diff --git a/catchain/catchain-receiver.cpp b/catchain/catchain-receiver.cpp
index edef9065..a6160383 100644
--- a/catchain/catchain-receiver.cpp
+++ b/catchain/catchain-receiver.cpp
@@ -526,10 +526,12 @@ void CatChainReceiverImpl::start_up() {
   for (td::uint32 i = 0; i < get_sources_cnt(); i++) {
     root_keys.emplace(get_source(i)->get_hash(), OVERLAY_MAX_ALLOWED_PACKET_SIZE);
   }
-  td::actor::send_closure(overlay_manager_, &overlay::Overlays::create_private_overlay,
+  overlay::OverlayOptions overlay_options;
+  overlay_options.broadcast_speed_multiplier_ = opts_.broadcast_speed_multiplier;
+  td::actor::send_closure(overlay_manager_, &overlay::Overlays::create_private_overlay_ex,
                           get_source(local_idx_)->get_adnl_id(), overlay_full_id_.clone(), std::move(ids),
                           make_callback(), overlay::OverlayPrivacyRules{0, 0, std::move(root_keys)},
-                          R"({ "type": "catchain" })");
+                          R"({ "type": "catchain" })", std::move(overlay_options));
 
   CHECK(root_block_);
 
diff --git a/overlay/overlay-fec.cpp b/overlay/overlay-fec.cpp
index b29fce22..817d3b7c 100644
--- a/overlay/overlay-fec.cpp
+++ b/overlay/overlay-fec.cpp
@@ -32,7 +32,7 @@ void OverlayOutboundFecBroadcast::alarm() {
                             fec_type_.size(), flags_, std::move(X.data), X.id, fec_type_, date_);
   }
 
-  alarm_timestamp() = td::Timestamp::in(0.010);
+  alarm_timestamp() = td::Timestamp::in(delay_);
 
   if (seqno_ >= to_send_) {
     stop();
@@ -46,8 +46,9 @@ void OverlayOutboundFecBroadcast::start_up() {
 
 OverlayOutboundFecBroadcast::OverlayOutboundFecBroadcast(td::BufferSlice data, td::uint32 flags,
                                                          td::actor::ActorId<OverlayImpl> overlay,
-                                                         PublicKeyHash local_id)
+                                                         PublicKeyHash local_id, double speed_multiplier)
     : flags_(flags) {
+  delay_ /= speed_multiplier;
   CHECK(data.size() <= (1 << 27));
   local_id_ = local_id;
   overlay_ = std::move(overlay);
@@ -63,9 +64,10 @@ OverlayOutboundFecBroadcast::OverlayOutboundFecBroadcast(td::BufferSlice data, t
 }
 
 td::actor::ActorId<OverlayOutboundFecBroadcast> OverlayOutboundFecBroadcast::create(
-    td::BufferSlice data, td::uint32 flags, td::actor::ActorId<OverlayImpl> overlay, PublicKeyHash local_id) {
-  return td::actor::create_actor<OverlayOutboundFecBroadcast>(td::actor::ActorOptions().with_name("bcast"),
-                                                              std::move(data), flags, overlay, local_id)
+    td::BufferSlice data, td::uint32 flags, td::actor::ActorId<OverlayImpl> overlay, PublicKeyHash local_id,
+    double speed_multiplier) {
+  return td::actor::create_actor<OverlayOutboundFecBroadcast>(
+             td::actor::ActorOptions().with_name("bcast"), std::move(data), flags, overlay, local_id, speed_multiplier)
       .release();
 }
 
diff --git a/overlay/overlay-fec.hpp b/overlay/overlay-fec.hpp
index a9cc3634..b72e830e 100644
--- a/overlay/overlay-fec.hpp
+++ b/overlay/overlay-fec.hpp
@@ -37,6 +37,7 @@ class OverlayOutboundFecBroadcast : public td::actor::Actor {
   PublicKeyHash local_id_;
   Overlay::BroadcastDataHash data_hash_;
   td::uint32 flags_ = 0;
+  double delay_ = 0.010;
   td::int32 date_;
   std::unique_ptr<td::fec::Encoder> encoder_;
   td::actor::ActorId<OverlayImpl> overlay_;
@@ -45,9 +46,9 @@ class OverlayOutboundFecBroadcast : public td::actor::Actor {
  public:
   static td::actor::ActorId<OverlayOutboundFecBroadcast> create(td::BufferSlice data, td::uint32 flags,
                                                                 td::actor::ActorId<OverlayImpl> overlay,
-                                                                PublicKeyHash local_id);
+                                                                PublicKeyHash local_id, double speed_multiplier = 1.0);
   OverlayOutboundFecBroadcast(td::BufferSlice data, td::uint32 flags, td::actor::ActorId<OverlayImpl> overlay,
-                              PublicKeyHash local_id);
+                              PublicKeyHash local_id, double speed_multiplier = 1.0);
 
