feat: boostrap hicn 22.02

The current patch provides several new features, improvements,
bug fixes and also complete rewrite of entire components.

- lib
The hicn packet parser has been improved with a new packet
format fully based on UDP. The TCP header is still temporarily
supported but the UDP header will replace completely the new hicn
packet format. Improvements have been made to make sure every
packet parsing operation is made via this library. The current
new header can be used as header between the payload and the
UDP header or as trailer in the UDP surplus area to be tested
when UDP options will start to be used.

- hicn-light
The portable packet forwarder has been completely rewritten from
scratch with the twofold objective to improve performance and
code size but  also to drop dependencies such as libparc which is
now removed by the current implementation.

- hicn control
the control library is the agent that is used to program the
packet forwarders via their binary API. This component has
benefited from significant improvements in terms of interaction
model which is now event driven and more robust to failures.

- VPP plugin has been updated to support VPP 22.02

- transport
Major improvement have been made to the RTC protocol, to the
support of IO modules and to the security sub system. Signed
manifests are the default data authenticity and integrity framework.
Confidentiality can be enabled by sharing the encryption key to the
prod/cons layer. The library has been tested with group key based
applications such as broadcast/multicast and real-time on-line
meetings with trusted server keys or MLS.

- testing
Unit testing has been introduced using GoogleTest. One third of
the code base is covered by unit testing with priority on
critical features. Functional testing has also been introduce
using Docker, linux bridging and Robot Framework to define
test with Less Code techniques to facilitate the extension
of the coverage.

Co-authored-by: Mauro Sardara <msardara@cisco.com>
Co-authored-by: Jordan Augé <jordan.auge+fdio@cisco.com>
Co-authored-by: Michele Papalini <micpapal@cisco.com>
Co-authored-by: Angelo Mantellini <manangel@cisco.com>
Co-authored-by: Jacques Samain <jsamain@cisco.com>
Co-authored-by: Olivier Roques <oroques+fdio@cisco.com>
Co-authored-by: Enrico Loparco <eloparco@cisco.com>
Co-authored-by: Giulio Grassi <gigrassi@cisco.com>

Change-Id: I75d0ef70f86d921e3ef503c99271216ff583c215
Signed-off-by: Luca Muscariello <muscariello@ieee.org>
Signed-off-by: Mauro Sardara <msardara@cisco.com>

1 files changed, 434 insertions, 119 deletions

diff --git a/libtransport/src/protocols/prod_protocol_rtc.cc b/libtransport/src/protocols/prod_protocol_rtc.cc
index cdc882d81..242abd30d 100644
--- a/libtransport/src/protocols/prod_protocol_rtc.cc
+++ b/libtransport/src/protocols/prod_protocol_rtc.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017-2019 Cisco and/or its affiliates.
+ * Copyright (c) 2021 Cisco and/or its affiliates.
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
@@ -13,9 +13,11 @@
  * limitations under the License.
  */
 
+#include <glog/logging.h>
 #include <hicn/transport/core/global_object_pool.h>
 #include <implementation/socket_producer.h>
 #include <protocols/prod_protocol_rtc.h>
+#include <protocols/rtc/probe_handler.h>
 #include <protocols/rtc/rtc_consts.h>
 #include <stdlib.h>
 #include <time.h>
@@ -38,71 +40,89 @@ RTCProductionProtocol::RTCProductionProtocol(
       bytes_production_rate_(0),
       packets_production_rate_(0),
       fec_packets_production_rate_(0),
-      last_round_(std::chrono::duration_cast<std::chrono::milliseconds>(
-                      std::chrono::steady_clock::now().time_since_epoch())
-                      .count()),
+      last_produced_data_ts_(0),
+      last_round_(utils::SteadyTime::nowMs().count()),
       allow_delayed_nacks_(false),
       queue_timer_on_(false),
       consumer_in_sync_(false),
-      on_consumer_in_sync_(nullptr) {
-  srand((unsigned int)time(NULL));
-  prod_label_ = rand() % 256;
+      on_consumer_in_sync_(nullptr),
+      pending_fec_pace_(false),
+      max_len_(0),
+      queue_len_(0),
+      data_aggregation_(true),
+      data_aggregation_timer_switch_(false) {
+  std::uniform_int_distribution<> dis(0, 255);
+  prod_label_ = dis(gen_);
   cache_label_ = (prod_label_ + 1) % 256;
   interests_queue_timer_ =
-      std::make_unique<asio::steady_timer>(portal_->getIoService());
-  round_timer_ = std::make_unique<asio::steady_timer>(portal_->getIoService());
+      std::make_unique<asio::steady_timer>(portal_->getThread().getIoService());
+  round_timer_ =
+      std::make_unique<asio::steady_timer>(portal_->getThread().getIoService());
+  fec_pacing_timer_ =
+      std::make_unique<asio::steady_timer>(portal_->getThread().getIoService());
+  app_packets_timer_ =
+      std::make_unique<asio::steady_timer>(portal_->getThread().getIoService());
   setOutputBufferSize(10000);
-  scheduleRoundTimer();
+}
+
+RTCProductionProtocol::~RTCProductionProtocol() {}
+
+void RTCProductionProtocol::setProducerParam() {
+  // Flow name: here we assume there is only one prefix registered in the portal
+  flow_name_ = portal_->getServedNamespaces().begin()->getName();
+
+  // Manifest
+  uint32_t making_manifest;
+  socket_->getSocketOption(interface::GeneralTransportOptions::MAKE_MANIFEST,
+                           making_manifest);
+
+  // Signer
+  std::shared_ptr<auth::Signer> signer;
+  socket_->getSocketOption(interface::GeneralTransportOptions::SIGNER, signer);
+
+  // Default format
+  core::Packet::Format default_format;
+  socket_->getSocketOption(interface::GeneralTransportOptions::PACKET_FORMAT,
+                           default_format);
 
