diff --git a/tools/ping/server/main.cpp b/tools/ping/server/main.cpp
index e81125c..bf050da 100644
--- a/tools/ping/server/main.cpp
+++ b/tools/ping/server/main.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2015-2021, Arizona Board of Regents.
+ * Copyright (c) 2015-2022, Arizona Board of Regents.
  *
  * This file is part of ndn-tools (Named Data Networking Essential Tools).
  * See AUTHORS.md for complete list of ndn-tools authors and contributors.
@@ -31,9 +31,7 @@
 #include <boost/program_options/parsers.hpp>
 #include <boost/program_options/variables_map.hpp>
 
-namespace ndn {
-namespace ping {
-namespace server {
+namespace ndn::ping::server {
 
 namespace po = boost::program_options;
 
@@ -90,7 +88,7 @@
 };
 
 static void
-usage(std::ostream& os, const std::string& programName, const po::options_description& options)
+usage(std::ostream& os, std::string_view programName, const po::options_description& options)
 {
   os << "Usage: " << programName << " [options] <prefix>\n"
      << "\n"
@@ -187,9 +185,7 @@
   return Runner(options).run();
 }
 
-} // namespace server
-} // namespace ping
-} // namespace ndn
+} // namespace ndn::ping::server
 
 int
 main(int argc, char* argv[])
diff --git a/tools/ping/server/ping-server.cpp b/tools/ping/server/ping-server.cpp
index 5ceeb76..69093d3 100644
--- a/tools/ping/server/ping-server.cpp
+++ b/tools/ping/server/ping-server.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2015-2021,  Arizona Board of Regents.
+ * Copyright (c) 2015-2022,  Arizona Board of Regents.
  *
  * This file is part of ndn-tools (Named Data Networking Essential Tools).
  * See AUTHORS.md for complete list of ndn-tools authors and contributors.
@@ -24,15 +24,12 @@
 
 #include <ndn-cxx/security/signing-helpers.hpp>
 
-namespace ndn {
-namespace ping {
-namespace server {
+namespace ndn::ping::server {
 
 PingServer::PingServer(Face& face, KeyChain& keyChain, const Options& options)
   : m_options(options)
   , m_face(face)
   , m_keyChain(keyChain)
-  , m_nPings(0)
 {
   auto b = make_shared<Buffer>();
   b->assign(m_options.payloadSize, 'a');
@@ -78,6 +75,4 @@
   }
 }
 
-} // namespace server
-} // namespace ping
-} // namespace ndn
+} // namespace ndn::ping::server
diff --git a/tools/ping/server/ping-server.hpp b/tools/ping/server/ping-server.hpp
index f13769c..e9127c0 100644
--- a/tools/ping/server/ping-server.hpp
+++ b/tools/ping/server/ping-server.hpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2015-2021,  Arizona Board of Regents.
+ * Copyright (c) 2015-2022,  Arizona Board of Regents.
  *
  * This file is part of ndn-tools (Named Data Networking Essential Tools).
  * See AUTHORS.md for complete list of ndn-tools authors and contributors.
@@ -27,9 +27,7 @@
 
 #include <ndn-cxx/util/signal.hpp>
 
-namespace ndn {
-namespace ping {
-namespace server {
+namespace ndn::ping::server {
 
 /**
  * @brief Options for PingServer
@@ -105,13 +103,11 @@
   const Options& m_options;
   Face& m_face;
   KeyChain& m_keyChain;
-  size_t m_nPings;
+  size_t m_nPings = 0;
   Block m_payload;
   RegisteredPrefixHandle m_registeredPrefix;
 };
 
-} // namespace server
-} // namespace ping
-} // namespace ndn
+} // namespace ndn::ping::server
 
 #endif // NDN_TOOLS_PING_SERVER_PING_SERVER_HPP
diff --git a/tools/ping/server/tracer.cpp b/tools/ping/server/tracer.cpp
index c6b30b9..0a9df40 100644
--- a/tools/ping/server/tracer.cpp
+++ b/tools/ping/server/tracer.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2015-2021,  Arizona Board of Regents.
+ * Copyright (c) 2015-2022,  Arizona Board of Regents.
  *
  * This file is part of ndn-tools (Named Data Networking Essential Tools).
  * See AUTHORS.md for complete list of ndn-tools authors and contributors.
@@ -21,9 +21,7 @@
 
 #include "tracer.hpp"
 
-namespace ndn {
-namespace ping {
-namespace server {
+namespace ndn::ping::server {
 
 Tracer::Tracer(PingServer& pingServer, const Options& options)
   : m_options(options)
@@ -38,6 +36,4 @@
   }
 }
 
-} // namespace server
-} // namespace ping
-} // namespace ndn
+} // namespace ndn::ping::server
diff --git a/tools/ping/server/tracer.hpp b/tools/ping/server/tracer.hpp
index a84b72e..e8aac85 100644
--- a/tools/ping/server/tracer.hpp
+++ b/tools/ping/server/tracer.hpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2015-2021,  Arizona Board of Regents.
+ * Copyright (c) 2015-2022,  Arizona Board of Regents.
  *
  * This file is part of ndn-tools (Named Data Networking Essential Tools).
  * See AUTHORS.md for complete list of ndn-tools authors and contributors.
@@ -26,9 +26,7 @@
 
 #include "ping-server.hpp"
 
-namespace ndn {
-namespace ping {
-namespace server {
+namespace ndn::ping::server {
 
 /**
  * @brief Logs ping responses
@@ -42,8 +40,6 @@
   const Options& m_options;
 };
 
-} // namespace server
-} // namespace ping
-} // namespace ndn
+} // namespace ndn::ping::server
 
 #endif // NDN_TOOLS_PING_SERVER_TRACER_HPP