use proper mixing delay instead of poisson delay in cover traffic (#6269)

common/client-core/src/client/cover_traffic_stream.rs

@@ -32,9 +32,12 @@ where
     /// Key used to encrypt and decrypt content of an ACK packet.
     ack_key: Arc<AckKey>,
 
-    /// Average delay an acknowledgement packet is going to get delay at a single mixnode.
+    /// Average delay an acknowledgement packet is going to get delayed at a single mixnode.
     average_ack_delay: Duration,
 
+    /// Average delay a forward packet is going to get delayed at a single mixnode.
+    average_packet_delay: Duration,
+
     /// Defines configuration options related to cover traffic.
     cover_traffic: config::CoverTraffic,
 
@@ -122,6 +125,7 @@ impl LoopCoverTrafficStream<OsRng> {
         LoopCoverTrafficStream {
             ack_key,
             average_ack_delay,
+            average_packet_delay: traffic_config.average_packet_delay,
             cover_traffic: cover_config,
             next_delay,
             mix_tx,
@@ -187,7 +191,7 @@ impl LoopCoverTrafficStream<OsRng> {
             &self.ack_key,
             &self.our_full_destination,
             self.average_ack_delay,
-            self.cover_traffic.loop_cover_traffic_average_delay,
+            self.average_packet_delay,
             cover_traffic_packet_size,
             self.packet_type,
         ) {