   // FEC
   using namespace std::placeholders;
   enableFEC(std::bind(&RTCProductionProtocol::onFecPackets, this, _1),
             std::bind(&RTCProductionProtocol::getBuffer, this, _1));
-}
 
-RTCProductionProtocol::~RTCProductionProtocol() {}
+  // Aggregated data
+  socket_->getSocketOption(interface::RtcTransportOptions::AGGREGATED_DATA,
+                           data_aggregation_);
 
-void RTCProductionProtocol::registerNamespaceWithNetwork(
-    const Prefix &producer_namespace) {
-  ProductionProtocol::registerNamespaceWithNetwork(producer_namespace);
-
-  flow_name_ = producer_namespace.getName();
-  auto family = flow_name_.getAddressFamily();
-
-  switch (family) {
-    case AF_INET6:
-      data_header_size_ =
-          signer_ && !making_manifest_
-              ? (uint32_t)Packet::getHeaderSizeFromFormat(
-                    HF_INET6_TCP_AH, signer_->getSignatureFieldSize())
-              : (uint32_t)Packet::getHeaderSizeFromFormat(HF_INET6_TCP);
-      ;
-      break;
-    case AF_INET:
-      data_header_size_ =
-          signer_ && !making_manifest_
-              ? (uint32_t)Packet::getHeaderSizeFromFormat(
-                    HF_INET_TCP_AH, signer_->getSignatureFieldSize())
-              : (uint32_t)Packet::getHeaderSizeFromFormat(HF_INET_TCP);
-      break;
-    default:
-      throw errors::RuntimeException("Unknown name format.");
-  }
+  size_t signature_size = signer->getSignatureFieldSize();
+  data_header_format_ = {
+      !making_manifest ? Packet::toAHFormat(default_format) : default_format,
+      !making_manifest ? signature_size : 0};
+  manifest_header_format_ = {Packet::toAHFormat(default_format),
+                             signature_size};
+  nack_header_format_ = {Packet::toAHFormat(default_format), signature_size};
+  fec_header_format_ = {Packet::toAHFormat(default_format), signature_size};
+
+  // Schedule round timer
+  scheduleRoundTimer();
 }
 
 void RTCProductionProtocol::scheduleRoundTimer() {
   round_timer_->expires_from_now(
       std::chrono::milliseconds(rtc::PRODUCER_STATS_INTERVAL));
-  round_timer_->async_wait([this](std::error_code ec) {
+  std::weak_ptr<RTCProductionProtocol> self = shared_from_this();
+  round_timer_->async_wait([self](const std::error_code &ec) {
     if (ec) return;
-    updateStats();
+
+    auto sp = self.lock();
+    if (sp && sp->isRunning()) {
+      sp->updateStats();
+    }
   });
 }
 
 void RTCProductionProtocol::updateStats() {
-  uint64_t now = std::chrono::duration_cast<std::chrono::milliseconds>(
-                     std::chrono::steady_clock::now().time_since_epoch())
-                     .count();
+  uint64_t now = utils::SteadyTime::nowMs().count();
   uint64_t duration = now - last_round_;
   if (duration == 0) duration = 1;
   double per_second = rtc::MILLI_IN_A_SEC / duration;
@@ -125,11 +145,12 @@ void RTCProductionProtocol::updateStats() {
   if (max_packet_production_ < rtc::WIN_MIN)
     max_packet_production_ = rtc::WIN_MIN;
 
