diff --git a/tests/unit/security/additional-description.t.cpp b/tests/unit/security/additional-description.t.cpp
index 56a9090..2779816 100644
--- a/tests/unit/security/additional-description.t.cpp
+++ b/tests/unit/security/additional-description.t.cpp
@@ -72,10 +72,7 @@
   it++;
   BOOST_CHECK(it == aDescription.end());
 
-  BOOST_CHECK_EQUAL_COLLECTIONS(aDescription.wireEncode().wire(),
-                                aDescription.wireEncode().wire() + aDescription.wireEncode().size(),
-                                DESC,
-                                DESC + sizeof(DESC));
+  BOOST_TEST(aDescription.wireEncode() == DESC, boost::test_tools::per_element());
 
   AdditionalDescription aDescription2(Block{DESC});
   BOOST_CHECK_EQUAL(aDescription2, aDescription);
diff --git a/tests/unit/security/detail/certificate-bundle-decoder.t.cpp b/tests/unit/security/detail/certificate-bundle-decoder.t.cpp
index 630aaec..1199994 100644
--- a/tests/unit/security/detail/certificate-bundle-decoder.t.cpp
+++ b/tests/unit/security/detail/certificate-bundle-decoder.t.cpp
@@ -99,7 +99,7 @@
 {
   // First segment contains first 250 bytes of cert1
   Data d;
-  d.setContent(make_span(certBlock1.wire(), 250));
+  d.setContent(make_span(certBlock1).first(250));
 
   // Second segment contains the rest of cert1 and the first 100 bytes of cert2
   auto buf = std::make_shared<Buffer>(certBlock1.begin() + 250, certBlock1.end());
diff --git a/tests/unit/security/pib/pib-data-fixture.cpp b/tests/unit/security/pib/pib-data-fixture.cpp
index 37e1e6d..4fb5e36 100644
--- a/tests/unit/security/pib/pib-data-fixture.cpp
+++ b/tests/unit/security/pib/pib-data-fixture.cpp
@@ -63,7 +63,7 @@
 
 //         EncodingBuffer buf;
 //         cert.wireEncode(buf, true);
-//         cert.setSignatureValue(tpm.sign(buf.buf(), buf.size(), keyName, DigestAlgorithm::SHA256));
+//         cert.setSignatureValue(tpm.sign({buf}, keyName, DigestAlgorithm::SHA256));
 
 //         printBytes(prefix + "_KEY" + to_string(keyId) + "_CERT" + to_string(certVersion),
 //                    cert.wireEncode());
@@ -72,18 +72,12 @@
 //   }
 
 //   static void
-//   printBytes(const std::string& name, const Block& block)
-//   {
-//     printBytes(name, make_span(block.wire(), block.size()));
-//   }
-
-//   static void
-//   printBytes(const std::string& name, span<const uint8_t> buf)
+//   printBytes(const std::string& name, span<const uint8_t> bytes)
 //   {
 //     std::cout << "\nconst uint8_t " << name << "[] = {\n"
 //               << "  ";
 
-//     std::string hex = toHex(buf);
+//     std::string hex = toHex(bytes);
 
 //     for (size_t i = 0; i < hex.size(); i++) {
 //       if (i > 0 && i % 40 == 0)
diff --git a/tests/unit/security/validation-policy-config.t.cpp b/tests/unit/security/validation-policy-config.t.cpp
index 32fbf01..83c6f52 100644
--- a/tests/unit/security/validation-policy-config.t.cpp
+++ b/tests/unit/security/validation-policy-config.t.cpp
@@ -247,7 +247,7 @@
     {
       using namespace ndn::security::transform;
       const auto& cert = this->identity.getDefaultKey().getDefaultCertificate().wireEncode();
-      bufferSource(make_span(cert.wire(), cert.size())) >> base64Encode(false) >> streamSink(os);
+      bufferSource(cert) >> base64Encode(false) >> streamSink(os);
     }
 
     this->policy.load(this->baseConfig + R"CONF(
diff --git a/tests/unit/security/validation-policy-simple-hierarchy.t.cpp b/tests/unit/security/validation-policy-simple-hierarchy.t.cpp
index d5734a8..70fb49e 100644
--- a/tests/unit/security/validation-policy-simple-hierarchy.t.cpp
+++ b/tests/unit/security/validation-policy-simple-hierarchy.t.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2013-2021 Regents of the University of California.
+ * Copyright (c) 2013-2022 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
  *
@@ -73,15 +73,15 @@
 
 BOOST_AUTO_TEST_CASE(NonKeyNameInsideLocator)
 {
-  // auto cert = identity.getDefaultKey().getDefaultCertificate().wireEncode();
-  // std::cerr << "Certificate idCert{\"" << toHex(cert.wire(), cert.size()) << "\"_block};" << std::endl;
+//  auto cert = identity.getDefaultKey().getDefaultCertificate().wireEncode();
+//  std::cerr << "Certificate idCert{\"" << toHex(cert) << "\"_block};" << std::endl;
 
