diff --git a/src/common.hpp b/src/common.hpp
index 317789c..ee122d3 100644
--- a/src/common.hpp
+++ b/src/common.hpp
@@ -43,6 +43,8 @@
 #include <list>
 #include <algorithm>
 #include <iostream>
+#include <functional>
+#include <memory>
 
 namespace repo {
 
@@ -58,13 +60,11 @@
 using ndn::Scheduler;
 using ndn::ValidatorConfig;
 
-using ndn::bind;
-using ndn::shared_ptr;
-using ndn::make_shared;
-using ndn::enable_shared_from_this;
-
-using std::vector;
-using std::string;
+using std::shared_ptr;
+using std::make_shared;
+using std::bind;
+using std::placeholders::_1;
+using std::placeholders::_2;
 
 using boost::noncopyable;
 
diff --git a/src/handles/base-handle.hpp b/src/handles/base-handle.hpp
index 44ac4a8..95b8caa 100644
--- a/src/handles/base-handle.hpp
+++ b/src/handles/base-handle.hpp
@@ -110,7 +110,7 @@
 inline void
 BaseHandle::reply(const Interest& commandInterest, const RepoCommandResponse& response)
 {
-  shared_ptr<Data> rdata = make_shared<Data>(commandInterest.getName());
+  std::shared_ptr<Data> rdata = std::make_shared<Data>(commandInterest.getName());
   rdata->setContent(response.wireEncode());
   m_keyChain.sign(*rdata);
   m_face.put(*rdata);
diff --git a/src/handles/delete-handle.cpp b/src/handles/delete-handle.cpp
index c6ad7c5..5cd0506 100644
--- a/src/handles/delete-handle.cpp
+++ b/src/handles/delete-handle.cpp
@@ -92,7 +92,8 @@
 }
 
 void
-DeleteHandle::onValidationFailed(const shared_ptr<const Interest>& interest, const string& reason)
+DeleteHandle::onValidationFailed(const shared_ptr<const Interest>& interest,
+                                 const std::string& reason)
 {
   std::cerr << reason << std::endl;
   negativeReply(*interest, 401);
diff --git a/src/handles/delete-handle.hpp b/src/handles/delete-handle.hpp
index 91ff244..5493d2e 100644
--- a/src/handles/delete-handle.hpp
+++ b/src/handles/delete-handle.hpp
@@ -25,8 +25,6 @@
 
 namespace repo {
 
-using std::vector;
-
 class DeleteHandle : public BaseHandle
 {
 
@@ -56,10 +54,10 @@
   onRegisterFailed(const Name& prefix, const std::string& reason);
 
   void
-  onValidated(const shared_ptr<const Interest>& interest, const Name& prefix);
+  onValidated(const std::shared_ptr<const Interest>& interest, const Name& prefix);
 
   void
-  onValidationFailed(const shared_ptr<const Interest>& interest, const string& reason);
+  onValidationFailed(const std::shared_ptr<const Interest>& interest, const std::string& reason);
 
   /**
    * @todo delete check has not been realized due to the while loop of segmented data deletion.
diff --git a/src/handles/tcp-bulk-insert-handle.hpp b/src/handles/tcp-bulk-insert-handle.hpp
index ef1cbdd..62ced11 100644
--- a/src/handles/tcp-bulk-insert-handle.hpp
+++ b/src/handles/tcp-bulk-insert-handle.hpp
@@ -59,7 +59,7 @@
 private:
   void
   handleAccept(const boost::system::error_code& error,
-               const shared_ptr<boost::asio::ip::tcp::socket>& socket);
+               const std::shared_ptr<boost::asio::ip::tcp::socket>& socket);
 
 private:
   boost::asio::ip::tcp::acceptor m_acceptor;
diff --git a/src/handles/watch-handle.cpp b/src/handles/watch-handle.cpp
index 15a82fa..9e80212 100644
--- a/src/handles/watch-handle.cpp
+++ b/src/handles/watch-handle.cpp
@@ -98,7 +98,8 @@
 }
 