-  if (packets_production_rate_ != 0) {
-    allow_delayed_nacks_ = false;
-  } else if (prev_packets_production_rate == 0) {
-    // at least 2 rounds with production rate = 0
+  if (packets_production_rate_ <= rtc::MIN_PRODUCTION_RATE ||
+      prev_packets_production_rate <= rtc::MIN_PRODUCTION_RATE) {
     allow_delayed_nacks_ = true;
+  } else {
+    // at least 2 rounds with enough packets
+    allow_delayed_nacks_ = false;
   }
 
   // check if the production rate is decreased. if yes send nacks if needed
@@ -170,42 +191,237 @@ uint32_t RTCProductionProtocol::produceDatagram(
   socket_->getSocketOption(interface::GeneralTransportOptions::DATA_PACKET_SIZE,
                            data_packet_size);
 
-  if (TRANSPORT_EXPECT_FALSE((buffer_size + data_header_size_ +
-                              rtc::DATA_HEADER_SIZE) > data_packet_size)) {
+  if (TRANSPORT_EXPECT_FALSE(
+          (Packet::getHeaderSizeFromFormat(data_header_format_.first,
+                                           data_header_format_.second) +
+           rtc::DATA_HEADER_SIZE + buffer_size) > data_packet_size)) {
     return 0;
   }
 
+  if (!data_aggregation_) {
+    // if data aggregation is off emptyQueue will always return doing nothing
+    emptyQueue();
+
+    sendManifest(content_name);
+
+    // create content object
+    auto content_object =
+        core::PacketManager<>::getInstance().getPacket<ContentObject>(
+            data_header_format_.first, data_header_format_.second);
+
+    // add rtc header to the payload
+    struct rtc::data_packet_t header;
+    content_object->appendPayload((const uint8_t *)&header,
+                                  rtc::DATA_HEADER_SIZE);
+    content_object->appendPayload(buffer->data(), buffer->length());
+
+    // schedule actual sending on internal thread
+    portal_->getThread().tryRunHandlerNow(
+        [this, content_object{std::move(content_object)},
+         content_name]() mutable {
+          produceInternal(std::move(content_object), content_name);
+        });
+  } else {
+    // XXX here we assume that all the packets that we push to the queue have
+    // the same name
+    auto app_pkt = utils::MemBuf::copyBuffer(buffer->data(), buffer->length());
+    addPacketToQueue(std::move(app_pkt));
+  }
+
+  return 1;
+}
+
+void RTCProductionProtocol::addPacketToQueue(
+    std::unique_ptr<utils::MemBuf> &&buffer) {
+  std::size_t buffer_size = buffer->length();
+  if ((queue_len_ + buffer_size) > rtc::MAX_RTC_PAYLOAD_SIZE) {
+    emptyQueue();  // this should guaranty that the generated packet will never
+                   // be larger than an MTU
+  }
+
+  waiting_app_packets_.push(std::move(buffer));
+  if (max_len_ < buffer_size) max_len_ = buffer_size;
+  queue_len_ += buffer_size;
+
+  if (waiting_app_packets_.size() >= rtc::MAX_AGGREGATED_PACKETS) {
+    emptyQueue();
+  }
+
+  if (waiting_app_packets_.size() >= 1 && !data_aggregation_timer_switch_) {
+    data_aggregation_timer_switch_ = true;
+    app_packets_timer_->expires_from_now(
+        std::chrono::milliseconds(rtc::AGGREGATED_PACKETS_TIMER));
+    std::weak_ptr<RTCProductionProtocol> self = shared_from_this();
+    app_packets_timer_->async_wait([self](const std::error_code &ec) {
+      if (ec) return;
+
+      auto ptr = self.lock();
+      if (ptr && ptr->isRunning()) {
+        if (!ptr->data_aggregation_timer_switch_) return;
+        ptr->emptyQueue();
+      }
+    });
+  }
+}
+
+void RTCProductionProtocol::emptyQueue() {
+  if (waiting_app_packets_.size() == 0) return;  // queue is empty
+
+  Name n(flow_name_);
+
+  // cancel timer is scheduled
+  if (data_aggregation_timer_switch_) {
+    data_aggregation_timer_switch_ = false;
+    app_packets_timer_->cancel();
+  }
+
+  // send a manifest beforehand if the hash buffer if full
+  sendManifest(n);
+
+  // create content object
   auto content_object =
       core::PacketManager<>::getInstance().getPacket<ContentObject>(
-          signer_ ? Format::HF_INET6_TCP_AH : Format::HF_INET6_TCP,
-          signer_ ? signer_->getSignatureFieldSize() : 0);
+          data_header_format_.first, data_header_format_.second);
+
   // add rtc header to the payload
   struct rtc::data_packet_t header;
   content_object->appendPayload((const uint8_t *)&header,
                                 rtc::DATA_HEADER_SIZE);
-  content_object->appendPayload(buffer->data(), buffer->length());
 
