTHENTICITY_VALIDATION,
+            buf_size: DEFAULT_BUFFER_SIZE,
             conn_arc,
             request_handler_arc,
             secret_provider_arc,
@@ -96,6 +95,16 @@ impl<X, E: Debug, T: RequestHandler<X, E>, U: SecretProvider> Server<X, E, T, U>
         }
     }
 
+    /// Set a buffer size for receiving the request payload (default: `1500`).
+    pub fn set_buffer_size(&mut self, buf_size: usize) {
+        self.buf_size = buf_size;
+    }
+
+    /// Set a flag to specify whether to skip the authenticity validation or not (default: `false`).
+    pub fn set_skip_authenticity_validation(&mut self, skip_authenticity_validation: bool) {
+        self.skip_authenticity_validation = skip_authenticity_validation;
+    }
+
     /// Returns the listening address.
     pub fn get_listen_address(&self) -> io::Result<SocketAddr> {
         self.conn_arc.local_addr()