 void
-WatchHandle::onValidationFailed(const shared_ptr<const Interest>& interest, const string& reason)
+WatchHandle::onValidationFailed(const shared_ptr<const Interest>& interest,
+                                const std::string& reason)
 {
   std::cerr << reason << std::endl;
   negativeReply(*interest, 401);
diff --git a/src/handles/watch-handle.hpp b/src/handles/watch-handle.hpp
index 10cddda..2fde3cf 100644
--- a/src/handles/watch-handle.hpp
+++ b/src/handles/watch-handle.hpp
@@ -71,10 +71,10 @@
   onInterest(const Name& prefix, const Interest& interest);
 
   void
-  onValidated(const shared_ptr<const Interest>& interest, const Name& prefix);
+  onValidated(const std::shared_ptr<const Interest>& interest, const Name& prefix);
 
   void
-  onValidationFailed(const shared_ptr<const Interest>& interest, const string& reason);
+  onValidationFailed(const std::shared_ptr<const Interest>& interest, const std::string& reason);
 
   void
   onRegistered(const Name& prefix);
@@ -96,14 +96,14 @@
   onTimeout(const Interest& interest, const Name& name);
 
   void
-  onDataValidated(const Interest& interest, const shared_ptr<const Data>& data,
+  onDataValidated(const Interest& interest, const std::shared_ptr<const Data>& data,
                   const Name& name);
 
   /**
    * @brief failure of validation
    */
   void
-  onDataValidationFailed(const Interest& interest, const shared_ptr<const Data>& data,
+  onDataValidationFailed(const Interest& interest, const std::shared_ptr<const Data>& data,
                          const std::string& reason, const Name& name);
 
 
@@ -121,10 +121,11 @@
   onCheckInterest(const Name& prefix, const Interest& interest);
 
   void
-  onCheckValidated(const shared_ptr<const Interest>& interest, const Name& prefix);
+  onCheckValidated(const std::shared_ptr<const Interest>& interest, const Name& prefix);
 
   void
-  onCheckValidationFailed(const shared_ptr<const Interest>& interest, const std::string& reason);
+  onCheckValidationFailed(const std::shared_ptr<const Interest>& interest,
+                          const std::string& reason);
 
 private: // watch stop command
   /**
@@ -134,10 +135,11 @@
   onStopInterest(const Name& prefix, const Interest& interest);
 
   void
-  onStopValidated(const shared_ptr<const Interest>& interest, const Name& prefix);
+  onStopValidated(const std::shared_ptr<const Interest>& interest, const Name& prefix);
 
   void
-  onStopValidationFailed(const shared_ptr<const Interest>& interest, const std::string& reason);
+  onStopValidationFailed(const std::shared_ptr<const Interest>& interest,
+                         const std::string& reason);
 
 private:
   void
diff --git a/src/handles/write-handle.cpp b/src/handles/write-handle.cpp
index 0bc4e12..08e951b 100644
--- a/src/handles/write-handle.cpp
+++ b/src/handles/write-handle.cpp
@@ -20,7 +20,6 @@
 #include "write-handle.hpp"
 
 namespace repo {
-using namespace ndn::time;
 
 static const int RETRY_TIMEOUT = 3;
 static const int DEFAULT_CREDIT = 12;
@@ -72,7 +71,7 @@
 }
 
 void
-WriteHandle::onValidated(const shared_ptr<const Interest>& interest, const Name& prefix)
+WriteHandle::onValidated(const std::shared_ptr<const Interest>& interest, const Name& prefix)
 {
   //m_validResult = 1;
   RepoCommandParameter parameter;
@@ -99,14 +98,15 @@
 }
 
 void
-WriteHandle::onValidationFailed(const shared_ptr<const Interest>& interest, const string& reason)
+WriteHandle::onValidationFailed(const std::shared_ptr<const Interest>& interest,
+                                const std::string& reason)
 {
   std::cerr << reason << std::endl;
   negativeReply(*interest, 401);
 }
 
 void
-WriteHandle::onData(const Interest& interest, ndn::Data& data, ProcessId processId)
+WriteHandle::onData(const Interest& interest, Data& data, ProcessId processId)
 {
   m_validator.validate(data,
                        bind(&WriteHandle::onDataValidated, this, interest, _1, processId),
@@ -114,7 +114,8 @@
 }
 
 void
-WriteHandle::onDataValidated(const Interest& interest, const shared_ptr<const Data>& data,
+WriteHandle::onDataValidated(const Interest& interest,
+                             const std::shared_ptr<const Data>& data,
                              ProcessId processId)
 {
   if (m_processes.count(processId) == 0) {
@@ -135,7 +136,8 @@
 }
 
