docs: @Override
      public void sendSubscriptionRequest(String fromParticipantId,
                                          Set<DiscoveryEntryWithMetaInfo> toDiscoveryEntries,
                                          SubscriptionRequest subscriptionRequest,
                                          MessagingQos messagingQos) {
          for (DiscoveryEntryWithMetaInfo toDiscoveryEntry : toDiscoveryEntries) {
              MutableMessage message = messageFactory.createSubscriptionRequest(fromParticipantId,
                                                                                toDiscoveryEntry.getParticipantId(),
                                                                                subscriptionRequest,
                                                                                messagingQos);
              message.setLocalMessage(toDiscoveryEntry.getIsLocal());
  
              if (subscriptionRequest instanceof MulticastSubscriptionRequest) {
                  String multicastId = ((MulticastSubscriptionRequest) subscriptionRequest).getMulticastId();
                  messageRouter.addMulticastReceiver(multicastId, fromParticipantId, toDiscoveryEntry.getParticipantId());
              }
              logger.debug("Send SubscriptionRequest: subscriptionId: {}, messageId: {}, proxy participantId: {}, provider participantId: {}",
                           subscriptionRequest.getSubscriptionId(),
                           message.getId(),
                           fromParticipantId,
                           toDiscoveryEntry.getParticipantId());
              messageSender.sendMessage(message);
          }
      }