-  // schedule actual sending on internal thread
-  portal_->getIoService().dispatch([this,
-                                    content_object{std::move(content_object)},
-                                    content_name]() mutable {
-    produceInternal(std::move(content_object), content_name);
+  // init aggregated header
+  rtc::AggrPktHeader hdr(
+      (uint8_t *)(content_object->getPayload()->data() + rtc::DATA_HEADER_SIZE),
+      max_len_, waiting_app_packets_.size());
+  uint32_t header_size = hdr.getHeaderLen();
+  content_object->append(header_size);  // leave space for the aggregated header
+
+  uint8_t index = 0;
+  while (waiting_app_packets_.size() != 0) {
+    std::unique_ptr<utils::MemBuf> pkt =
+        std::move(waiting_app_packets_.front());
+    waiting_app_packets_.pop();
+    // XXX for the moment we have a single name, so this works, otherwise we
+    // need to do something else
+    hdr.addPacketToHeader(index, pkt->length());
+    // append packet
+    content_object->appendPayload(pkt->data(), pkt->length());
+    index++;
+  }
+
+  // reset queue values
+  max_len_ = 0;
+  queue_len_ = 0;
+
+  // the packet is ready we need to send it
+  portal_->getThread().tryRunHandlerNow(
+      [this, content_object{std::move(content_object)}, n]() mutable {
+        produceInternal(std::move(content_object), n);
+      });
+}
+
+void RTCProductionProtocol::sendManifest(const Name &name) {
+  if (!making_manifest_) {
+    return;
+  }
+
+  Name manifest_name(name);
+
+  uint32_t data_packet_size;
+  socket_->getSocketOption(interface::GeneralTransportOptions::DATA_PACKET_SIZE,
+                           data_packet_size);
+
+  // The maximum number of entries a manifest can hold
+  uint32_t manifest_capacity = making_manifest_;
+
+  // If there is not enough hashes to fill a manifest, return early
+  if (manifest_entries_.size() < manifest_capacity) {
+    return;
+  }
+
+  // Create a new manifest
+  std::shared_ptr<core::ContentObjectManifest> manifest =
+      createManifest(manifest_name.setSuffix(current_seg_));
+
+  // Fill the manifest with packet hashes that were previously saved
+  uint32_t nb_entries;
+  for (nb_entries = 0; nb_entries < manifest_capacity; ++nb_entries) {
+    if (manifest_entries_.empty()) {
+      break;
+    }
+    std::pair<uint32_t, auth::CryptoHash> front = manifest_entries_.front();
+    manifest->addSuffixHash(front.first, front.second);
+    manifest_entries_.pop();
+  }
+
+  DLOG_IF(INFO, VLOG_IS_ON(3))
+      << "Sending manifest " << manifest->getName().getSuffix() << " of size "
+      << nb_entries;
+
+  // Encode and send the manifest
+  manifest->encode();
+  portal_->getThread().tryRunHandlerNow(
+      [this, content_object{std::move(manifest)}, manifest_name]() mutable {
+        produceInternal(std::move(content_object), manifest_name);
+      });
+}
+
+std::shared_ptr<core::ContentObjectManifest>
+RTCProductionProtocol::createManifest(const Name &content_name) const {
+  Name name(content_name);
+
+  auth::CryptoHashType hash_algo;
+  socket_->getSocketOption(interface::GeneralTransportOptions::HASH_ALGORITHM,
+                           hash_algo);
+
+  uint64_t now = utils::SteadyTime::nowMs().count();
+
+  // Create a new manifest
+  std::shared_ptr<core::ContentObjectManifest> manifest(
+      ContentObjectManifest::createManifest(
+          manifest_header_format_.first, name, core::ManifestVersion::VERSION_1,
+          core::ManifestType::INLINE_MANIFEST, false, name, hash_algo,
+          manifest_header_format_.second));
+
+  // Set connection parameters
+  manifest->setParamsRTC(ParamsRTC{
+      .timestamp = now,
+      .prod_rate = bytes_production_rate_,
+      .prod_seg = current_seg_,
+      .support_fec = false,
   });
 