   void alarm() override;
   void start_up() override;
diff --git a/overlay/overlay.cpp b/overlay/overlay.cpp
index 429c6a9c..30a40b1c 100644
--- a/overlay/overlay.cpp
+++ b/overlay/overlay.cpp
@@ -63,7 +63,7 @@ td::actor::ActorOwn<Overlay> Overlay::create_private(
   return td::actor::create_actor<OverlayImpl>(
       overlay_actor_name(overlay_id), keyring, adnl, manager, dht_node, local_id, std::move(overlay_id),
       OverlayType::FixedMemberList, std::move(nodes), std::vector<PublicKeyHash>(), OverlayMemberCertificate{},
-      std::move(callback), std::move(rules), std::move(scope));
+      std::move(callback), std::move(rules), std::move(scope), std::move(opts));
 }
 
 td::actor::ActorOwn<Overlay> Overlay::create_semiprivate(
@@ -99,6 +99,7 @@ OverlayImpl::OverlayImpl(td::actor::ActorId<keyring::Keyring> keyring, td::actor
   overlay_id_ = id_full_.compute_short_id();
   frequent_dht_lookup_ = opts_.frequent_dht_lookup_;
   peer_list_.local_member_flags_ = opts_.local_overlay_member_flags_;
+  opts_.broadcast_speed_multiplier_ = std::max(opts_.broadcast_speed_multiplier_, 1e-9);
 
   VLOG(OVERLAY_INFO) << this << ": creating";
 
@@ -490,7 +491,8 @@ void OverlayImpl::send_broadcast_fec(PublicKeyHash send_as, td::uint32 flags, td
     VLOG(OVERLAY_WARNING) << "broadcast source certificate is invalid";
     return;
   }
-  OverlayOutboundFecBroadcast::create(std::move(data), flags, actor_id(this), send_as);
+  OverlayOutboundFecBroadcast::create(std::move(data), flags, actor_id(this), send_as,
+                                      opts_.broadcast_speed_multiplier_);
 }
 
 void OverlayImpl::print(td::StringBuilder &sb) {
diff --git a/overlay/overlays.h b/overlay/overlays.h
index c0385fc7..5eb63b13 100644
--- a/overlay/overlays.h
+++ b/overlay/overlays.h
@@ -269,6 +269,7 @@ struct OverlayOptions {
   td::uint32 nodes_to_send_ = 4;
   td::uint32 propagate_broadcast_to_ = 5;
   td::uint32 default_permanent_members_flags_ = 0;
+  double broadcast_speed_multiplier_ = 1.0;
 };
 
 class Overlays : public td::actor::Actor {
diff --git a/ton/ton-types.h b/ton/ton-types.h
index 2447a8c5..c7aff644 100644
--- a/ton/ton-types.h
+++ b/ton/ton-types.h
@@ -493,6 +493,7 @@ struct CatChainOptions {
   td::uint64 max_block_height_coeff = 0;
 
   bool debug_disable_db = false;
+  double broadcast_speed_multiplier = 1.0;
 };
 
 struct ValidatorSessionConfig {
diff --git a/validator-engine/validator-engine.cpp b/validator-engine/validator-engine.cpp
index 81b8278f..2ea04e18 100644
--- a/validator-engine/validator-engine.cpp
+++ b/validator-engine/validator-engine.cpp
@@ -1504,6 +1504,7 @@ td::Status ValidatorEngine::load_global_config() {
   }
   validator_options_.write().set_hardforks(std::move(h));
   validator_options_.write().set_fast_state_serializer_enabled(fast_state_serializer_enabled_);
+  validator_options_.write().set_catchain_broadcast_speed_multiplier(broadcast_speed_multiplier_catchain_);
 
