diff --git a/src/security/nlsr_wl.cpp b/src/security/nlsr_wl.cpp
new file mode 100644
index 0000000..39ddfe3
--- /dev/null
+++ b/src/security/nlsr_wl.cpp
@@ -0,0 +1,75 @@
+#include <ndn-cpp-dev/face.hpp>
+#include "nlsr_wl.hpp"
+
+namespace nlsr
+{
+  static bool
+  waitingListCompare(const WaitingListEntry& w1, const std::string& respCert)
+  {
+    return w1.getResponsibleCert() == respCert;
+  }
+  
+  std::pair<WaitingListEntry, bool> 
+  WaitingList::getWaitingListEntry(std::string respCert)
+  {
+    std::list<WaitingListEntry>::iterator it = std::find_if( waitingTable.begin(),
+                waitingTable.end(),ndn::bind(&waitingListCompare, _1, respCert));
+    if( it != waitingTable.end() )
+    {
+      return std::make_pair(*(it),true);
+    }
+    
+    WaitingListEntry wle;
+    return std::make_pair(wle,false);
+    
+  }
+  
+  bool 
+  WaitingList::addtoWaitingList(std::string respCert, std::string waitee)
+  {
+    std::list<WaitingListEntry>::iterator it = std::find_if( waitingTable.begin(),
+                waitingTable.end(),ndn::bind(&waitingListCompare, _1, respCert));
+    if( it == waitingTable.end() )
+    {
+      WaitingListEntry newWle(respCert);
+      newWle.addWaitee(waitee);
+      waitingTable.push_back(newWle);
+      return true;
+    }
+    else
+    {
+      return it->addWaitee(waitee);
+    }
+    return false;
+  }
+  
+  bool 
+  WaitingList::removeFromWaitingList(std::string respCert)
+  {
+    std::list<WaitingListEntry>::iterator it = std::find_if( waitingTable.begin(),
+                waitingTable.end(),ndn::bind(&waitingListCompare, _1, respCert));
+    if( it == waitingTable.end() )
+    {
+      return false;
+    }
+    else
+    {
+      waitingTable.erase(it);
+      return true;
+    }
+    return false;
+  }
+  
+  std::ostream& 
+  operator<<(std::ostream& os, WaitingList wl)
+  {
+    os<<"-------Waiting List--------"<<std::endl;
+    std::list<WaitingListEntry> wles=wl.getWaitingTable();
+    for( std::list<WaitingListEntry> ::iterator it=wles.begin(); 
+                                                        it != wles.end(); ++it)
+    {
+      os<<*(it)<<std::endl;
+    }
+    return os;
+  }
+}