-  return 1;
+  return manifest;
 }
 
 void RTCProductionProtocol::produceInternal(
     std::shared_ptr<ContentObject> &&content_object, const Name &content_name,
     bool fec) {
+  uint64_t now = utils::SteadyTime::nowMs().count();
+
+  if (fec && (now - last_produced_data_ts_) < rtc::FEC_PACING_TIME) {
+    paced_fec_packets_.push(std::pair<uint64_t, ContentObject::Ptr>(
+        now, std::move(content_object)));
+    postponeFecPacket();
+  } else {
+    // need to check if there are FEC packets waiting to be sent
+    flushFecPkts(current_seg_);
+    producePktInternal(std::move(content_object), content_name, fec);
+  }
+}
+
+void RTCProductionProtocol::producePktInternal(
+    std::shared_ptr<ContentObject> &&content_object, const Name &content_name,
+    bool fec) {
+  bool is_manifest = content_object->getPayloadType() == PayloadType::MANIFEST;
+  uint64_t now = utils::SteadyTime::nowMs().count();
+
   // set rtc header
-  struct rtc::data_packet_t *data_pkt =
-      (struct rtc::data_packet_t *)content_object->getPayload()->data();
-  uint64_t now = std::chrono::duration_cast<std::chrono::milliseconds>(
-                     std::chrono::steady_clock::now().time_since_epoch())
-                     .count();
-  data_pkt->setTimestamp(now);
-  data_pkt->setProductionRate(bytes_production_rate_);
+  if (!is_manifest) {
+    struct rtc::data_packet_t *data_pkt =
+        (struct rtc::data_packet_t *)content_object->getPayload()->data();
+    data_pkt->setTimestamp(now);
+    data_pkt->setProductionRate(bytes_production_rate_);
+  }
 
   // set hicn stuff
   Name n(content_name);
@@ -213,11 +429,6 @@ void RTCProductionProtocol::produceInternal(
   content_object->setLifetime(500);  // XXX this should be set by the APP
   content_object->setPathLabel(prod_label_);
 
-  // sign packet
-  if (signer_) {
-    signer_->signPacket(content_object.get());
-  }
-
   // update stats
   if (!fec) {
     produced_bytes_ +=
@@ -227,7 +438,7 @@ void RTCProductionProtocol::produceInternal(
     produced_fec_packets_++;
   }
 
-  if (produced_packets_ >= max_packet_production_) {
+  if (!data_aggregation_ && produced_packets_ >= max_packet_production_) {
     // in this case all the pending interests may be used to accomodate the
     // sudden increase in the production rate. calling the updateStats we will
     // notify all the clients
@@ -240,8 +451,12 @@ void RTCProductionProtocol::produceInternal(
 
   // pass packet to FEC encoder
   if (fec_encoder_ && !fec) {
-    fec_encoder_->onPacketProduced(
-        *content_object, content_object->headerSize() + rtc::DATA_HEADER_SIZE);
+    uint32_t offset =
+        is_manifest ? content_object->headerSize()
+                    : content_object->headerSize() + rtc::DATA_HEADER_SIZE;
+    uint32_t metadata = static_cast<uint32_t>(content_object->getPayloadType());
+
+    fec_encoder_->onPacketProduced(*content_object, offset, metadata);
   }
 
   output_buffer_.insert(content_object);
@@ -253,7 +468,7 @@ void RTCProductionProtocol::produceInternal(
 
   auto seq_it = seqs_map_.find(current_seg_);
   if (seq_it != seqs_map_.end()) {
-    portal_->sendContentObject(*content_object);
+    sendContentObject(content_object, false, fec);
   }
 
   if (*on_content_object_output_) {
@@ -264,6 +479,8 @@ void RTCProductionProtocol::produceInternal(
   // remove interests from the interest cache if it exists
   removeFromInterestQueue(current_seg_);
 
+  if (!fec) last_produced_data_ts_ = now;
+
   // Update current segment
   current_seg_ = (current_seg_ + 1) % rtc::MIN_PROBE_SEQ;
 