   return td::Status::OK();
 }
@@ -2004,9 +2005,13 @@ void ValidatorEngine::start_full_node() {
       R.ensure();
       td::actor::send_closure(SelfId, &ValidatorEngine::started_full_node);
     });
+    ton::validator::fullnode::FullNodeOptions full_node_options{
+        .config_ = config_.full_node_config,
+        .public_broadcast_speed_multiplier_ = broadcast_speed_multiplier_public_,
+        .private_broadcast_speed_multiplier_ = broadcast_speed_multiplier_private_};
     full_node_ = ton::validator::fullnode::FullNode::create(
         short_id, ton::adnl::AdnlNodeIdShort{config_.full_node}, validator_options_->zero_block_id().file_hash,
-        config_.full_node_config, keyring_.get(), adnl_.get(), rldp_.get(), rldp2_.get(),
+        full_node_options, keyring_.get(), adnl_.get(), rldp_.get(), rldp2_.get(),
         default_dht_node_.is_zero() ? td::actor::ActorId<ton::dht::Dht>{} : dht_nodes_[default_dht_node_].get(),
         overlay_manager_.get(), validator_manager_.get(), full_node_client_.get(), db_root_, std::move(P));
     for (auto &v : config_.validators) {
@@ -4562,6 +4567,42 @@ int main(int argc, char *argv[]) {
       "disable persistent state serializer (similar to set-state-serializer-enabled 0 in validator console)", [&]() {
         acts.push_back([&x]() { td::actor::send_closure(x, &ValidatorEngine::set_state_serializer_disabled_flag); });
       });
+  p.add_checked_option(
+      '\0', "broadcast-speed-catchain",
+      "multiplier for broadcast speed in catchain overlays (experimental, default is 1.0, which is ~300 KB/s)",
+      [&](td::Slice s) -> td::Status {
+        auto v = td::to_double(s);
+        if (v <= 0.0) {
+          return td::Status::Error("broadcast-speed-catchain should be positive");
+        }
+        acts.push_back(
+            [&x, v]() { td::actor::send_closure(x, &ValidatorEngine::set_broadcast_speed_multiplier_catchain, v); });
+        return td::Status::OK();
+      });
+  p.add_checked_option(
+      '\0', "broadcast-speed-public",
+      "multiplier for broadcast speed in public shard overlays (experimental, default is 1.0, which is ~300 KB/s)",
+      [&](td::Slice s) -> td::Status {
+        auto v = td::to_double(s);
+        if (v <= 0.0) {
+          return td::Status::Error("broadcast-speed-public should be positive");
+        }
+        acts.push_back(
+            [&x, v]() { td::actor::send_closure(x, &ValidatorEngine::set_broadcast_speed_multiplier_public, v); });
+        return td::Status::OK();
+      });
+  p.add_checked_option(
+      '\0', "broadcast-speed-private",
+      "multiplier for broadcast speed in private block overlays (experimental, default is 1.0, which is ~300 KB/s)",
+      [&](td::Slice s) -> td::Status {
+        auto v = td::to_double(s);
+        if (v <= 0.0) {
+          return td::Status::Error("broadcast-speed-private should be positive");
+        }
+        acts.push_back(
+            [&x, v]() { td::actor::send_closure(x, &ValidatorEngine::set_broadcast_speed_multiplier_private, v); });
+        return td::Status::OK();
+      });
   auto S = p.run(argc, argv);
   if (S.is_error()) {
     LOG(ERROR) << "failed to parse options: " << S.move_as_error();
diff --git a/validator-engine/validator-engine.hpp b/validator-engine/validator-engine.hpp
index 6c2f5c4b..e0dc91f1 100644
--- a/validator-engine/validator-engine.hpp
+++ b/validator-engine/validator-engine.hpp
@@ -229,6 +229,9 @@ class ValidatorEngine : public td::actor::Actor {
   bool not_all_shards_ = false;
   std::vector<ton::ShardIdFull> add_shard_cmds_;
   bool state_serializer_disabled_flag_ = false;
+  double broadcast_speed_multiplier_catchain_ = 1.0;
+  double broadcast_speed_multiplier_public_ = 1.0;
+  double broadcast_speed_multiplier_private_ = 1.0;
 
   std::set<ton::CatchainSeqno> unsafe_catchains_;
   std::map<ton::BlockSeqno, std::pair<ton::CatchainSeqno, td::uint32>> unsafe_catchain_rotations_;
@@ -329,6 +332,15 @@ class ValidatorEngine : public td::actor::Actor {
   void set_state_serializer_disabled_flag() {
     state_serializer_disabled_flag_ = true;
   }
+  void set_broadcast_speed_multiplier_catchain(double value) {
+    broadcast_speed_multiplier_catchain_ = value;
+  }
+  void set_broadcast_speed_multiplier_public(double value) {
+    broadcast_speed_multiplier_public_ = value;
+  }
+  void set_broadcast_speed_multiplier_private(double value) {
+    broadcast_speed_multiplier_private_ = value;
+  }
 
   void start_up() override;
   ValidatorEngine() {
diff --git a/validator/full-node-private-overlay.cpp b/validator/full-node-private-overlay.cpp
index 1acfbd4e..f86323fc 100644
--- a/validator/full-node-private-overlay.cpp
+++ b/validator/full-node-private-overlay.cpp
@@ -264,8 +264,11 @@ void FullNodePrivateBlockOverlay::init() {
   overlay::OverlayPrivacyRules rules{overlay::Overlays::max_fec_broadcast_size(),
                                      overlay::CertificateFlags::AllowFec | overlay::CertificateFlags::Trusted,
                                      {}};
-  td::actor::send_closure(overlays_, &overlay::Overlays::create_private_overlay, local_id_, overlay_id_full_.clone(),
-                          nodes_, std::make_unique<Callback>(actor_id(this)), rules, R"({ "type": "private-blocks" })");
+  overlay::OverlayOptions overlay_options;
+  overlay_options.broadcast_speed_multiplier_ = opts_.private_broadcast_speed_multiplier_;
+  td::actor::send_closure(overlays_, &overlay::Overlays::create_private_overlay_ex, local_id_, overlay_id_full_.clone(),
+                          nodes_, std::make_unique<Callback>(actor_id(this)), rules, R"({ "type": "private-blocks" })",
+                          overlay_options);
 
