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>

6 files changed, 316 insertions, 288 deletions

diff --git a/libtransport/src/protocols/fec/CMakeLists.txt b/libtransport/src/protocols/fec/CMakeLists.txt
index 6d61ae043..8ae0a7360 100644
--- a/libtransport/src/protocols/fec/CMakeLists.txt
+++ b/libtransport/src/protocols/fec/CMakeLists.txt
@@ -1,4 +1,4 @@
-# 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:
diff --git a/libtransport/src/protocols/fec/fec.cc b/libtransport/src/protocols/fec/fec.cc
index 16a04cb98..912e7a40f 100644
--- a/libtransport/src/protocols/fec/fec.cc
+++ b/libtransport/src/protocols/fec/fec.cc
@@ -44,6 +44,7 @@
 
 #include "fec.h"
 
+#include <assert.h>
 #include <hicn/transport/portability/platform.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -60,72 +61,6 @@
 #endif
 
 /*
- * compatibility stuff
- */
-#ifdef MSDOS /* but also for others, e.g. sun... */
-#define NEED_BCOPY
-#define bcmp(a, b, n) memcmp(a, b, n)
-#endif
-
-#ifdef ANDROID
-#define bcmp(a, b, n) memcmp(a, b, n)
-#endif
-
-#ifdef NEED_BCOPY
-#define bcopy(s, d, siz) memcpy((d), (s), (siz))
-#define bzero(d, siz) memset((d), '\0', (siz))
-#endif
-
-/*
- * stuff used for testing purposes only
- */
-
-#ifdef TEST
-#define DEB(x)
-#define DDB(x) x
-#define DEBUG 0 /* minimal debugging */
-#ifdef MSDOS
-#include <time.h>
-struct timeval {
-  unsigned long ticks;
-};
-#define gettimeofday(x, dummy) \
-  { (x)->ticks = clock(); }
-#define DIFF_T(a, b) (1 + 1000000 * (a.ticks - b.ticks) / CLOCKS_PER_SEC)
-typedef unsigned long u_long;
-typedef unsigned short u_short;
-#else /* typically, unix systems */
-#include <sys/time.h>
-#define DIFF_T(a, b) \
-  (1 + 1000000 * (a.tv_sec - b.tv_sec) + (a.tv_usec - b.tv_usec))
-#endif
-
-#define TICK(t)                                  \
-  {                                              \
-    struct timeval x;                            \
-    gettimeofday(&x, NULL);                      \
-    t = x.tv_usec + 1000000 * (x.tv_sec & 0xff); \
-  }
-#define TOCK(t)               \
-  {                           \
-    u_long t1;                \
-    TICK(t1);                 \
-    if (t1 < t)               \
-      t = 256000000 + t1 - t; \
-    else                      \
-      t = t1 - t;             \
-    if (t == 0) t = 1;        \
-  }
-
-u_long ticks[10]; /* vars for timekeeping */
-#else
-#define DEB(x)
-#define DDB(x)
-#define TICK(x)
-#define TOCK(x)
-#endif /* TEST */
-
-/*
  * You should not need to change anything beyond this point.
  * The first part of the file implements linear algebra in GF.
  *
@@ -402,31 +337,17 @@ static void matmul(gf *a, gf *b, gf *c, int n, int k, int m) {
   }
 }
 
-#ifdef DEBUGG
-/*
- * returns 1 if the square matrix is identiy
- * (only for test)
- */
-static int is_identity(gf *m, int k) {
-  int row, col;
-  for (row = 0; row < k; row++)
-    for (col = 0; col < k; col++)
-      if ((row == col && *m != 1) || (row != col && *m != 0))
-        return 0;
-      else
-        m++;
-  return 1;
-}
-#endif /* debug */
-
 /*
  * invert_mat() takes a matrix and produces its inverse
  * k is the size of the matrix.
  * (Gauss-Jordan, adapted from Numerical Recipes in C)
  * Return non-zero if singular.
  */
-DEB(int pivloops = 0; int pivswaps = 0; /* diagnostic */)
+int pivloops = 0;
+int pivswaps = 0; /* diagnostic */
 static int invert_mat(gf *src, int k) {
+  assert(k > 0);
+
   gf c, *p;
   int irow, icol, row, col, i, ix;
 
@@ -436,9 +357,9 @@ static int invert_mat(gf *src, int k) {
   int *ipiv = (int *)my_malloc(k * sizeof(int), "ipiv");
   gf *id_row = NEW_GF_MATRIX(1, k);
   gf *temp_row = NEW_GF_MATRIX(1, k);
-
-  bzero(id_row, k * sizeof(gf));
-  DEB(pivloops = 0; pivswaps = 0; /* diagnostic */)
+  memset(id_row, '\0', k * sizeof(gf));
+  pivloops = 0;
+  pivswaps = 0; /* diagnostic */
   /*
    * ipiv marks elements already used as pivots.
    */
@@ -459,7 +380,7 @@ static int invert_mat(gf *src, int k) {
     for (row = 0; row < k; row++) {
       if (ipiv[row] != 1) {
         for (ix = 0; ix < k; ix++) {
-          DEB(pivloops++;)
+          pivloops++;
           if (ipiv[ix] == 0) {
             if (src[row * k + ix] != 0) {
               irow = row;
@@ -497,12 +418,9 @@ static int invert_mat(gf *src, int k) {
       fprintf(stderr, "singular matrix 2\n");
       goto fail;
     }
-    if (c != 1) { /* otherwhise this is a NOP */
-      /*
-       * this is done often , but optimizing is not so
-       * fruitful, at least in the obvious ways (unrolling)
-       */
-      DEB(pivswaps++;)
+
+    if (c != 1) {
+      pivswaps++;
       c = inverse[c];
       pivot_row[icol] = 1;
       for (ix = 0; ix < k; ix++) pivot_row[ix] = gf_mul(c, pivot_row[ix]);
@@ -515,7 +433,7 @@ static int invert_mat(gf *src, int k) {
      * we can optimize the addmul).
      */
     id_row[icol] = 1;
-    if (bcmp(pivot_row, id_row, k * sizeof(gf)) != 0) {
+    if (memcmp(pivot_row, id_row, k * sizeof(gf)) != 0) {
       for (p = src, ix = 0; ix < k; ix++, p += k) {
         if (ix != icol) {
           c = p[icol];
@@ -560,6 +478,8 @@ fail:
  */
 
 int invert_vdm(gf *src, int k) {
+  assert(k > 0);
+
   int i, j, row, col;
   gf *b, *c, *p;
   gf t, xx;
@@ -614,14 +534,8 @@ int invert_vdm(gf *src, int k) {
 
 static int fec_initialized = 0;
 static void init_fec() {
-  TICK(ticks[0]);
   generate_gf();
-  TOCK(ticks[0]);
-  DDB(fprintf(stderr, "generate_gf took %ldus\n", ticks[0]);)
-  TICK(ticks[0]);
   init_mul_table();
-  TOCK(ticks[0]);
-  DDB(fprintf(stderr, "init_mul_table took %ldus\n", ticks[0]);)
   fec_initialized = 1;
 }
 