@@ -277,6 +494,55 @@ void RTCProductionProtocol::produceInternal(
   }
 }
 
+void RTCProductionProtocol::flushFecPkts(uint32_t current_seq_num) {
+  // Currently we immediately send all the pending fec packets
+  // A pacing policy may be helpful, but we do not want to delay too much
+  // the packets at this moment.
+  while (paced_fec_packets_.size() > 0) {
+    producePktInternal(std::move(paced_fec_packets_.front().second), flow_name_,
+                       true);
+    paced_fec_packets_.pop();
+  }
+  fec_pacing_timer_->cancel();
+  pending_fec_pace_ = false;
+  postponeFecPacket();
+}
+
+void RTCProductionProtocol::postponeFecPacket() {
+  if (paced_fec_packets_.size() == 0) return;
+  if (pending_fec_pace_) {
+    return;
+  }
+
+  uint64_t produced_time = paced_fec_packets_.front().first;
+  uint64_t now = utils::SteadyTime::nowMs().count();
+
+  uint64_t wait_time = 0;
+  if ((produced_time + rtc::FEC_PACING_TIME) > now)
+    wait_time = produced_time + rtc::FEC_PACING_TIME - now;
+
+  fec_pacing_timer_->expires_from_now(std::chrono::milliseconds(wait_time));
+  pending_fec_pace_ = true;
+
+  std::weak_ptr<RTCProductionProtocol> self = shared_from_this();
+  fec_pacing_timer_->async_wait([self](const std::error_code &ec) {
+    if (ec) return;
+
+    auto sp = self.lock();
+    if (sp && sp->isRunning()) {
+      if (!sp->pending_fec_pace_) return;
+
+      if (sp->paced_fec_packets_.size() > 0) {
+        sp->producePktInternal(std::move(sp->paced_fec_packets_.front().second),
+                               sp->flow_name_, true);
+        sp->paced_fec_packets_.pop();
+      }
+      sp->pending_fec_pace_ = false;
+      sp->postponeFecPacket();
+    }
+  });
+}
+
 void RTCProductionProtocol::onInterest(Interest &interest) {
   if (*on_interest_input_) {
     on_interest_input_->operator()(*socket_->getInterface(), interest);
@@ -284,7 +550,7 @@ void RTCProductionProtocol::onInterest(Interest &interest) {
 
   auto suffix = interest.firstSuffix();
   // numberOfSuffixes returns only the prefixes in the payalod
-  // we add + 1 to count anche the seq in the name
+  // we add + 1 to count also the seq in the name
   auto n_suffixes = interest.numberOfSuffixes() + 1;
   Name name = interest.getName();
   bool prev_consumer_state = consumer_in_sync_;
@@ -293,6 +559,7 @@ void RTCProductionProtocol::onInterest(Interest &interest) {
     if (i > 0) {
       name.setSuffix(*(suffix + (i - 1)));
     }
+
     DLOG_IF(INFO, VLOG_IS_ON(3)) << "Received interest " << name;
 
     const std::shared_ptr<ContentObject> content_object =
@@ -312,7 +579,7 @@ void RTCProductionProtocol::onInterest(Interest &interest) {
       DLOG_IF(INFO, VLOG_IS_ON(3))
           << "Send content %u (onInterest) " << content_object->getName();
       content_object->setPathLabel(cache_label_);
-      portal_->sendContentObject(*content_object);
+      sendContentObject(content_object);
     } else {
       if (*on_interest_process_) {
         on_interest_process_->operator()(*socket_->getInterface(), interest);
@@ -332,14 +599,19 @@ void RTCProductionProtocol::processInterest(uint32_t interest_seg,
     consumer_in_sync_ = false;
   }
 
-  uint64_t now = std::chrono::duration_cast<std::chrono::milliseconds>(
-                     std::chrono::steady_clock::now().time_since_epoch())
-                     .count();
+  uint64_t now = utils::SteadyTime::nowMs().count();
 
-  if (interest_seg > rtc::MIN_PROBE_SEQ) {
-    DLOG_IF(INFO, VLOG_IS_ON(3)) << "Received probe " << interest_seg;
-    sendNack(interest_seg);
-    return;
+  switch (rtc::ProbeHandler::getProbeType(interest_seg)) {
+    case rtc::ProbeType::INIT:
+      DLOG_IF(INFO, VLOG_IS_ON(3)) << "Received init probe " << interest_seg;
+      sendManifestProbe(interest_seg);
+      return;
+    case rtc::ProbeType::RTT:
+      DLOG_IF(INFO, VLOG_IS_ON(3)) << "Received RTT probe " << interest_seg;
+      sendNack(interest_seg);
+      return;
+    default:
+      break;
   }
 
   // if the production rate 0 use delayed nacks
@@ -349,7 +621,7 @@ void RTCProductionProtocol::processInterest(uint32_t interest_seg,
       next_timer = timers_map_.begin()->first;
     }
 
-    uint64_t expiration = now + rtc::SENTINEL_TIMER_INTERVAL;
+    uint64_t expiration = now + rtc::NACK_DELAY;
     addToInterestQueue(interest_seg, expiration);
 