   td::actor::send_closure(rldp_, &rldp::Rldp::add_id, local_id_);
   td::actor::send_closure(rldp2_, &rldp2::Rldp::add_id, local_id_);
@@ -366,7 +369,7 @@ void FullNodeCustomOverlay::receive_broadcast(PublicKeyHash src, td::BufferSlice
 }
 
 void FullNodeCustomOverlay::send_external_message(td::BufferSlice data) {
-  if (!inited_ || config_.ext_messages_broadcast_disabled_) {
+  if (!inited_ || opts_.config_.ext_messages_broadcast_disabled_) {
     return;
   }
   VLOG(FULL_NODE_DEBUG) << "Sending external message to custom overlay \"" << name_ << "\"";
@@ -472,10 +475,13 @@ void FullNodeCustomOverlay::init() {
     authorized_keys[sender.pubkey_hash()] = overlay::Overlays::max_fec_broadcast_size();
   }
   overlay::OverlayPrivacyRules rules{overlay::Overlays::max_fec_broadcast_size(), 0, std::move(authorized_keys)};
+  overlay::OverlayOptions overlay_options;
+  overlay_options.broadcast_speed_multiplier_ = opts_.private_broadcast_speed_multiplier_;
   td::actor::send_closure(
-      overlays_, &overlay::Overlays::create_private_overlay, local_id_, overlay_id_full_.clone(), nodes_,
+      overlays_, &overlay::Overlays::create_private_overlay_ex, local_id_, overlay_id_full_.clone(), nodes_,
       std::make_unique<Callback>(actor_id(this)), rules,
-      PSTRING() << R"({ "type": "custom-overlay", "name": ")" << td::format::Escaped{name_} << R"(" })");
+      PSTRING() << R"({ "type": "custom-overlay", "name": ")" << td::format::Escaped{name_} << R"(" })",
+      overlay_options);
 
   td::actor::send_closure(rldp_, &rldp::Rldp::add_id, local_id_);
   td::actor::send_closure(rldp2_, &rldp2::Rldp::add_id, local_id_);
diff --git a/validator/full-node-private-overlay.hpp b/validator/full-node-private-overlay.hpp
index 1e29f8c9..70e196ea 100644
--- a/validator/full-node-private-overlay.hpp
+++ b/validator/full-node-private-overlay.hpp
@@ -50,14 +50,14 @@ class FullNodePrivateBlockOverlay : public td::actor::Actor {
   void collect_validator_telemetry(std::string filename);
 
   void set_config(FullNodeConfig config) {
-    config_ = std::move(config);
+    opts_.config_ = std::move(config);
   }
 
   void start_up() override;
   void tear_down() override;
 
   FullNodePrivateBlockOverlay(adnl::AdnlNodeIdShort local_id, std::vector<adnl::AdnlNodeIdShort> nodes,
-                              FileHash zero_state_file_hash, FullNodeConfig config,
+                              FileHash zero_state_file_hash, FullNodeOptions opts,
                               td::actor::ActorId<keyring::Keyring> keyring, td::actor::ActorId<adnl::Adnl> adnl,
                               td::actor::ActorId<rldp::Rldp> rldp, td::actor::ActorId<rldp2::Rldp> rldp2,
                               td::actor::ActorId<overlay::Overlays> overlays,
@@ -66,7 +66,7 @@ class FullNodePrivateBlockOverlay : public td::actor::Actor {
       : local_id_(local_id)
       , nodes_(std::move(nodes))
       , zero_state_file_hash_(zero_state_file_hash)
-      , config_(config)
+      , opts_(opts)
       , keyring_(keyring)
       , adnl_(adnl)
       , rldp_(rldp)
@@ -80,7 +80,7 @@ class FullNodePrivateBlockOverlay : public td::actor::Actor {
   adnl::AdnlNodeIdShort local_id_;
   std::vector<adnl::AdnlNodeIdShort> nodes_;
   FileHash zero_state_file_hash_;
-  FullNodeConfig config_;
+  FullNodeOptions opts_;
   bool enable_compression_ = true;
 
   td::actor::ActorId<keyring::Keyring> keyring_;
@@ -126,14 +126,14 @@ class FullNodeCustomOverlay : public td::actor::Actor {
                             td::BufferSlice data);
 
   void set_config(FullNodeConfig config) {
-    config_ = std::move(config);
+    opts_.config_ = std::move(config);
   }
 
   void start_up() override;
   void tear_down() override;
 
