diff --git a/prudpv0/src/server.rs b/prudpv0/src/server.rs
index 34c7647..a336abb 100644
--- a/prudpv0/src/server.rs
+++ b/prudpv0/src/server.rs
@@ -106,50 +106,55 @@ impl<C: Crypto> Server<C> {
                     .expect("packet malformed in creation"),
             );*/
         let mut inner = conn.inner.lock().await;
-        let seq = inner.server_packet_counter;
-        let packet = new_data_packet(
-            NEED_ACK | RELIABLE,
-            self.param.virtual_port,
-            conn.addr.virtual_port,
-            data,
-            inner.server_packet_counter,
-            conn.session_id,
-            0,
-            &mut inner.crypto_instance,
-            &self.crypto,
-        );
-        inner.server_packet_counter += 1;
+        let pieces = data.chunks(1000);
+        let max_piece = pieces.len() - 1;
+        let mut frag_num = 1;
+        for (i, piece) in pieces.enumerate() {
+            let seq = inner.server_packet_counter;
+            let packet = new_data_packet(
+                NEED_ACK | RELIABLE,
+                (&self).param.virtual_port,
+                conn.addr.virtual_port,
+                piece,
+                inner.server_packet_counter,
+                conn.session_id,
+                if i == max_piece { 0 } else { frag_num },
+                &mut inner.crypto_instance,
+                &(&self).crypto,
+            );
+            inner.server_packet_counter += 1;
 
-        let packet = Arc::new(packet);
-        let packet_ref = Arc::downgrade(&packet);
+            let packet = Arc::new(packet);
+            let packet_ref = Arc::downgrade(&packet);
 
-        inner.unacknowledged_packets.insert(seq, packet);
+            inner.unacknowledged_packets.insert(seq, packet);
 
+            let conn = Arc::downgrade(&conn);
+            let this = Arc::downgrade(&self);
+
+            spawn(async move {
+                for n in 0..5 {
+                    let Some(data) = packet_ref.upgrade() else {
+                        return;
+                    };
+                    let Some(conn) = conn.upgrade() else {
+                        return;
+                    };
+                    let Some(this) = this.upgrade() else {
+                        return;
+                    };
+                    info!("send attempt {}", n);
+
+                    self.socket
+                        .send_to(&data, conn.addr.regular_socket_addr)
+                        .await;
+
+                    break;
+                }
+            });
+            frag_num += 1;
+        }
         drop(inner);
-
-        let conn = Arc::downgrade(&conn);
-        let this = Arc::downgrade(&self);
-
-        spawn(async move {
-            for n in 0..5 {
-                let Some(data) = packet_ref.upgrade() else {
-                    return;
-                };
-                let Some(conn) = conn.upgrade() else {
-                    return;
-                };
-                let Some(this) = this.upgrade() else {
-                    return;
-                };
-                info!("send attempt {}", n);
-
-                self.socket
-                    .send_to(&data, conn.addr.regular_socket_addr)
-                    .await;
-
-                break;
-            }
-        });
     }
     async fn connection_thread(
         self: Arc<Self>,