     // here we have at least one interest in the queue, we need to start or
@@ -369,8 +641,8 @@ void RTCProductionProtocol::processInterest(uint32_t interest_seg,
   }
 
   if (queue_timer_on_) {
-    // the producer is producing. Send nacks to packets that will expire before
-    // the data production and remove the timer
+    // the producer is producing. Send nacks to packets that will expire
+    // before the data production and remove the timer
     queue_timer_on_ = false;
     interests_queue_timer_->cancel();
     sendNacksForPendingInterests();
@@ -387,8 +659,8 @@ void RTCProductionProtocol::processInterest(uint32_t interest_seg,
     sendNack(interest_seg);
   } else {
     if (!consumer_in_sync_ && on_consumer_in_sync_) {
-      // we consider the remote consumer to be in sync as soon as it covers 70%
-      // of the production window with interests
+      // we consider the remote consumer to be in sync as soon as it covers
+      // 70% of the production window with interests
       uint32_t perc = ceil((double)max_gap * 0.7);
       if (interest_seg > (perc + current_seg_)) {
         consumer_in_sync_ = true;
@@ -401,13 +673,18 @@ void RTCProductionProtocol::processInterest(uint32_t interest_seg,
   }
 }
 
-void RTCProductionProtocol::onError(std::error_code ec) {}
-
 void RTCProductionProtocol::scheduleQueueTimer(uint64_t wait) {
   interests_queue_timer_->expires_from_now(std::chrono::milliseconds(wait));
-  interests_queue_timer_->async_wait([this](std::error_code ec) {
-    if (ec) return;
-    interestQueueTimer();
+  std::weak_ptr<RTCProductionProtocol> self = shared_from_this();
+  interests_queue_timer_->async_wait([self](const std::error_code &ec) {
+    if (ec) {
+      return;
+    }
+
+    auto sp = self.lock();
+    if (sp && sp->isRunning()) {
+      sp->interestQueueTimer();
+    }
   });
 }
 
@@ -450,9 +727,7 @@ void RTCProductionProtocol::sendNacksForPendingInterests() {
   if (packets_production_rate_ != 0)
     packet_gap = ceil(rtc::MILLI_IN_A_SEC / (double)packets_production_rate_);
 
-  uint64_t now = std::chrono::duration_cast<std::chrono::milliseconds>(
-                     std::chrono::steady_clock::now().time_since_epoch())
-                     .count();
+  uint64_t now = utils::SteadyTime::nowMs().count();
 
   for (auto it = seqs_map_.begin(); it != seqs_map_.end(); it++) {
     if (it->first > current_seg_) {
@@ -486,9 +761,7 @@ void RTCProductionProtocol::removeFromInterestQueue(uint32_t interest_seg) {
 }
 
 void RTCProductionProtocol::interestQueueTimer() {
-  uint64_t now = std::chrono::duration_cast<std::chrono::milliseconds>(
-                     std::chrono::steady_clock::now().time_since_epoch())
-                     .count();
+  uint64_t now = utils::SteadyTime::nowMs().count();
 
   for (auto it_timers = timers_map_.begin(); it_timers != timers_map_.end();) {
     uint64_t expire = it_timers->first;
@@ -511,20 +784,37 @@ void RTCProductionProtocol::interestQueueTimer() {
   }
 }
 
+void RTCProductionProtocol::sendManifestProbe(uint32_t sequence) {
+  Name manifest_name(flow_name_);
+  manifest_name.setSuffix(sequence);
+
+  std::shared_ptr<core::ContentObjectManifest> manifest_probe =
+      createManifest(manifest_name);
+
+  manifest_probe->setLifetime(0);
+  manifest_probe->setPathLabel(prod_label_);
+  manifest_probe->encode();
+
+  if (*on_content_object_output_) {
+    on_content_object_output_->operator()(*socket_->getInterface(),
+                                          *manifest_probe);
+  }
+
+  DLOG_IF(INFO, VLOG_IS_ON(3)) << "Send init probe " << sequence;
+  sendContentObject(manifest_probe, true, false);
+}
+
 void RTCProductionProtocol::sendNack(uint32_t sequence) {
   auto nack = core::PacketManager<>::getInstance().getPacket<ContentObject>(
-      signer_ ? Format::HF_INET6_TCP_AH : Format::HF_INET6_TCP,
-      signer_ ? signer_->getSignatureFieldSize() : 0);
-  uint64_t now = std::chrono::duration_cast<std::chrono::milliseconds>(
-                     std::chrono::steady_clock::now().time_since_epoch())
-                     .count();
+      nack_header_format_.first, nack_header_format_.second);
+  uint64_t now = utils::SteadyTime::nowMs().count();
   uint32_t next_packet = current_seg_;
   uint32_t prod_rate = bytes_production_rate_;
 
   struct rtc::nack_packet_t header;
   header.setTimestamp(now);
   header.setProductionRate(prod_rate);
-  header.setProductionSegement(next_packet);
+  header.setProductionSegment(next_packet);
   nack->appendPayload((const uint8_t *)&header, rtc::NACK_HEADER_SIZE);
 