-  // cert = subIdentity.getDefaultKey().getDefaultCertificate().wireEncode();
-  // std::cerr << "Certificate subIdCert{\"" << toHex(cert.wire(), cert.size()) << "\"_block};" << std::endl;
+//  cert = subIdentity.getDefaultKey().getDefaultCertificate().wireEncode();
+//  std::cerr << "Certificate subIdCert{\"" << toHex(cert) << "\"_block};" << std::endl;
 
-  // Data packet("/Security/ValidatorFixture/Sub1/Sub2/Packet");
-  // m_keyChain.sign(packet, signingByIdentity(subIdentity));
-  // std::cerr << "Data packet{\"" << toHex(packet.wireEncode().wire(), packet.wireEncode().size()) << "\"_block};" << std::endl;
+//  Data pkt("/Security/ValidatorFixture/Sub1/Sub2/Packet");
+//  m_keyChain.sign(pkt, signingByIdentity(subIdentity));
+//  std::cerr << "Data packet{\"" << toHex(pkt.wireEncode()) << "\"_block};" << std::endl;
 
   // These are hard-coded with a key locator that is the exact name of the certificate
   Certificate idCert{"06FD014C073C08085365637572697479081056616C696461746F724669787475726508034B455"
diff --git a/tests/unit/security/verification-helpers.t.cpp b/tests/unit/security/verification-helpers.t.cpp
index d15f8f2..79cc41c 100644
--- a/tests/unit/security/verification-helpers.t.cpp
+++ b/tests/unit/security/verification-helpers.t.cpp
@@ -48,10 +48,10 @@
 //     {"Sha256", signingWithSha256()}
 //   };
 
-//   auto print = [] (const std::string& name, const uint8_t* buf, size_t size) {
+//   auto print = [] (const std::string& name, span<const uint8_t> buf) {
 //     std::cout << "  const Block " + name + "{{\n    ";
 
-//     std::string hex = toHex({buf, size});
+//     std::string hex = toHex(buf);
 
 //     for (size_t i = 0; i < hex.size(); i++) {
 //       if (i > 0 && i % 32 == 0)
@@ -74,23 +74,22 @@
 //     std::cout << "  const std::string name = \"" << type << "\";\n";
 
 //     if (signingInfo.getSignerType() == SigningInfo::SIGNER_TYPE_ID) {
-//       print("cert", signingInfo.getPibIdentity().getDefaultKey().getDefaultCertificate().wireEncode().wire(),
-//             signingInfo.getPibIdentity().getDefaultKey().getDefaultCertificate().wireEncode().size());
+//       print("cert", signingInfo.getPibIdentity().getDefaultKey().getDefaultCertificate().wireEncode());
 //     }
 //     else {
-//       print("cert", nullptr, 0);
+//       print("cert", {});
 //     }
 //     std::cout << "\n";
 
 //     // Create data that can be verified by cert
 //     Data data(Name("/test/data").append(type));
 //     m_keyChain.sign(data, signingInfo);
-//     print("goodData", data.wireEncode().wire(), data.wireEncode().size());
+//     print("goodData", data.wireEncode());
 //     std::cout << "\n";
 
 //     // Create data that cannot be verified by cert
 //     m_keyChain.sign(data, signingByIdentity(wrongIdentity));
-//     print("badSigData", data.wireEncode().wire(), data.wireEncode().size());
+//     print("badSigData", data.wireEncode());
 //     std::cout << "\n";
 
 //     // Create interest that can be verified by cert
@@ -99,13 +98,13 @@
 //     signingInfoV03.setSignedInterestFormat(SignedInterestFormat::V03);
 //     interest1.setNonce(0xF72C8A4B);
 //     m_keyChain.sign(interest1, signingInfoV03);
-//     print("goodInterest", interest1.wireEncode().wire(), interest1.wireEncode().size());
+//     print("goodInterest", interest1.wireEncode());
 //     std::cout << "\n";
 
 //     // Create interest that cannot be verified by cert
 //     m_keyChain.sign(interest1, signingByIdentity(wrongIdentity)
 //                                  .setSignedInterestFormat(SignedInterestFormat::V03));
-//     print("badSigInterest", interest1.wireEncode().wire(), interest1.wireEncode().size());
+//     print("badSigInterest", interest1.wireEncode());
 //     std::cout << "\n";
 
 //     // Create interest that can be verified by cert (old signed Interest format)
@@ -114,13 +113,13 @@
 //     signingInfoV02.setSignedInterestFormat(SignedInterestFormat::V03);
 //     interest2.setNonce(0xF72C8A4B);
 //     m_keyChain.sign(interest2, signingInfoV02);
-//     print("goodInterestOldFormat", interest2.wireEncode().wire(), interest2.wireEncode().size());
+//     print("goodInterestOldFormat", interest2.wireEncode());
 //     std::cout << "\n";
 
 //     // Create interest that cannot be verified by cert (old signed Interest format)
 //     m_keyChain.sign(interest2, signingByIdentity(wrongIdentity)
 //                                  .setSignedInterestFormat(SignedInterestFormat::V02));
-//     print("badSigInterestOldFormat", interest2.wireEncode().wire(), interest2.wireEncode().size());
+//     print("badSigInterestOldFormat", interest2.wireEncode());
 //     std::cout << "\n};\n\n";
 //   }
 // }