@@ -680,19 +594,14 @@ struct fec_parms *fec_new(int k, int n) {
    * k*k vandermonde matrix, multiply right the bottom n-k rows
    * by the inverse, and construct the identity matrix at the top.
    */
-  TICK(ticks[3]);
   invert_vdm(tmp_m, k); /* much faster than invert_mat */
   matmul(tmp_m + k * k, tmp_m, retval->enc_matrix + k * k, n - k, k, k);
   /*
    * the upper matrix is I so do not bother with a slow multiply
    */
-  bzero(retval->enc_matrix, k * k * sizeof(gf));
+  memset(retval->enc_matrix, '\0', k * k * sizeof(gf));
   for (p = retval->enc_matrix, col = 0; col < k; col++, p += k + 1) *p = 1;
   free(tmp_m);
-  TOCK(ticks[3]);
-
-  DDB(fprintf(stderr, "--- %ld us to build encoding matrix\n", ticks[3]);)
-  DEB(pr_matrix(retval->enc_matrix, n, k, "encoding_matrix");)
   return retval;
 }
 
@@ -708,10 +617,10 @@ void fec_encode(struct fec_parms *code, gf *src[], gf *fec, int index, int sz) {
   if (GF_BITS > 8) sz /= 2;
 
   if (index < k)
-    bcopy(src[index], fec, sz * sizeof(gf));
+    memcpy(fec, src[index], sz * sizeof(gf));
   else if (index < code->n) {
     p = &(code->enc_matrix[index * k]);
-    bzero(fec, sz * sizeof(gf));
+    memset(fec, '\0', sz * sizeof(gf));
     for (i = 0; i < k; i++) addmul(fec, src[i], p[i], sz);
   } else
     fprintf(stderr, "Invalid index %d (max %d)\n", index, code->n - 1);
@@ -733,22 +642,13 @@ static int shuffle(gf *pkt[], int index[], int k) {
       int c = index[i];
 
       if (index[c] == c) {
-        DEB(fprintf(stderr, "\nshuffle, error at %d\n", i);)
+        fprintf(stderr, "\nshuffle, error at %d\n", i);
         return 1;
       }
       SWAP(index[i], index[c], int);
       SWAP(pkt[i], pkt[c], gf *);
     }
   }
-  DEB(/* just test that it works... */
-      for (i = 0; i < k; i++) {
-        if (index[i] < k && index[i] != i) {
-          fprintf(stderr, "shuffle: after\n");
-          for (i = 0; i < k; i++) fprintf(stderr, "%3d ", index[i]);
-          fprintf(stderr, "\n");
-          return 1;
-        }
-      })
   return 0;
 }
 
@@ -757,20 +657,16 @@ static int shuffle(gf *pkt[], int index[], int k) {
  * indexes. The matrix must be already allocated as
  * a vector of k*k elements, in row-major order
  */
-static gf *build_decode_matrix(struct fec_parms *code, gf *pkt[], int index[]) {
+static gf *build_decode_matrix(struct fec_parms *code, int index[]) {
   int i, k = code->k;
   gf *p, *matrix = NEW_GF_MATRIX(k, k);
 
-  TICK(ticks[9]);
   for (i = 0, p = matrix; i < k; i++, p += k) {
-#if 1 /* this is simply an optimization, not very useful indeed */
     if (index[i] < k) {
-      bzero(p, k * sizeof(gf));
+      memset(p, '\0', k * sizeof(gf));
       p[i] = 1;
-    } else
-#endif
-        if (index[i] < code->n)
-      bcopy(&(code->enc_matrix[index[i] * k]), p, k * sizeof(gf));
+    } else if (index[i] < code->n)
+      memcpy(p, &(code->enc_matrix[index[i] * k]), k * sizeof(gf));
     else {
       fprintf(stderr, "decode: invalid index %d (max %d)\n", index[i],
               code->n - 1);
@@ -778,12 +674,10 @@ static gf *build_decode_matrix(struct fec_parms *code, gf *pkt[], int index[]) {
       return NULL;
     }
   }
-  TICK(ticks[9]);
   if (invert_mat(matrix, k)) {
     free(matrix);
     matrix = NULL;
   }
-  TOCK(ticks[9]);
   return matrix;
 }
 
@@ -800,39 +694,29 @@ static gf *build_decode_matrix(struct fec_parms *code, gf *pkt[], int index[]) {
  */
 int fec_decode(struct fec_parms *code, gf *pkt[], int index[], int sz) {
   gf *m_dec;
-  gf **new_pkt;
+  gf **new_pkt = nullptr;
   int row, col, k = code->k;
+  int i = 0;
 
   if (GF_BITS > 8) sz /= 2;
 
   if (shuffle(pkt, index, k)) /* error if true */
     return 1;
-  m_dec = build_decode_matrix(code, pkt, index);
+  m_dec = build_decode_matrix(code, index);
 
   if (m_dec == NULL) return 1; /* error */
   /*
    * do the actual decoding
    */
-  new_pkt = (gf **)my_malloc(k * sizeof(gf *), "new pkt pointers");
+  new_pkt = pkt + k;
   for (row = 0; row < k; row++) {
     if (index[row] >= k) {
-      new_pkt[row] = (gf *)my_malloc(sz * sizeof(gf), "new pkt buffer");
-      bzero(new_pkt[row], sz * sizeof(gf));
+      memset(new_pkt[i], '\0', sz * sizeof(gf));
       for (col = 0; col < k; col++)
-        addmul(new_pkt[row], pkt[col], m_dec[row * k + col], sz);
-    }
-  }
-  /*
-   * move pkts to their final destination
-   */
-  for (row = 0; row < k; row++) {
-    if (index[row] >= k) {
-      bcopy(new_pkt[row], pkt[row], sz * sizeof(gf));
-      free(new_pkt[row]);
+        addmul(new_pkt[i], pkt[col], m_dec[row * k + col], sz);
+      i++;
     }
   }
-  free(new_pkt);
   free(m_dec);
-
   return 0;
 }
diff --git a/libtransport/src/protocols/fec/rely.cc b/libtransport/src/protocols/fec/rely.cc
index 7a30a62e2..d4d98a90b 100644
--- a/libtransport/src/protocols/fec/rely.cc
+++ b/libtransport/src/protocols/fec/rely.cc
@@ -23,38 +23,39 @@ namespace transport {
 namespace protocol {
 namespace fec {
 