   Name n(flow_name_);
@@ -533,14 +823,16 @@ void RTCProductionProtocol::sendNack(uint32_t sequence) {
   nack->setLifetime(0);
   nack->setPathLabel(prod_label_);
 
-  if (signer_) {
-    signer_->signPacket(nack.get());
-  }
-
   if (!consumer_in_sync_ && on_consumer_in_sync_ &&
-      sequence < rtc::MIN_PROBE_SEQ && sequence > next_packet) {
+      rtc::ProbeHandler::getProbeType(sequence) == rtc::ProbeType::NOT_PROBE &&
+      sequence > next_packet) {
     consumer_in_sync_ = true;
-    auto interest = core::PacketManager<>::getInstance().getPacket<Interest>();
+    Packet::Format format;
+    socket_->getSocketOption(interface::GeneralTransportOptions::PACKET_FORMAT,
+                             format);
+
+    auto interest =
+        core::PacketManager<>::getInstance().getPacket<Interest>(format);
     interest->setName(n);
     on_consumer_in_sync_(*socket_->getInterface(), *interest);
   }
@@ -550,16 +842,37 @@ void RTCProductionProtocol::sendNack(uint32_t sequence) {
   }
 
   DLOG_IF(INFO, VLOG_IS_ON(3)) << "Send nack " << sequence;
-  portal_->sendContentObject(*nack);
+  sendContentObject(nack, true, false);
 }
 
-void RTCProductionProtocol::onFecPackets(
-    std::vector<std::pair<uint32_t, fec::buffer>> &packets) {
+void RTCProductionProtocol::sendContentObject(
+    std::shared_ptr<ContentObject> content_object, bool nack, bool fec) {
+  bool is_ah = _is_ah(content_object->getFormat());
+
+  // Compute signature
+  if (is_ah) {
+    signer_->signPacket(content_object.get());
+  }
+
+  portal_->sendContentObject(*content_object);
+
+  // Compute and save data packet digest
+  if (making_manifest_ && !is_ah) {
+    auth::CryptoHashType hash_algo;
+    socket_->getSocketOption(interface::GeneralTransportOptions::HASH_ALGORITHM,
+                             hash_algo);
+    manifest_entries_.push({content_object->getName().getSuffix(),
+                            content_object->computeDigest(hash_algo)});
+  }
+}
+
+void RTCProductionProtocol::onFecPackets(fec::BufferArray &packets) {
   DLOG_IF(INFO, VLOG_IS_ON(3))
       << "Produced " << packets.size() << " FEC packets";
+
   for (auto &packet : packets) {
     auto content_object =
-        std::static_pointer_cast<ContentObject>(packet.second);
+        std::static_pointer_cast<ContentObject>(packet.getBuffer());
     content_object->prepend(content_object->headerSize() +
                             rtc::DATA_HEADER_SIZE);
     pending_fec_packets_.push(std::move(content_object));
@@ -569,19 +882,21 @@ void RTCProductionProtocol::onFecPackets(
 fec::buffer RTCProductionProtocol::getBuffer(std::size_t size) {
   DLOG_IF(INFO, VLOG_IS_ON(3))
       << "Asked buffer for FEC symbol of size " << size;
+
   auto ret = core::PacketManager<>::getInstance().getPacket<ContentObject>(
-      signer_ ? Format::HF_INET6_TCP_AH : Format::HF_INET6_TCP,
-      signer_ ? signer_->getSignatureFieldSize() : 0);
+      fec_header_format_.first, fec_header_format_.second);
+
   ret->updateLength(rtc::DATA_HEADER_SIZE + size);
   ret->append(rtc::DATA_HEADER_SIZE + size);
   ret->trimStart(ret->headerSize() + rtc::DATA_HEADER_SIZE);
+
   DLOG_IF(INFO, VLOG_IS_ON(3))
       << "Responding with buffer of length " << ret->length();
-  assert(ret->length() >= size);
+  DCHECK(ret->length() >= size);
 
   return ret;
 }
 
 }  // namespace protocol
 
-}  // end namespace transport
+}  // namespace transport