diff --git a/src/lsa/lsa.cpp b/src/lsa/lsa.cpp
new file mode 100644
index 0000000..c0d6435
--- /dev/null
+++ b/src/lsa/lsa.cpp
@@ -0,0 +1,167 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014-2020,  The University of Memphis,
+ *                           Regents of the University of California,
+ *                           Arizona Board of Regents.
+ *
+ * This file is part of NLSR (Named-data Link State Routing).
+ * See AUTHORS.md for complete list of NLSR authors and contributors.
+ *
+ * NLSR is free software: you can redistribute it and/or modify it under the terms
+ * of the GNU General Public License as published by the Free Software Foundation,
+ * either version 3 of the License, or (at your option) any later version.
+ *
+ * NLSR is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+ * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * NLSR, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ **/
+
+#include "lsa.hpp"
+#include "nlsr.hpp"
+#include "name-prefix-list.hpp"
+#include "adjacent.hpp"
+#include "tlv/tlv-nlsr.hpp"
+
+namespace nlsr {
+
+Lsa::Lsa(const ndn::Name& originRouter, uint32_t seqNo,
+         ndn::time::system_clock::TimePoint expirationTimePoint)
+  : m_originRouter(originRouter)
+  , m_seqNo(seqNo)
+  , m_expirationTimePoint(expirationTimePoint)
+{
+}
+
+ndn::Name
+Lsa::getKey() const
+{
+  return ndn::Name(m_originRouter).append(boost::lexical_cast<std::string>((getType())));
+}
+
+template<ndn::encoding::Tag TAG>
+size_t
+Lsa::wireEncode(ndn::EncodingImpl<TAG>& encoder) const
+{
+  size_t totalLength = 0;
+
+  totalLength += prependStringBlock(encoder,
+                                    ndn::tlv::nlsr::ExpirationTime,
+                                    ndn::time::toString(m_expirationTimePoint));
+
+  totalLength += prependNonNegativeIntegerBlock(encoder, ndn::tlv::nlsr::SequenceNumber,
+                                                m_seqNo);
+
+  totalLength += m_originRouter.wireEncode(encoder);
+
+  totalLength += encoder.prependVarNumber(totalLength);
+  totalLength += encoder.prependVarNumber(ndn::tlv::nlsr::Lsa);
+
+  return totalLength;
+}
+
+NDN_CXX_DEFINE_WIRE_ENCODE_INSTANTIATIONS(Lsa);
+
+void
+Lsa::wireDecode(const ndn::Block& wire)
+{
+  m_originRouter.clear();
+  m_seqNo = 0;
+
+  m_baseWire = wire;
+
+  if (m_baseWire.type() != ndn::tlv::nlsr::Lsa) {
+    std::stringstream error;
+    error << "Expected Lsa Block, but Block is of a different type: #"
+          << m_baseWire.type();
+    BOOST_THROW_EXCEPTION(Error(error.str()));
+  }
+
+  m_baseWire.parse();
+
+  ndn::Block::element_const_iterator val = m_baseWire.elements_begin();
+
+  if (val != m_baseWire.elements_end() && val->type() == ndn::tlv::Name) {
+    m_originRouter.wireDecode(*val);
+  }
+  else {
+    BOOST_THROW_EXCEPTION(Error("OriginRouter: Missing required Name field"));
+  }
+
+  ++val;
+
+  if (val != m_baseWire.elements_end() && val->type() == ndn::tlv::nlsr::SequenceNumber) {
+    m_seqNo = ndn::readNonNegativeInteger(*val);
+    ++val;
+  }
+  else {
+    BOOST_THROW_EXCEPTION(Error("Missing required SequenceNumber field"));
+  }
+
+  if (val != m_baseWire.elements_end() && val->type() == ndn::tlv::nlsr::ExpirationTime) {
+    m_expirationTimePoint = ndn::time::fromString(readString(*val));
+  }
+  else {
+    BOOST_THROW_EXCEPTION(Error("Missing required ExpirationTimePoint field"));
+  }
+}
+
+std::ostream&
+operator<<(std::ostream& os, const Lsa::Type& type)
+{
+  switch (type) {
+  case nlsr::Lsa::Type::ADJACENCY:
+    os << "ADJACENCY";
+    break;
+
+  case nlsr::Lsa::Type::COORDINATE:
+    os << "COORDINATE";
+    break;
+
+  case nlsr::Lsa::Type::NAME:
+    os << "NAME";
+    break;
+
+  default:
+    os << "BASE";
+    break;
+  }
+  return os;
+}
+
+std::istream&
+operator>>(std::istream& is, Lsa::Type& type)
+{
+  std::string typeString;
+  is >> typeString;
+  if (typeString == "ADJACENCY") {
+    type = Lsa::Type::ADJACENCY;
+  }
+  else if (typeString == "COORDINATE") {
+    type = Lsa::Type::COORDINATE;
+  }
+  else if (typeString == "NAME") {
+    type = Lsa::Type::NAME;
+  }
+  else {
+    type = Lsa::Type::BASE;
+  }
+  return is;
+}
+
+std::string
+Lsa::toString() const
+{
+  std::ostringstream os;
+  auto duration = getExpirationTimePoint() - ndn::time::system_clock::now();
+  os << "    " << getType() << " LSA:\n"
+     << "      Origin Router      : " << getOriginRouter() << "\n"
+     << "      Sequence Number    : " << getSeqNo() << "\n"
+     << "      Expires in         : " << ndn::time::duration_cast<ndn::time::milliseconds>(duration)
+     << "\n";
+  return os.str();
+}
+
+} // namespace nlsr