-RelyEncoder::RelyEncoder(uint32_t k, uint32_t n, uint32_t seq_offset)
+RelyEncoder::RelyEncoder(uint32_t k, uint32_t n, uint32_t /* seq_offset */)
     : RelyBase(k, n) {
   configure(kmtu, ktimeout, kmax_stream_size);
   set_repair_trigger(k_, n_ - k_, n_ - k_);
 }
 
 void RelyEncoder::onPacketProduced(core::ContentObject &content_object,
-                                   uint32_t offset) {
+                                   uint32_t offset, uint32_t metadata) {
   // Get pointer to payload, leaving space to insert FEC header.
   // TODO Check if this additional header is really needed.
-  auto data = content_object.writableData() + offset - sizeof(fec_header);
-  auto length = content_object.length() - offset + sizeof(fec_header);
+  auto data = content_object.writableData() + offset - sizeof(fec_metadata);
+  auto length = content_object.length() - offset + sizeof(fec_metadata);
 
   // Check packet length does not exceed maximum length supported by the
   // encoder (otherwise segmentation would take place).
-  assert(length < max_packet_bytes());
+  DCHECK(length < max_packet_bytes());
   DLOG_IF(INFO, VLOG_IS_ON(4))
-      << "Encoding packet of length " << length - sizeof(fec_header);
+      << "Encoding packet of length " << length - sizeof(fec_metadata);
 
-  // Get the suffix. With rely we need to write it in the fec_header in order to
-  // be able to recognize the seq number upon recovery.
+  // Get the suffix. With rely we need to write it in the fec_metadata in order
+  // to be able to recognize the seq number upon recovery.
   auto suffix = content_object.getName().getSuffix();
   DLOG_IF(INFO, VLOG_IS_ON(4)) << "Producing packet " << suffix
                                << " (index == " << current_index_ << ")";
 
-  // Consume payload. Add fec_header in front before feeding payload to encoder,
-  // and copy original content of packet
-  fec_header *h = reinterpret_cast<fec_header *>(data);
-  fec_header copy = *h;
+  // Consume payload. Add fec_metadata in front before feeding payload to
+  // encoder, and copy original content of packet
+  fec_metadata *h = reinterpret_cast<fec_metadata *>(data);
+  fec_metadata copy = *h;
   h->setSeqNumberBase(suffix);
+  h->setMetadataBase(metadata);
   auto packets = consume(data, length, getCurrentTime());
-  assert(packets == 1);
+  DCHECK(packets == 1);
 
   // Update packet counter
   current_index_ += packets;
@@ -62,7 +63,7 @@ void RelyEncoder::onPacketProduced(core::ContentObject &content_object,
   // Restore original packet content and increment data pointer to the correct
   // position
   *h = copy;
-  data += sizeof(fec_header);
+  data += sizeof(fec_metadata);
 
   // Check position of this packet inside N size block
   auto i = current_index_ % n_;
@@ -74,24 +75,24 @@ void RelyEncoder::onPacketProduced(core::ContentObject &content_object,
     // TODO Optimize it by copying only the RELY header
 
     // Be sure encoder can produce
-    assert(can_produce());
+    DCHECK(can_produce());
 
     // Check new payload size and make sure it fits in packet buffer
     auto new_payload_size = produce_bytes();
     int difference = new_payload_size - length;
 
-    assert(difference > 0);
-    assert(content_object.ensureCapacity(difference));
+    DCHECK(difference > 0);
+    DCHECK(content_object.ensureCapacity(difference));
 
     // Update length
     DLOG_IF(INFO, VLOG_IS_ON(4)) << "The packet length will be incremented by "
-                                 << difference + sizeof(fec_header);
-    content_object.append(difference + sizeof(fec_header));
+                                 << difference + sizeof(fec_metadata);
+    content_object.append(difference + sizeof(fec_metadata));
     content_object.updateLength();
 
     // Make sure we got a source packet, otherwise we would put a repair symbol
     // in a source packet
-    assert(rely::packet_is_systematic(produce_data()));
+    DCHECK(rely::packet_is_systematic(produce_data()));
 
     // Copy rely packet replacing old source packet.
     std::memcpy(data, produce_data(), new_payload_size);
@@ -111,7 +112,7 @@ void RelyEncoder::onPacketProduced(core::ContentObject &content_object,
   while (can_produce()) {
     // The current index MUST be k_, because we enforce n - k repair to be
     // produced after k sources
-    assert(current_index_ == k_);
+    DCHECK(current_index_ == k_);
 
     buffer packet;
     if (!buffer_callback_) {
@@ -130,7 +131,7 @@ void RelyEncoder::onPacketProduced(core::ContentObject &content_object,
     std::memcpy(packet->writableData(), produce_data(), produce_bytes());
 
     // Push symbol in repair_packets
-    packets_.emplace_back(0, std::move(packet));
+    packets_.emplace_back(0, metadata, std::move(packet));
 
     // Advance the encoder
     produce_next();
@@ -143,7 +144,7 @@ void RelyEncoder::onPacketProduced(core::ContentObject &content_object,
   // If we have generated repair symbols, let's notify caller via the installed
   // callback
   if (packets_.size()) {
-    assert(packets_.size() == n_ - k_);
+    DCHECK(packets_.size() == n_ - k_);
     fec_callback_(packets_);
     packets_.clear();
     current_index_ = 0;
@@ -156,7 +157,7 @@ RelyDecoder::RelyDecoder(uint32_t k, uint32_t n, uint32_t seq_offset)
 }
 
 void RelyDecoder::onDataPacket(core::ContentObject &content_object,
-                               uint32_t offset) {
+                               uint32_t offset, uint32_t metadata) {
   // Adjust pointers to point to packet payload
   auto data = content_object.writableData() + offset;
   auto size = content_object.length() - offset;
@@ -164,30 +165,38 @@ void RelyDecoder::onDataPacket(core::ContentObject &content_object,
   // Pass payload to decoder
   consume(data, size, getCurrentTime());
 