   FullNodeCustomOverlay(adnl::AdnlNodeIdShort local_id, CustomOverlayParams params, FileHash zero_state_file_hash,
-                        FullNodeConfig config, td::actor::ActorId<keyring::Keyring> keyring,
+                        FullNodeOptions opts, td::actor::ActorId<keyring::Keyring> keyring,
                         td::actor::ActorId<adnl::Adnl> adnl, td::actor::ActorId<rldp::Rldp> rldp,
                         td::actor::ActorId<rldp2::Rldp> rldp2, td::actor::ActorId<overlay::Overlays> overlays,
                         td::actor::ActorId<ValidatorManagerInterface> validator_manager,
@@ -144,7 +144,7 @@ class FullNodeCustomOverlay : public td::actor::Actor {
       , msg_senders_(std::move(params.msg_senders_))
       , block_senders_(std::move(params.block_senders_))
       , zero_state_file_hash_(zero_state_file_hash)
-      , config_(config)
+      , opts_(opts)
       , keyring_(keyring)
       , adnl_(adnl)
       , rldp_(rldp)
@@ -161,7 +161,7 @@ class FullNodeCustomOverlay : public td::actor::Actor {
   std::map<adnl::AdnlNodeIdShort, int> msg_senders_;
   std::set<adnl::AdnlNodeIdShort> block_senders_;
   FileHash zero_state_file_hash_;
-  FullNodeConfig config_;
+  FullNodeOptions opts_;
 
   td::actor::ActorId<keyring::Keyring> keyring_;
   td::actor::ActorId<adnl::Adnl> adnl_;
diff --git a/validator/full-node-shard.cpp b/validator/full-node-shard.cpp
index 7d33a195..ac0eb768 100644
--- a/validator/full-node-shard.cpp
+++ b/validator/full-node-shard.cpp
@@ -105,6 +105,7 @@ void FullNodeShardImpl::create_overlay() {
   };
   overlay::OverlayOptions opts;
   opts.announce_self_ = active_;
+  opts.broadcast_speed_multiplier_ = opts_.public_broadcast_speed_multiplier_;
   td::actor::send_closure(overlays_, &overlay::Overlays::create_public_overlay_ex, adnl_id_, overlay_id_full_.clone(),
                           std::make_unique<Callback>(actor_id(this)), rules_,
                           PSTRING() << "{ \"type\": \"shard\", \"shard_id\": " << get_shard()
@@ -132,7 +133,7 @@ void FullNodeShardImpl::check_broadcast(PublicKeyHash src, td::BufferSlice broad
   if (!processed_ext_msg_broadcasts_.insert(hash).second) {
     return promise.set_error(td::Status::Error("duplicate external message broadcast"));
   }
-  if (config_.ext_messages_broadcast_disabled_) {
+  if (opts_.config_.ext_messages_broadcast_disabled_) {
     promise.set_error(td::Status::Error("rebroadcasting external messages is disabled"));
     promise = [manager = validator_manager_, message = q->message_->data_.clone()](td::Result<td::Unit> R) mutable {
       if (R.is_ok()) {
@@ -850,7 +851,7 @@ void FullNodeShardImpl::send_ihr_message(td::BufferSlice data) {
 }
 
 void FullNodeShardImpl::send_external_message(td::BufferSlice data) {
-  if (config_.ext_messages_broadcast_disabled_) {
+  if (opts_.config_.ext_messages_broadcast_disabled_) {
     return;
   }
   if (!client_.empty()) {
@@ -1367,7 +1368,7 @@ void FullNodeShardImpl::get_stats_extra(td::Promise<std::string> promise) {
 }
 
 FullNodeShardImpl::FullNodeShardImpl(ShardIdFull shard, PublicKeyHash local_id, adnl::AdnlNodeIdShort adnl_id,
-                                     FileHash zero_state_file_hash, FullNodeConfig config,
+                                     FileHash zero_state_file_hash, FullNodeOptions opts,
                                      td::actor::ActorId<keyring::Keyring> keyring, td::actor::ActorId<adnl::Adnl> adnl,
                                      td::actor::ActorId<rldp::Rldp> rldp, td::actor::ActorId<rldp2::Rldp> rldp2,
                                      td::actor::ActorId<overlay::Overlays> overlays,
@@ -1387,17 +1388,17 @@ FullNodeShardImpl::FullNodeShardImpl(ShardIdFull shard, PublicKeyHash local_id,
     , client_(client)
     , full_node_(full_node)
     , active_(active)
-    , config_(config) {
+    , opts_(opts) {
 }
 
 td::actor::ActorOwn<FullNodeShard> FullNodeShard::create(
     ShardIdFull shard, PublicKeyHash local_id, adnl::AdnlNodeIdShort adnl_id, FileHash zero_state_file_hash,
-    FullNodeConfig config, td::actor::ActorId<keyring::Keyring> keyring, td::actor::ActorId<adnl::Adnl> adnl,
+    FullNodeOptions opts, td::actor::ActorId<keyring::Keyring> keyring, td::actor::ActorId<adnl::Adnl> adnl,
     td::actor::ActorId<rldp::Rldp> rldp, td::actor::ActorId<rldp2::Rldp> rldp2,
     td::actor::ActorId<overlay::Overlays> overlays, td::actor::ActorId<ValidatorManagerInterface> validator_manager,
     td::actor::ActorId<adnl::AdnlExtClient> client, td::actor::ActorId<FullNode> full_node, bool active) {
   return td::actor::create_actor<FullNodeShardImpl>(PSTRING() << "tonnode" << shard.to_str(), shard, local_id, adnl_id,
-                                                    zero_state_file_hash, config, keyring, adnl, rldp, rldp2, overlays,
+                                                    zero_state_file_hash, opts, keyring, adnl, rldp, rldp2, overlays,
                                                     validator_manager, client, full_node, active);
 }
 