 void
-WriteHandle::onDataValidationFailed(const shared_ptr<const Data>& data, const std::string& reason)
+WriteHandle::onDataValidationFailed(const std::shared_ptr<const Data>& data,
+                                    const std::string& reason)
 {
   std::cerr << reason << std::endl;
 }
@@ -150,7 +152,7 @@
 
 void
 WriteHandle::onSegmentDataValidated(const Interest& interest,
-                                    const shared_ptr<const Data>& data,
+                                    const std::shared_ptr<const Data>& data,
                                     ProcessId processId)
 {
   if (m_processes.count(processId) == 0) {
@@ -182,7 +184,7 @@
 }
 
 void
-WriteHandle::onTimeout(const ndn::Interest& interest, ProcessId processId)
+WriteHandle::onTimeout(const Interest& interest, ProcessId processId)
 {
   std::cerr << "Timeout" << std::endl;
   m_processes.erase(processId);
diff --git a/src/handles/write-handle.hpp b/src/handles/write-handle.hpp
index bbbfe28..1c64437 100644
--- a/src/handles/write-handle.hpp
+++ b/src/handles/write-handle.hpp
@@ -109,10 +109,10 @@
   onInterest(const Name& prefix, const Interest& interest);
 
   void
-  onValidated(const shared_ptr<const Interest>& interest, const Name& prefix);
+  onValidated(const std::shared_ptr<const Interest>& interest, const Name& prefix);
 
   void
-  onValidationFailed(const shared_ptr<const Interest>& interest, const string& reason);
+  onValidationFailed(const std::shared_ptr<const Interest>& interest, const std::string& reason);
 
   /**
    * @brief insert command prefix register failed
@@ -128,7 +128,7 @@
   onData(const Interest& interest, Data& data, ProcessId processId);
 
   void
-  onDataValidated(const Interest& interest, const shared_ptr<const Data>& data,
+  onDataValidated(const Interest& interest, const std::shared_ptr<const Data>& data,
                   ProcessId processId);
 
   /**
@@ -148,7 +148,7 @@
   onSegmentData(const Interest& interest, Data& data, ProcessId processId);
 
   void
-  onSegmentDataValidated(const Interest& interest, const shared_ptr<const Data>& data,
+  onSegmentDataValidated(const Interest& interest, const std::shared_ptr<const Data>& data,
                          ProcessId processId);
 
   /**
@@ -183,7 +183,7 @@
    * @brief failure of validation for both one or segmented data
    */
   void
-  onDataValidationFailed(const shared_ptr<const Data>& data, const std::string& reason);
+  onDataValidationFailed(const std::shared_ptr<const Data>& data, const std::string& reason);
 
   /**
    * @brief extends noEndTime of process if not noEndTimeout, set StatusCode 405
@@ -208,10 +208,11 @@
   onCheckRegisterFailed(const Name& prefix, const std::string& reason);
 
   void
-  onCheckValidated(const shared_ptr<const Interest>& interest, const Name& prefix);
+  onCheckValidated(const std::shared_ptr<const Interest>& interest, const Name& prefix);
 
   void
-  onCheckValidationFailed(const shared_ptr<const Interest>& interest, const std::string& reason);
+  onCheckValidationFailed(const std::shared_ptr<const Interest>& interest,
+                          const std::string& reason);
 
 private:
   void
diff --git a/src/main.cpp b/src/main.cpp
index 3a1be07..9713943 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -20,9 +20,7 @@
 #include "config.hpp"
 #include "repo.hpp"
 