+  producePackets();
+}
+
+void RelyDecoder::producePackets() {
   // Drain decoder if possible
   while (can_produce()) {
-    // Get size of decoded packet
-    auto size = produce_bytes();
-
-    // Get buffer to copy packet in
-    auto packet = core::PacketManager<>::getInstance().getMemBuf();
+    auto fec_header_size = sizeof(fec_metadata);
+    auto payload_size = produce_bytes() - sizeof(fec_metadata);
 
-    // Copy buffer
-    packet->append(size);
-    std::memcpy(packet->writableData(), produce_data(), size);
+    buffer packet;
+    if (!buffer_callback_) {
+      packet = core::PacketManager<>::getInstance().getMemBuf();
+      packet->append(payload_size);
+    } else {
+      packet = buffer_callback_(payload_size);
+    }
 
     // Read seq number
-    fec_header *h = reinterpret_cast<fec_header *>(packet->writableData());
+    const fec_metadata *h =
+        reinterpret_cast<const fec_metadata *>(produce_data());
     uint32_t index = h->getSeqNumberBase();
+    uint32_t metadata = h->getMetadataBase();
 
     DLOG_IF(INFO, VLOG_IS_ON(4))
         << "The index written in the packet is " << index;
 
-    // Remove FEC header
-    packet->trimStart(sizeof(fec_header));
+    // Copy payload
+    std::memcpy(packet->writableData(), produce_data() + fec_header_size,
+                payload_size);
 
     // Save packet in buffer
-    packets_.emplace_back(index, std::move(packet));
+    packets_.emplace_back(index, metadata, std::move(packet));
 
     // Advance to next packet
     produce_next();
@@ -198,8 +207,28 @@ void RelyDecoder::onDataPacket(core::ContentObject &content_object,
     fec_callback_(packets_);
     packets_.clear();
   }
+
+  flushOutOfOrder();
+}
+
+void RelyDecoder::flushOutOfOrder() {
+  if (flush_timer_ == nullptr) return;
+  flush_timer_->cancel();
+
+  if (has_upcoming_flush()) {
+    flush_timer_->expires_from_now(std::chrono::milliseconds(
+        std::max((int64_t)0, upcoming_flush(getCurrentTime()))));
+
+    flush_timer_->async_wait([this](const std::error_code &ec) {
+      if (ec) return;
+      if (has_upcoming_flush()) {
+        flush(getCurrentTime());
+        producePackets();
+      }
+    });
+  }
 }
 
 }  // namespace fec
 }  // namespace protocol
-}  // namespace transport
\ No newline at end of file
+}  // namespace transport
diff --git a/libtransport/src/protocols/fec/rely.h b/libtransport/src/protocols/fec/rely.h
index bfbdb30bc..001a26002 100644
--- a/libtransport/src/protocols/fec/rely.h
+++ b/libtransport/src/protocols/fec/rely.h
@@ -33,8 +33,12 @@ namespace fec {
  * @brief Table of used codes.
  */
 #define foreach_rely_fec_type \
+  _(Rely, 1, 2)               \
   _(Rely, 1, 3)               \
+  _(Rely, 1, 4)               \
   _(Rely, 2, 3)               \
+  _(Rely, 2, 6)               \
+  _(Rely, 3, 9)               \
   _(Rely, 4, 5)               \
   _(Rely, 4, 6)               \
   _(Rely, 4, 7)               \
@@ -74,11 +78,17 @@ class RelyBase : public virtual FECBase {
    * decoding operations. It may be removed once we know the meaning of the
    * fields in the rely header.
    */
-  struct fec_header {
-    uint32_t seq_number;
-
+  class fec_metadata {
+   public:
     void setSeqNumberBase(uint32_t suffix) { seq_number = htonl(suffix); }
-    uint32_t getSeqNumberBase() { return ntohl(seq_number); }
+    uint32_t getSeqNumberBase() const { return ntohl(seq_number); }
+
+    void setMetadataBase(uint32_t value) { metadata = htonl(value); }
+    uint32_t getMetadataBase() const { return ntohl(metadata); }
+
+   private:
+    uint32_t seq_number;
+    uint32_t metadata;
   };
 
   /**
@@ -112,21 +122,20 @@ class RelyBase : public virtual FECBase {
 #if RELY_DEBUG
     return time_++;
 #else
-    auto _time = utils::SteadyClock::now().time_since_epoch();
-    auto time = std::chrono::duration_cast<utils::Milliseconds>(_time).count();
-    return time;
+    return utils::SteadyTime::nowMs().count();
 #endif
   }
 
- protected:
   uint32_t k_;
   uint32_t n_;
+
   std::uint32_t seq_offset_;
+
   /**
    * @brief Vector of packets to be passed to caller callbacks. For encoder it
    * will contain the repair packets, for decoder the recovered sources.
    */
-  std::vector<std::pair<uint32_t, buffer>> packets_;
+  BufferArray packets_;
 
   /**
    * @brief Current index to be used for local packet count.
@@ -142,50 +151,54 @@ class RelyBase : public virtual FECBase {
  * @brief The Rely Encoder implementation.
  *
  */
-class RelyEncoder : private RelyBase,
-                    private rely::encoder,
-                    public ProducerFEC {
+class RelyEncoder : RelyBase, rely::encoder, public ProducerFEC {
  public:
   RelyEncoder(uint32_t k, uint32_t n, uint32_t seq_offset = 0);
   /**
    * Producers will call this function when they produce a data packet.
    */
-  void onPacketProduced(core::ContentObject &content_object,
-                        uint32_t offset) override;
+  void onPacketProduced(core::ContentObject &content_object, uint32_t offset,
+                        uint32_t metadata = FECBase::INVALID_METADATA) override;
 
   /**
    * @brief Get the fec header size, if added to source packets
    */
   std::size_t getFecHeaderSize() override {
-    return header_bytes() + sizeof(fec_header) + 4;
+    return header_bytes() + sizeof(fec_metadata) + 4;
   }
 
-  void reset() override {}
+  void reset() override {
+    // Nothing to do here
+  }
 };
 