diff --git a/validator/full-node-shard.h b/validator/full-node-shard.h
index 16945325..5898db80 100644
--- a/validator/full-node-shard.h
+++ b/validator/full-node-shard.h
@@ -76,7 +76,7 @@ class FullNodeShard : public td::actor::Actor {
 
   static td::actor::ActorOwn<FullNodeShard> create(
       ShardIdFull shard, PublicKeyHash local_id, adnl::AdnlNodeIdShort adnl_id, FileHash zero_state_file_hash,
-      FullNodeConfig config, td::actor::ActorId<keyring::Keyring> keyring, td::actor::ActorId<adnl::Adnl> adnl,
+      FullNodeOptions opts, td::actor::ActorId<keyring::Keyring> keyring, td::actor::ActorId<adnl::Adnl> adnl,
       td::actor::ActorId<rldp::Rldp> rldp, td::actor::ActorId<rldp2::Rldp> rldp2,
       td::actor::ActorId<overlay::Overlays> overlays, td::actor::ActorId<ValidatorManagerInterface> validator_manager,
       td::actor::ActorId<adnl::AdnlExtClient> client, td::actor::ActorId<FullNode> full_node, bool active);
diff --git a/validator/full-node-shard.hpp b/validator/full-node-shard.hpp
index 86748134..fb3eef76 100644
--- a/validator/full-node-shard.hpp
+++ b/validator/full-node-shard.hpp
@@ -86,7 +86,7 @@ class FullNodeShardImpl : public FullNodeShard {
   void set_active(bool active) override;
 
   void set_config(FullNodeConfig config) override {
-    config_ = config;
+    opts_.config_ = config;
   }
 
   void try_get_next_block(td::Timestamp timestamp, td::Promise<ReceivedBlock> promise);
@@ -222,7 +222,7 @@ class FullNodeShardImpl : public FullNodeShard {
   }
 
   FullNodeShardImpl(ShardIdFull shard, PublicKeyHash local_id, adnl::AdnlNodeIdShort adnl_id,
-                    FileHash zero_state_file_hash, FullNodeConfig config, td::actor::ActorId<keyring::Keyring> keyring,
+                    FileHash zero_state_file_hash, FullNodeOptions opts, td::actor::ActorId<keyring::Keyring> keyring,
                     td::actor::ActorId<adnl::Adnl> adnl, td::actor::ActorId<rldp::Rldp> rldp,
                     td::actor::ActorId<rldp2::Rldp> rldp2, td::actor::ActorId<overlay::Overlays> overlays,
                     td::actor::ActorId<ValidatorManagerInterface> validator_manager,
@@ -269,7 +269,7 @@ class FullNodeShardImpl : public FullNodeShard {
 
   bool active_;
 
-  FullNodeConfig config_;
+  FullNodeOptions opts_;
 
   std::set<td::Bits256> my_ext_msg_broadcasts_;
   std::set<td::Bits256> processed_ext_msg_broadcasts_;
diff --git a/validator/full-node.cpp b/validator/full-node.cpp
index 658cb34e..e1951c36 100644
--- a/validator/full-node.cpp
+++ b/validator/full-node.cpp
@@ -139,7 +139,7 @@ void FullNodeImpl::update_adnl_id(adnl::AdnlNodeIdShort adnl_id, td::Promise<td:
 }
 
 void FullNodeImpl::set_config(FullNodeConfig config) {
-  config_ = config;
+  opts_.config_ = config;
   for (auto& s : shards_) {
     if (!s.second.actor.empty()) {
       td::actor::send_closure(s.second.actor, &FullNodeShard::set_config, config);
@@ -256,7 +256,7 @@ void FullNodeImpl::on_new_masterchain_block(td::Ref<MasterchainState> state, std
 void FullNodeImpl::update_shard_actor(ShardIdFull shard, bool active) {
   ShardInfo &info = shards_[shard];
   if (info.actor.empty()) {
-    info.actor = FullNodeShard::create(shard, local_id_, adnl_id_, zero_state_file_hash_, config_, keyring_, adnl_, rldp_,
+    info.actor = FullNodeShard::create(shard, local_id_, adnl_id_, zero_state_file_hash_, opts_, keyring_, adnl_, rldp_,
                                        rldp2_, overlays_, validator_manager_, client_, actor_id(this), active);
     if (!all_validators_.empty()) {
       td::actor::send_closure(info.actor, &FullNodeShard::update_validators, all_validators_, sign_cert_by_);
@@ -717,7 +717,7 @@ void FullNodeImpl::create_private_block_overlay(PublicKeyHash key) {
       nodes.push_back(p.second);
     }
     private_block_overlays_[key] = td::actor::create_actor<FullNodePrivateBlockOverlay>(
-        "BlocksPrivateOverlay", current_validators_[key], std::move(nodes), zero_state_file_hash_, config_, keyring_,
+        "BlocksPrivateOverlay", current_validators_[key], std::move(nodes), zero_state_file_hash_, opts_, keyring_,
         adnl_, rldp_, rldp2_, overlays_, validator_manager_, actor_id(this));
     update_validator_telemetry_collector();
   }
@@ -735,7 +735,7 @@ void FullNodeImpl::update_custom_overlay(CustomOverlayInfo &overlay) {
         old_actors.erase(it);
       } else {
         overlay.actors_[local_id] = td::actor::create_actor<FullNodeCustomOverlay>(
-            "CustomOverlay", local_id, params, zero_state_file_hash_, config_, keyring_, adnl_, rldp_, rldp2_,
+            "CustomOverlay", local_id, params, zero_state_file_hash_, opts_, keyring_, adnl_, rldp_, rldp2_,
             overlays_, validator_manager_, actor_id(this));
       }
     }
@@ -794,7 +794,7 @@ void FullNodeImpl::send_block_candidate_broadcast_to_custom_overlays(const Block
 }
 