-using namespace repo;
-
-static const string ndnRepoUsageMessage =
+static const std::string ndnRepoUsageMessage =
   /* argv[0] */ " - Next generation of NDN repository\n"
   "-h: show help message\n"
   "-c: set config file path\n"
@@ -46,15 +44,16 @@
   else
     {
       /// \todo May be try to reload config file
-      signalSet.async_wait(bind(&terminate, boost::ref(ioService), _1, _2,
-                                boost::ref(signalSet)));
+      signalSet.async_wait(std::bind(&terminate, std::ref(ioService),
+                                     std::placeholders::_1, std::placeholders::_2,
+                                     std::ref(signalSet)));
     }
 }
 
 int
 main(int argc, char** argv)
 {
-  string configPath = DEFAULT_CONFIG_FILE;
+  std::string configPath = DEFAULT_CONFIG_FILE;
   int opt;
   while ((opt = getopt(argc, argv, "hc:")) != -1) {
     switch (opt) {
@@ -62,7 +61,7 @@
       std::cout << argv[0] << ndnRepoUsageMessage << std::endl;
       return 1;
     case 'c':
-      configPath = string(optarg);
+      configPath = std::string(optarg);
       break;
     default:
       break;
@@ -71,7 +70,7 @@
 
   try {
     boost::asio::io_service ioService;
-    Repo repoInstance(ioService, parseConfig(configPath));
+    repo::Repo repoInstance(ioService, repo::parseConfig(configPath));
 
     boost::asio::signal_set signalSet(ioService);
     signalSet.add(SIGINT);
@@ -79,8 +78,9 @@
     signalSet.add(SIGHUP);
     signalSet.add(SIGUSR1);
     signalSet.add(SIGUSR2);
-    signalSet.async_wait(bind(&terminate, boost::ref(ioService), _1, _2,
-                              boost::ref(signalSet)));
+    signalSet.async_wait(std::bind(&terminate, std::ref(ioService),
+                                   std::placeholders::_1, std::placeholders::_2,
+                                   std::ref(signalSet)));
 
     repoInstance.initializeStorage();
 
diff --git a/src/repo.cpp b/src/repo.cpp
index 02c80da..64287e2 100644
--- a/src/repo.cpp
+++ b/src/repo.cpp
@@ -19,6 +19,7 @@
 
 #include "repo.hpp"
 #include "storage/sqlite-storage.hpp"
+
 namespace repo {
 
 RepoConfig
@@ -114,7 +115,7 @@
   : m_config(config)
   , m_scheduler(ioService)
   , m_face(ioService)
-  , m_store(make_shared<SqliteStorage>(config.dbPath))
+  , m_store(std::make_shared<SqliteStorage>(config.dbPath))
   , m_storageHandle(config.nMaxPackets, *m_store)
   , m_validator(m_face)
   , m_readHandle(m_face, m_storageHandle, m_keyChain, m_scheduler)
@@ -142,7 +143,7 @@
 Repo::enableListening()
 {
   // Enable "listening" on Data prefixes
-  for (vector<ndn::Name>::iterator it = m_config.dataPrefixes.begin();
+  for (auto it = m_config.dataPrefixes.begin();
        it != m_config.dataPrefixes.end();
        ++it)
     {
@@ -150,7 +151,7 @@
     }
 
   // Enable "listening" on control prefixes
-  for (vector<ndn::Name>::iterator it = m_config.repoPrefixes.begin();
+  for (auto it = m_config.repoPrefixes.begin();
        it != m_config.repoPrefixes.end();
        ++it)
     {
@@ -160,7 +161,7 @@
     }
 
   // Enable listening on TCP bulk insert addresses
-  for (vector<pair<string, string> >::iterator it = m_config.tcpBulkInsertEndpoints.begin();
+  for (auto it = m_config.tcpBulkInsertEndpoints.begin();
        it != m_config.tcpBulkInsertEndpoints.end();
        ++it)
     {
diff --git a/src/repo.hpp b/src/repo.hpp
index e1feea6..3e7e89d 100644
--- a/src/repo.hpp
+++ b/src/repo.hpp
@@ -37,18 +37,14 @@
 