-class RelyDecoder : private RelyBase,
-                    private rely::decoder,
-                    public ConsumerFEC {
+class RelyDecoder : RelyBase, rely::decoder, public ConsumerFEC {
  public:
   RelyDecoder(uint32_t k, uint32_t n, uint32_t seq_offset = 0);
 
   /**
    * Consumers will call this function when they receive a data packet
    */
-  void onDataPacket(core::ContentObject &content_object,
-                    uint32_t offset) override;
+  void onDataPacket(core::ContentObject &content_object, uint32_t offset,
+                    uint32_t metadata = FECBase::INVALID_METADATA) override;
 
   /**
    * @brief Get the fec header size, if added to source packets
    */
   std::size_t getFecHeaderSize() override {
-    return header_bytes() + sizeof(fec_header);
+    return header_bytes() + sizeof(fec_metadata);
+  }
+
+  void reset() override {
+    // Nothing to do here
   }
 
-  void reset() override {}
+ private:
+  void producePackets();
+  void flushOutOfOrder();
 };
 
 }  // namespace fec
 
 }  // namespace protocol
-}  // namespace transport
\ No newline at end of file
+}  // namespace transport
diff --git a/libtransport/src/protocols/fec/rs.cc b/libtransport/src/protocols/fec/rs.cc
index 2c23d515d..9c0a3d4fb 100644
--- a/libtransport/src/protocols/fec/rs.cc
+++ b/libtransport/src/protocols/fec/rs.cc
@@ -46,23 +46,26 @@ bool BlockCode::addRepairSymbol(const fec::buffer &packet, uint32_t i,
   to_decode_ = true;
   DLOG_IF(INFO, VLOG_IS_ON(4)) << "Adding symbol of size " << packet->length();
   return addSymbol(packet, i, offset,
-                   packet->length() - sizeof(fec_header) - offset);
+                   packet->length() - sizeof(fec_header) - offset,
+                   FECBase::INVALID_METADATA);
 }
 
 bool BlockCode::addSourceSymbol(const fec::buffer &packet, uint32_t i,
-                                uint32_t offset) {
+                                uint32_t offset, uint32_t metadata) {
   DLOG_IF(INFO, VLOG_IS_ON(4)) << "Adding source symbol of size "
                                << packet->length() << ", offset " << offset;
-  return addSymbol(packet, i, offset, packet->length() - offset);
+  return addSymbol(packet, i, offset, packet->length() - offset, metadata);
 }
 
 bool BlockCode::addSymbol(const fec::buffer &packet, uint32_t i,
-                          uint32_t offset, std::size_t size) {
+                          uint32_t offset, std::size_t size,
+                          uint32_t metadata) {
   if (size > max_buffer_size_) {
     max_buffer_size_ = size;
   }
 
-  operator[](current_block_size_++) = std::make_tuple(i, packet, offset);
+  operator[](current_block_size_) = RSBufferInfo(offset, i, metadata, packet);
+  current_block_size_++;
 
   if (current_block_size_ >= k_) {
     if (to_decode_) {
@@ -80,12 +83,13 @@ bool BlockCode::addSymbol(const fec::buffer &packet, uint32_t i,
 
 void BlockCode::encode() {
   gf *data[n_];
-  uint32_t base = std::get<0>(operator[](0));
+  uint32_t base = operator[](0).getIndex();
 
   // Set packet length in first 2 bytes
   for (uint32_t i = 0; i < k_; i++) {
-    auto &packet = std::get<1>(operator[](i));
-    auto offset = std::get<2>(operator[](i));
+    auto &packet = operator[](i).getBuffer();
+    auto offset = operator[](i).getOffset();
+    auto metadata_base = operator[](i).getMetadata();
 
     auto ret =
         packet->ensureCapacityAndFillUnused(max_buffer_size_ + offset, 0);
@@ -98,10 +102,11 @@ void BlockCode::encode() {
     // Buffers should hold 2 *after* the padding, in order to be
     // able to set the length for the encoding operation.
     // packet->trimStart(offset);
-    uint16_t *length = reinterpret_cast<uint16_t *>(packet->writableData() +
-                                                    max_buffer_size_ + offset);
+    fec_metadata *metadata = reinterpret_cast<fec_metadata *>(
+        packet->writableData() + max_buffer_size_ + offset);
     auto buffer_length = packet->length() - offset;
-    *length = htons(buffer_length);
+    metadata->setPacketLength(buffer_length);
+    metadata->setMetadataBase(metadata_base);
 
     DLOG_IF(INFO, VLOG_IS_ON(4)) << "Current buffer size: " << packet->length();
 
@@ -109,7 +114,7 @@ void BlockCode::encode() {
   }
 
   // Finish to fill source block with the buffers to hold the repair symbols
-  auto length = max_buffer_size_ + sizeof(fec_header) + LEN_SIZE_BYTES;
+  auto length = max_buffer_size_ + sizeof(fec_header) + METADATA_BYTES;
   for (uint32_t i = k_; i < n_; i++) {
     buffer packet;
     if (!params_.buffer_callback_) {
@@ -133,19 +138,20 @@ void BlockCode::encode() {
     DLOG_IF(INFO, VLOG_IS_ON(4)) << "Current symbol size: " << packet->length();
 
     data[i] = packet->writableData();
-    operator[](i) = std::make_tuple(i, std::move(packet), uint32_t(0));
+    operator[](i) = RSBufferInfo(uint32_t(0), i, FECBase::INVALID_METADATA,
+                                 std::move(packet));
   }
 
   // Generate repair symbols and put them in corresponding buffers
   DLOG_IF(INFO, VLOG_IS_ON(4))
       << "Calling encode with max_buffer_size_ = " << max_buffer_size_;
   for (uint32_t i = k_; i < n_; i++) {
-    fec_encode(code_, data, data[i], i, max_buffer_size_ + LEN_SIZE_BYTES);
+    fec_encode(code_, data, data[i], i, max_buffer_size_ + METADATA_BYTES);
   }
 