 FullNodeImpl::FullNodeImpl(PublicKeyHash local_id, adnl::AdnlNodeIdShort adnl_id, FileHash zero_state_file_hash,
-                           FullNodeConfig config, td::actor::ActorId<keyring::Keyring> keyring,
+                           FullNodeOptions opts, td::actor::ActorId<keyring::Keyring> keyring,
                            td::actor::ActorId<adnl::Adnl> adnl, td::actor::ActorId<rldp::Rldp> rldp,
                            td::actor::ActorId<rldp2::Rldp> rldp2, td::actor::ActorId<dht::Dht> dht,
                            td::actor::ActorId<overlay::Overlays> overlays,
@@ -814,16 +814,16 @@ FullNodeImpl::FullNodeImpl(PublicKeyHash local_id, adnl::AdnlNodeIdShort adnl_id
     , client_(client)
     , db_root_(db_root)
     , started_promise_(std::move(started_promise))
-    , config_(config) {
+    , opts_(opts) {
 }
 
 td::actor::ActorOwn<FullNode> FullNode::create(
-    ton::PublicKeyHash local_id, adnl::AdnlNodeIdShort adnl_id, FileHash zero_state_file_hash, FullNodeConfig config,
+    ton::PublicKeyHash local_id, adnl::AdnlNodeIdShort adnl_id, FileHash zero_state_file_hash, FullNodeOptions opts,
     td::actor::ActorId<keyring::Keyring> keyring, td::actor::ActorId<adnl::Adnl> adnl,
     td::actor::ActorId<rldp::Rldp> rldp, td::actor::ActorId<rldp2::Rldp> rldp2, td::actor::ActorId<dht::Dht> dht,
     td::actor::ActorId<overlay::Overlays> overlays, td::actor::ActorId<ValidatorManagerInterface> validator_manager,
     td::actor::ActorId<adnl::AdnlExtClient> client, std::string db_root, td::Promise<td::Unit> started_promise) {
-  return td::actor::create_actor<FullNodeImpl>("fullnode", local_id, adnl_id, zero_state_file_hash, config, keyring,
+  return td::actor::create_actor<FullNodeImpl>("fullnode", local_id, adnl_id, zero_state_file_hash, opts, keyring,
                                                adnl, rldp, rldp2, dht, overlays, validator_manager, client, db_root,
                                                std::move(started_promise));
 }
diff --git a/validator/full-node.h b/validator/full-node.h
index fdb1bf3b..555082dc 100644
--- a/validator/full-node.h
+++ b/validator/full-node.h
@@ -55,6 +55,12 @@ struct FullNodeConfig {
   bool ext_messages_broadcast_disabled_ = false;
 };
 
+struct FullNodeOptions {
+  FullNodeConfig config_;
+  double public_broadcast_speed_multiplier_ = 1.0;
+  double private_broadcast_speed_multiplier_ = 1.0;
+};
+
 struct CustomOverlayParams {
   std::string name_;
   std::vector<adnl::AdnlNodeIdShort> nodes_;
@@ -107,7 +113,7 @@ class FullNode : public td::actor::Actor {
   enum { broadcast_mode_public = 1, broadcast_mode_private_block = 2, broadcast_mode_custom = 4 };
 
   static td::actor::ActorOwn<FullNode> create(
-      ton::PublicKeyHash local_id, adnl::AdnlNodeIdShort adnl_id, FileHash zero_state_file_hash, FullNodeConfig config,
+      ton::PublicKeyHash local_id, adnl::AdnlNodeIdShort adnl_id, FileHash zero_state_file_hash, FullNodeOptions opts,
       td::actor::ActorId<keyring::Keyring> keyring, td::actor::ActorId<adnl::Adnl> adnl,
       td::actor::ActorId<rldp::Rldp> rldp, td::actor::ActorId<rldp2::Rldp> rldp2, td::actor::ActorId<dht::Dht> dht,
       td::actor::ActorId<overlay::Overlays> overlays, td::actor::ActorId<ValidatorManagerInterface> validator_manager,
diff --git a/validator/full-node.hpp b/validator/full-node.hpp
index 0ea6fa0b..b4c79363 100644
--- a/validator/full-node.hpp
+++ b/validator/full-node.hpp
@@ -98,7 +98,7 @@ class FullNodeImpl : public FullNode {
   void start_up() override;
 
