diff --git a/tests/unit-tests/requester.t.cpp b/tests/unit-tests/requester.t.cpp
new file mode 100644
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+++ b/tests/unit-tests/requester.t.cpp
@@ -0,0 +1,90 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2017-2020, Regents of the University of California.
+ *
+ * This file is part of ndncert, a certificate management system based on NDN.
+ *
+ * ndncert 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.
+ *
+ * ndncert 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 copies of the GNU General Public License along with
+ * ndncert, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * See AUTHORS.md for complete list of ndncert authors and contributors.
+ */
+
+#include <protocol-detail/error.hpp>
+#include "requester.hpp"
+#include "challenge-module.hpp"
+#include "ca-module.hpp"
+#include "test-common.hpp"
+
+namespace ndn {
+namespace ndncert {
+namespace tests {
+
+BOOST_FIXTURE_TEST_SUITE(TestRequester, IdentityManagementTimeFixture)
+
+/* PROBE */
+BOOST_AUTO_TEST_CASE(GenProbeInterest)
+{
+  auto identity = addIdentity(Name("/site"));
+  auto key = identity.getDefaultKey();
+  auto cert = key.getDefaultCertificate();
+
+  CaProfile ca_profile;
+  ca_profile.m_probeParameterKeys.push_back("email");
+  ca_profile.m_probeParameterKeys.push_back("uid");	
+  ca_profile.m_probeParameterKeys.push_back("name");
+  ca_profile.m_caPrefix = Name("/site");
+  ca_profile.m_cert = std::make_shared<security::v2::Certificate>(cert);
+
+  std::vector<std::tuple<std::string, std::string>> probeParams;
+  probeParams.push_back(std::make_tuple("email", "zhiyi@cs.ucla.edu"));
+  probeParams.push_back(std::make_tuple("uid", "987654321"));
+  probeParams.push_back(std::make_tuple("name", "Zhiyi Zhang"));
+  auto firstInterest = Requester::genProbeInterest(ca_profile, probeParams);
+
+  BOOST_CHECK(firstInterest->getName().at(-1).isParametersSha256Digest());
+  // ignore the last name component (ParametersSha256Digest)
+  BOOST_CHECK_EQUAL(firstInterest->getName().getPrefix(-1), "/site/CA/PROBE");		
+  BOOST_CHECK_EQUAL(readString(firstInterest->getApplicationParameters().get(tlv_parameter_value)), "zhiyi@cs.ucla.edu");
+}
+
+BOOST_AUTO_TEST_CASE(OnProbeResponse){}
+
+BOOST_AUTO_TEST_CASE(OnProbeResponseProbeRedirection){}
+
+BOOST_AUTO_TEST_CASE(ErrorHandling)
+{
+  auto identity = addIdentity(Name("/site"));
+  auto key = identity.getDefaultKey();
+  auto cert = key.getDefaultCertificate();
+
+  CaProfile item;
+  item.m_caPrefix = Name("/site");
+  item.m_cert = std::make_shared<security::v2::Certificate>(cert);
+  RequesterState state(m_keyChain, item, RequestType::NEW);
+
+  Data errorPacket;
+  errorPacket.setName(Name("/site/pretend/this/is/error/packet"));
+  errorPacket.setFreshnessPeriod(time::seconds(100));
+  errorPacket.setContent(ErrorTLV::encodeDataContent(ErrorCode::INVALID_PARAMETER, "This is a test."));
+  m_keyChain.sign(errorPacket, signingByIdentity(identity));
+
+  std::vector<Name> ids, cas;
+  BOOST_CHECK_THROW(Requester::onProbeResponse(errorPacket, item, ids, cas), std::runtime_error);
+  BOOST_CHECK_THROW(Requester::onNewRenewRevokeResponse(state, errorPacket), std::runtime_error);
+  BOOST_CHECK_THROW(Requester::onChallengeResponse(state, errorPacket), std::runtime_error);
+}
+
+BOOST_AUTO_TEST_SUITE_END() // TestRequester
+
+} // namespace tests
+} // namespace ndncert
+} // namespace ndn