   // Re-include header in repair packets
   for (uint32_t i = k_; i < n_; i++) {
-    auto &packet = std::get<1>(operator[](i));
+    auto &packet = operator[](i).getBuffer();
     packet->prepend(sizeof(fec_header));
     DLOG_IF(INFO, VLOG_IS_ON(4))
         << "Produced repair symbol of size = " << packet->length();
@@ -153,16 +159,31 @@ void BlockCode::encode() {
 }
 
 void BlockCode::decode() {
-  gf *data[k_];
+  gf *data[n_];
   uint32_t index[k_];
+  buffer aux_fec_packets[n_ - k_];
+  // FEC packet number  k0
+  uint32_t k0 = 0;
+
+  // Reorder block by index with in-place sorting
+  for (uint32_t i = 0; i < k_;) {
+    uint32_t idx = operator[](i).getIndex();
+    if (idx >= k_ || idx == i) {
+      i++;
+    } else {
+      std::swap(operator[](i), operator[](idx));
+    }
+  }
 
   for (uint32_t i = 0; i < k_; i++) {
-    auto &packet = std::get<1>(operator[](i));
-    index[i] = std::get<0>(operator[](i));
-    auto offset = std::get<2>(operator[](i));
+    auto &packet = operator[](i).getBuffer();
+    index[i] = operator[](i).getIndex();
+    auto offset = operator[](i).getOffset();
+    auto metadata_base = operator[](i).getMetadata();
     sorted_index_[i] = index[i];
 
     if (index[i] < k_) {
+      operator[](i).setReceived();
       DLOG_IF(INFO, VLOG_IS_ON(4))
           << "DECODE SOURCE - index " << index[i]
           << " - Current buffer size: " << packet->length();
@@ -173,49 +194,51 @@ void BlockCode::decode() {
       // able to set the length for the encoding operation
       packet->trimStart(offset);
       packet->ensureCapacityAndFillUnused(max_buffer_size_, 0);
-      uint16_t *length = reinterpret_cast<uint16_t *>(
-          packet->writableData() + max_buffer_size_ - LEN_SIZE_BYTES);
-
-      *length = htons(packet->length());
+      fec_metadata *metadata = reinterpret_cast<fec_metadata *>(
+          packet->writableData() + max_buffer_size_ - METADATA_BYTES);
+      metadata->setPacketLength(packet->length());
+      metadata->setMetadataBase(metadata_base);
     } else {
       DLOG_IF(INFO, VLOG_IS_ON(4))
           << "DECODE SYMBOL - index " << index[i]
           << " - Current buffer size: " << packet->length();
       packet->trimStart(sizeof(fec_header) + offset);
+      aux_fec_packets[k0] = core::PacketManager<>::getInstance().getMemBuf();
+      data[k_ + k0] = aux_fec_packets[k0]->writableData();
+      k0++;
     }
-
     data[i] = packet->writableData();
   }
-
   // We decode the source block
   DLOG_IF(INFO, VLOG_IS_ON(4))
       << "Calling decode with max_buffer_size_ = " << max_buffer_size_;
+
   fec_decode(code_, data, reinterpret_cast<int *>(index), max_buffer_size_);
 
   // Find the index in the block for recovered packets
-  for (uint32_t i = 0; i < k_; i++) {
-    if (index[i] != i) {
-      for (uint32_t j = 0; j < k_; j++)
-        if (sorted_index_[j] == uint32_t(index[i])) {
-          sorted_index_[j] = i;
-        }
-    }
-  }
-
-  // Reorder block by index with in-place sorting
-  for (uint32_t i = 0; i < k_; i++) {
-    for (uint32_t j = sorted_index_[i]; j != i; j = sorted_index_[i]) {
-      std::swap(sorted_index_[j], sorted_index_[i]);
-      std::swap(operator[](j), operator[](i));
+  for (uint32_t i = 0, j = 0; i < k_; i++) {
+    if (index[i] >= k_) {
+      operator[](i).setBuffer(aux_fec_packets[j++]);
+      operator[](i).setIndex(i);
     }
   }
 
   // Adjust length according to the one written in the source packet
   for (uint32_t i = 0; i < k_; i++) {
-    auto &packet = std::get<1>(operator[](i));
-    uint16_t *length = reinterpret_cast<uint16_t *>(
-        packet->writableData() + max_buffer_size_ - LEN_SIZE_BYTES);
-    packet->setLength(ntohs(*length));
+    auto &packet = operator[](i).getBuffer();
+    fec_metadata *metadata = reinterpret_cast<fec_metadata *>(
+        packet->writableData() + max_buffer_size_ - METADATA_BYTES);
+    // Adjust buffer length
+    packet->setLength(metadata->getPacketLength());
+    // Adjust metadata
+    operator[](i).setMetadata(metadata->getMetadataBase());
+
+    // reset the point to the beginning of the packets for all received packets
+    if (operator[](i).getReceived()) {
+      auto &packet = operator[](i).getBuffer();
+      auto offset = operator[](i).getOffset();
+      packet->prepend(offset);
+    }
   }
 }
 
@@ -252,12 +275,11 @@ RSEncoder::RSEncoder(uint32_t k, uint32_t n, uint32_t seq_offset)
       source_block_(k_, n_, seq_offset_, current_code_, *this) {}
 
 void RSEncoder::consume(const fec::buffer &packet, uint32_t index,
-                        uint32_t offset) {
-  if (!source_block_.addSourceSymbol(packet, index, offset)) {
-    std::vector<std::pair<uint32_t, buffer>> repair_packets;
+                        uint32_t offset, uint32_t metadata) {
+  if (!source_block_.addSourceSymbol(packet, index, offset, metadata)) {
+    fec::BufferArray repair_packets;
     for (uint32_t i = k_; i < n_; i++) {
-      repair_packets.emplace_back(std::move(std::get<0>(source_block_[i])),
-                                  std::move(std::get<1>(source_block_[i])));
+      repair_packets.emplace_back(std::move(source_block_[i]));
     }
 
     fec_callback_(repair_packets);
@@ -265,9 +287,9 @@ void RSEncoder::consume(const fec::buffer &packet, uint32_t index,
 }
 
 void RSEncoder::onPacketProduced(core::ContentObject &content_object,
-                                 uint32_t offset) {
+                                 uint32_t offset, uint32_t metadata) {
   consume(content_object.shared_from_this(),
-          content_object.getName().getSuffix(), offset);
+          content_object.getName().getSuffix(), offset, metadata);
 }
 