   FullNodeImpl(PublicKeyHash local_id, adnl::AdnlNodeIdShort adnl_id, FileHash zero_state_file_hash,
-               FullNodeConfig config, td::actor::ActorId<keyring::Keyring> keyring, td::actor::ActorId<adnl::Adnl> adnl,
+               FullNodeOptions opts, td::actor::ActorId<keyring::Keyring> keyring, td::actor::ActorId<adnl::Adnl> adnl,
                td::actor::ActorId<rldp::Rldp> rldp, td::actor::ActorId<rldp2::Rldp> rldp2,
                td::actor::ActorId<dht::Dht> dht, td::actor::ActorId<overlay::Overlays> overlays,
                td::actor::ActorId<ValidatorManagerInterface> validator_manager,
@@ -141,7 +141,7 @@ class FullNodeImpl : public FullNode {
   std::set<PublicKeyHash> local_keys_;
 
   td::Promise<td::Unit> started_promise_;
-  FullNodeConfig config_;
+  FullNodeOptions opts_;
 
   std::map<PublicKeyHash, td::actor::ActorOwn<FullNodePrivateBlockOverlay>> private_block_overlays_;
   bool broadcast_block_candidates_in_public_overlay_ = false;
diff --git a/validator/validator-group.cpp b/validator/validator-group.cpp
index 1817180d..110ccd81 100644
--- a/validator/validator-group.cpp
+++ b/validator/validator-group.cpp
@@ -373,6 +373,7 @@ void ValidatorGroup::create_session() {
   }
   CHECK(found);
 
+  config_.catchain_opts.broadcast_speed_multiplier = opts_->get_catchain_broadcast_speed_multiplier();
   if (!config_.new_catchain_ids) {
     session_ = validatorsession::ValidatorSession::create(session_id_, config_, local_id_, std::move(vec),
                                                           make_validator_session_callback(), keyring_, adnl_, rldp_,
diff --git a/validator/validator-options.hpp b/validator/validator-options.hpp
index e958d886..ace6b106 100644
--- a/validator/validator-options.hpp
+++ b/validator/validator-options.hpp
@@ -154,6 +154,9 @@ struct ValidatorManagerOptionsImpl : public ValidatorManagerOptions {
   bool get_fast_state_serializer_enabled() const override {
     return fast_state_serializer_enabled_;
   }
+  double get_catchain_broadcast_speed_multiplier() const override {
+    return catchain_broadcast_speed_multipliers_;
+  }
 
   void set_zero_block_id(BlockIdExt block_id) override {
     zero_block_id_ = block_id;
@@ -249,6 +252,9 @@ struct ValidatorManagerOptionsImpl : public ValidatorManagerOptions {
   void set_fast_state_serializer_enabled(bool value) override {
     fast_state_serializer_enabled_ = value;
   }
+  void set_catchain_broadcast_speed_multiplier(double value) override {
+    catchain_broadcast_speed_multipliers_ = value;
+  }
 
   ValidatorManagerOptionsImpl *make_copy() const override {
     return new ValidatorManagerOptionsImpl(*this);
@@ -302,6 +308,7 @@ struct ValidatorManagerOptionsImpl : public ValidatorManagerOptions {
   bool state_serializer_enabled_ = true;
   td::Ref<CollatorOptions> collator_options_{true};
   bool fast_state_serializer_enabled_ = false;
+  double catchain_broadcast_speed_multipliers_;
 };
 
 }  // namespace validator
diff --git a/validator/validator.h b/validator/validator.h
index 42b3f69a..5d6c0173 100644
--- a/validator/validator.h
+++ b/validator/validator.h
@@ -116,6 +116,7 @@ struct ValidatorManagerOptions : public td::CntObject {
   virtual bool get_state_serializer_enabled() const = 0;
   virtual td::Ref<CollatorOptions> get_collator_options() const = 0;
   virtual bool get_fast_state_serializer_enabled() const = 0;
+  virtual double get_catchain_broadcast_speed_multiplier() const = 0;
 
   virtual void set_zero_block_id(BlockIdExt block_id) = 0;
   virtual void set_init_block_id(BlockIdExt block_id) = 0;
@@ -148,6 +149,7 @@ struct ValidatorManagerOptions : public td::CntObject {
   virtual void set_state_serializer_enabled(bool value) = 0;
   virtual void set_collator_options(td::Ref<CollatorOptions> value) = 0;
   virtual void set_fast_state_serializer_enabled(bool value) = 0;
+  virtual void set_catchain_broadcast_speed_multiplier(double value) = 0;
 
   static td::Ref<ValidatorManagerOptions> create(
       BlockIdExt zero_block_id, BlockIdExt init_block_id,