 namespace repo {
 
-using std::string;
-using std::vector;
-using std::pair;
-
 struct RepoConfig
 {
-  string repoConfigPath;
+  std::string repoConfigPath;
   //StorageMethod storageMethod; This will be implemtented if there is other method.
   std::string dbPath;
-  vector<ndn::Name> dataPrefixes;
-  vector<ndn::Name> repoPrefixes;
-  vector<pair<string, string> > tcpBulkInsertEndpoints;
+  std::vector<ndn::Name> dataPrefixes;
+  std::vector<ndn::Name> repoPrefixes;
+  std::vector<std::pair<std::string, std::string> > tcpBulkInsertEndpoints;
   int64_t nMaxPackets;
   boost::property_tree::ptree validatorNode;
 };
@@ -86,7 +82,7 @@
   RepoConfig m_config;
   ndn::Scheduler m_scheduler;
   ndn::Face m_face;
-  shared_ptr<Storage> m_store;
+  std::shared_ptr<Storage> m_store;
   RepoStorage m_storageHandle;
   KeyChain m_keyChain;
   ValidatorConfig m_validator;
diff --git a/src/storage/repo-storage.hpp b/src/storage/repo-storage.hpp
index ed0ce9d..bc2ecbe 100644
--- a/src/storage/repo-storage.hpp
+++ b/src/storage/repo-storage.hpp
@@ -84,15 +84,14 @@
   /**
    *  @brief  read data from repo
    *  @param   interest  used to request data
-   *  @return  std::pair<bool,shared_ptr<Data> >
+   *  @return  std::shared_ptr<Data>
    */
-  shared_ptr<Data>
+  std::shared_ptr<Data>
   readData(const Interest& interest) const;
 
 private:
   Index m_index;
   Storage& m_storage;
-
 };
 
 } // namespace repo
diff --git a/src/storage/skiplist.hpp b/src/storage/skiplist.hpp
index 34c7c57..e6dd6a0 100644
--- a/src/storage/skiplist.hpp
+++ b/src/storage/skiplist.hpp
@@ -397,7 +397,7 @@
     m_head->prevs.resize(newLevel + 1, m_head);
     insertPositions.resize(newLevel + 1, m_head);
   }
-  for (int i = 0; i <= newLevel; i++) {
+  for (size_t i = 0; i <= newLevel; i++) {
     newNode->nexts[i] = insertPositions[i]->nexts[i];
     newNode->prevs[i] = insertPositions[i];
     insertPositions[i]->nexts[i] = newNode;
diff --git a/src/storage/sqlite-storage.cpp b/src/storage/sqlite-storage.cpp
index 78b1792..7edcda7 100644
--- a/src/storage/sqlite-storage.cpp
+++ b/src/storage/sqlite-storage.cpp
@@ -25,6 +25,8 @@
 
 namespace repo {
 
+using std::string;
+
 SqliteStorage::SqliteStorage(const string& dbPath)
   : m_size(0)
 {
diff --git a/src/storage/sqlite-storage.hpp b/src/storage/sqlite-storage.hpp
index 73579c7..168cc41 100755
--- a/src/storage/sqlite-storage.hpp
+++ b/src/storage/sqlite-storage.hpp
@@ -48,7 +48,7 @@
   };
 
   explicit
-  SqliteStorage(const string& dbPath);
+  SqliteStorage(const std::string& dbPath);
 
   virtual
   ~SqliteStorage();
@@ -72,7 +72,7 @@
    *  @brief  get the data from database
    *  @para   id   id number of each entry in the database, used to find the data
    */
-  virtual shared_ptr<Data>
+  virtual std::shared_ptr<Data>
   read(const int64_t id);
 
   /**
@@ -86,7 +86,7 @@
    *         insertItemToIndex to reubuild index from database
    */
   void
-  fullEnumerate(const ndn::function<void(const Storage::ItemMeta)>& f);
+  fullEnumerate(const std::function<void(const Storage::ItemMeta)>& f);
 
 private:
   void
@@ -94,7 +94,7 @@
 
 private:
   sqlite3* m_db;
-  string m_dbPath;
+  std::string m_dbPath;
   int64_t m_size;
 };
 
diff --git a/src/storage/storage.hpp b/src/storage/storage.hpp
index 04f366f..bf75306 100755
--- a/src/storage/storage.hpp
+++ b/src/storage/storage.hpp
@@ -76,7 +76,7 @@
    *  @brief  get the data from database
    *  @param  id   id number of each entry in the database, used to find the data
    */
-  virtual shared_ptr<Data>
+  virtual std::shared_ptr<Data>
   read(const int64_t id) = 0;
 
   /**
@@ -90,7 +90,7 @@
    *         insertItemToIndex to reubuild index from database
    */
   virtual void
-  fullEnumerate(const ndn::function<void(const Storage::ItemMeta)>& f) = 0;
+  fullEnumerate(const std::function<void(const Storage::ItemMeta)>& f) = 0;
 
 };