 RSDecoder::RSDecoder(uint32_t k, uint32_t n, uint32_t seq_offset)
@@ -276,10 +298,15 @@ RSDecoder::RSDecoder(uint32_t k, uint32_t n, uint32_t seq_offset)
 void RSDecoder::recoverPackets(SourceBlocks::iterator &src_block_it) {
   DLOG_IF(INFO, VLOG_IS_ON(4)) << "recoverPackets for " << k_;
   auto &src_block = src_block_it->second;
-  std::vector<std::pair<uint32_t, buffer>> source_packets(k_);
+  auto base_index = src_block_it->first;
+  BufferArray source_packets(k_);
+
+  // Iterate over packets in the block and adjust indexed accordingly. This must
+  // be done because indexes are from 0 to (n - k - 1), but we need indexes from
+  // base_index to base_index + (n - k - 1)
   for (uint32_t i = 0; i < src_block.getK(); i++) {
-    source_packets[i] = std::make_pair(src_block_it->first + i,
-                                       std::move(std::get<1>(src_block[i])));
+    src_block[i].setIndex(base_index + src_block[i].getIndex());
+    source_packets[i] = FECBufferInfo(std::move(src_block[i]));
   }
 
   setProcessed(src_block_it->first);
@@ -296,9 +323,9 @@ void RSDecoder::recoverPackets(SourceBlocks::iterator &src_block_it) {
 }
 
 void RSDecoder::consumeSource(const fec::buffer &packet, uint32_t index,
-                              uint32_t offset) {
+                              uint32_t offset, uint32_t metadata) {
   // Normalize index
-  assert(index >= seq_offset_);
+  DCHECK(index >= seq_offset_);
   auto i = (index - seq_offset_) % n_;
 
   // Get base
@@ -324,16 +351,19 @@ void RSDecoder::consumeSource(const fec::buffer &packet, uint32_t index,
   //    protocol that may come in the future.
   auto it = src_blocks_.find(base);
   if (it != src_blocks_.end()) {
-    auto ret = it->second.addSourceSymbol(packet, i, offset);
+    auto ret = it->second.addSourceSymbol(packet, i, offset, metadata);
     if (!ret) {
       recoverPackets(it);
     }
   } else {
     DLOG_IF(INFO, VLOG_IS_ON(4)) << "Adding to parked source packets";
-    auto ret = parked_packets_.emplace(
-        base, std::vector<std::pair<buffer, uint32_t>>());
-    ret.first->second.emplace_back(packet, i);
+    auto ret = parked_packets_.emplace(base, BufferInfoArray());
+    ret.first->second.emplace_back(offset, i, metadata, packet);
 
+    /**
+     * If we reached k source packets, we do not have any missing packet to
+     * recover via FEC. Delete the block.
+     */
     if (ret.first->second.size() >= k_) {
       setProcessed(ret.first->first);
       parked_packets_.erase(ret.first);
@@ -356,8 +386,8 @@ void RSDecoder::consumeRepair(const fec::buffer &packet, uint32_t offset) {
 
   DLOG_IF(INFO, VLOG_IS_ON(4))
       << "Decoder consume called for repair symbol. BASE = " << base
-      << ", index = " << base + i << " and i = " << i << ". K=" << k
-      << ", N=" << n;
+      << ", index = " << base + i << " and i = " << (int)i << ". K=" << (int)k
+      << ", N=" << (int)n;
 
   // check if a source block already exist for this symbol
   auto it = src_blocks_.find(base);
@@ -380,8 +410,9 @@ void RSDecoder::consumeRepair(const fec::buffer &packet, uint32_t offset) {
     auto it2 = parked_packets_.find(base);
     if (it2 != parked_packets_.end()) {
       for (auto &packet_index : it2->second) {
-        auto ret = it->second.addSourceSymbol(packet_index.first,
-                                              packet_index.second, offset);
+        auto ret = it->second.addSourceSymbol(
+            packet_index.getBuffer(), packet_index.getIndex(),
+            packet_index.getOffset(), packet_index.getMetadata());
         if (!ret) {
           recoverPackets(it);
           // Finish to delete packets in same source block that were
@@ -399,7 +430,7 @@ void RSDecoder::consumeRepair(const fec::buffer &packet, uint32_t offset) {
 }
 
 void RSDecoder::onDataPacket(core::ContentObject &content_object,
-                             uint32_t offset) {
+                             uint32_t offset, uint32_t metadata) {
   DLOG_IF(INFO, VLOG_IS_ON(4))
       << "Calling fec for data packet " << content_object.getName()
       << ". Offset: " << offset;
@@ -409,7 +440,7 @@ void RSDecoder::onDataPacket(core::ContentObject &content_object,
   if (isSymbol(suffix)) {
     consumeRepair(content_object.shared_from_this(), offset);
   } else {
-    consumeSource(content_object.shared_from_this(), suffix, offset);
+    consumeSource(content_object.shared_from_this(), suffix, offset, metadata);
   }
 }
 
diff --git a/libtransport/src/protocols/fec/rs.h b/libtransport/src/protocols/fec/rs.h
index e159ad9f7..034c32bdc 100644
--- a/libtransport/src/protocols/fec/rs.h
+++ b/libtransport/src/protocols/fec/rs.h
@@ -34,10 +34,28 @@ namespace protocol {
 namespace fec {
 
 #define foreach_rs_fec_type \
+  _(RS, 1, 2)               \
   _(RS, 1, 3)               \
+  _(RS, 1, 4)               \
+  _(RS, 2, 3)               \
+  _(RS, 2, 4)               \
+  _(RS, 2, 5)               \
+  _(RS, 2, 6)               \
+  _(RS, 3, 6)               \
+  _(RS, 3, 7)               \
+  _(RS, 3, 8)               \
+  _(RS, 3, 9)               \
+  _(RS, 3, 10)              \
+  _(RS, 3, 11)              \
+  _(RS, 3, 12)              \
   _(RS, 4, 5)               \
   _(RS, 4, 6)               \
   _(RS, 4, 7)               \
+  _(RS, 4, 8)               \
+  _(RS, 4, 9)               \
+  _(RS, 4, 10)              \
+  _(RS, 4, 11)              \
+  _(RS, 4, 12)              \
   _(RS, 6, 10)              \
   _(RS, 8, 10)              \
   _(RS, 8, 11)              \
@@ -45,6 +63,8 @@ namespace fec {
   _(RS, 8, 14)              \
   _(RS, 8, 16)              \
   _(RS, 8, 32)              \
+  _(RS, 10, 20)             \
+  _(RS, 10, 25)             \
   _(RS, 10, 30)             \
   _(RS, 10, 40)             \
   _(RS, 10, 60)             \
@@ -56,12 +76,24 @@ namespace fec {
   _(RS, 16, 27)             \
   _(RS, 17, 21)             \
   _(RS, 17, 34)             \
+  _(RS, 20, 45)             \
+  _(RS, 20, 50)             \
+  _(RS, 20, 60)             \
+  _(RS, 20, 70)             \
+  _(RS, 30, 70)             \
+  _(RS, 30, 75)             \
+  _(RS, 30, 85)             \
+  _(RS, 30, 95)             \
   _(RS, 32, 36)             \
   _(RS, 32, 41)             \
   _(RS, 32, 46)             \
   _(RS, 32, 54)             \
   _(RS, 34, 42)             \
   _(RS, 35, 70)             \
+  _(RS, 40, 95)             \
+  _(RS, 40, 100)            \
+  _(RS, 40, 110)            \
+  _(RS, 40, 120)            \
   _(RS, 52, 62)
 
 static const constexpr uint16_t MAX_SOURCE_BLOCK_SIZE = 128;
@@ -73,9 +105,24 @@ static const constexpr uint16_t MAX_SOURCE_BLOCK_SIZE = 128;
  * std::array allows to be constructed in place, saving the allocation at the
  * price os knowing in advance its size.
  */
-using Packets = std::array<std::tuple</* index */ uint32_t, /* buffer */ buffer,
-                                      uint32_t /* offset */>,
-                           MAX_SOURCE_BLOCK_SIZE>;
+class RSBufferInfo : public FECBufferInfo {
+ public:
+  RSBufferInfo() : FECBufferInfo() {}
+
+  RSBufferInfo(uint32_t offset, uint32_t index, uint32_t metadata,
+               buffer buffer)
+      : FECBufferInfo(index, metadata, buffer), offset_(offset) {}
+
+  uint32_t getOffset() { return offset_; }
+  RSBufferInfo &setOffset(uint32_t offset) {
+    offset_ = offset;
+    return *this;
+  }
+
+ private:
+  uint32_t offset_ = 0;
+};
+using Packets = std::array<RSBufferInfo, MAX_SOURCE_BLOCK_SIZE>;
 
 /**
  * FEC Header, prepended to symbol packets.
@@ -123,10 +170,32 @@ class rs;
  */
 class BlockCode : public Packets {
   /**
+   * @brief Metadata to include when encoding the buffers. This does not need to
+   * be sent over the network, but just to be included in the FEC protected
+   * bytes.
+   *
+   */
+  class __attribute__((__packed__)) fec_metadata {
+   public:
+    void setPacketLength(uint16_t length) { packet_length = htons(length); }
+    uint32_t getPacketLength() { return ntohs(packet_length); }
+
+    void setMetadataBase(uint32_t value) { metadata = htonl(value); }
+    uint32_t getMetadataBase() { return ntohl(metadata); }
+
+   private:
+    uint16_t packet_length; /* Used to get the real size of the packet after we
+                               pad it */
+    uint32_t
+        metadata; /* Caller may specify an integer for storing additional
+                     metadata that can be used when recovering the packet. */
+  };
+
+  /**
    * For variable length packet we need to prepend to the padded payload the
    * real length of the packet. This is *not* sent over the network.
    */
-  static constexpr std::size_t LEN_SIZE_BYTES = 2;
+  static constexpr std::size_t METADATA_BYTES = sizeof(fec_metadata);
 
  public:
   BlockCode(uint32_t k, uint32_t n, uint32_t seq_offset, struct fec_parms *code,
@@ -142,7 +211,8 @@ class BlockCode : public Packets {
    * Add a source symbol to the source block.
    */
   bool addSourceSymbol(const fec::buffer &packet, uint32_t i,
-                       uint32_t offset = 0);
+                       uint32_t offset = 0,
+                       uint32_t metadata = FECBase::INVALID_METADATA);
 
   /**
    * Get current length of source block.
@@ -169,7 +239,7 @@ class BlockCode : public Packets {
    * Add symbol to source block
    **/
   bool addSymbol(const fec::buffer &packet, uint32_t i, uint32_t offset,
-                 std::size_t size);
+                 std::size_t size, uint32_t metadata);
 
   /**
    * Starting from k source symbols, get the n - k repair symbols
@@ -310,10 +380,11 @@ class RSEncoder : public rs, public ProducerFEC {
   /**
    * Always consume source symbols.
    */
-  void consume(const fec::buffer &packet, uint32_t index, uint32_t offset = 0);
+  void consume(const fec::buffer &packet, uint32_t index, uint32_t offset = 0,
+               uint32_t metadata = FECBase::INVALID_METADATA);
 
-  void onPacketProduced(core::ContentObject &content_object,
-                        uint32_t offset) override;
+  void onPacketProduced(core::ContentObject &content_object, uint32_t offset,
+                        uint32_t metadata = FECBase::INVALID_METADATA) override;
 
   /**
    * @brief Get the fec header size, if added to source packets
@@ -348,8 +419,8 @@ class RSDecoder : public rs, public ConsumerFEC {
   /**
    * Consume source symbol
    */
-  void consumeSource(const fec::buffer &packet, uint32_t i,
-                     uint32_t offset = 0);
+  void consumeSource(const fec::buffer &packet, uint32_t i, uint32_t offset = 0,
+                     uint32_t metadata = FECBase::INVALID_METADATA);
 
   /**
    * Consume repair symbol
@@ -359,8 +430,8 @@ class RSDecoder : public rs, public ConsumerFEC {
   /**
    * Consumers will call this function when they receive a data packet
    */
-  void onDataPacket(core::ContentObject &content_object,
-                    uint32_t offset) override;
+  void onDataPacket(core::ContentObject &content_object, uint32_t offset,
+                    uint32_t metadata = FECBase::INVALID_METADATA) override;
 
   /**
    * @brief Get the fec header size, if added to source packets
@@ -398,8 +469,8 @@ class RSDecoder : public rs, public ConsumerFEC {
    * not make any sense to build the source block, since we received all the
    * source packet of the block.
    */
-  std::unordered_map<uint32_t, std::vector<std::pair<buffer, uint32_t>>>
-      parked_packets_;
+  using BufferInfoArray = std::vector<RSBufferInfo>;
+  std::unordered_map<uint32_t, BufferInfoArray> parked_packets_;
 };
 
 }  // namespace fec