diff --git a/src/client-config.cpp b/src/client-config.cpp
index 7fd5280..116e1d8 100644
--- a/src/client-config.cpp
+++ b/src/client-config.cpp
@@ -27,54 +27,42 @@
 void
 ClientConfig::load(const std::string& fileName)
 {
+  JsonSection config;
   try {
-    boost::property_tree::read_json(fileName, m_config);
+    boost::property_tree::read_json(fileName, config);
   }
   catch (const boost::property_tree::info_parser_error& error) {
     BOOST_THROW_EXCEPTION(Error("Failed to parse configuration file " + fileName +
                                 " " + error.message() + " line " + std::to_string(error.line())));
   }
 
-  if (m_config.begin() == m_config.end()) {
+  if (config.begin() == config.end()) {
     BOOST_THROW_EXCEPTION(Error("Error processing configuration file: " + fileName + " no data"));
   }
 
-  parse();
+  load(config);
 }
 
 void
-ClientConfig::parse()
+ClientConfig::load(const JsonSection& configSection)
 {
   m_caItems.clear();
-  auto caList = m_config.get_child("ca-list");
+  auto caList = configSection.get_child("ca-list");
   auto it = caList.begin();
   for (; it != caList.end(); it++) {
     ClientCaItem item;
     item.m_caName = Name(it->second.get<std::string>("ca-prefix"));
     item.m_caInfo = it->second.get<std::string>("ca-info");
     item.m_probe = it->second.get("probe", "");
+    item.m_targetedList = it->second.get("target-list", "");
 
     std::istringstream ss(it->second.get<std::string>("certificate"));
     item.m_anchor = *(io::load<security::v2::Certificate>(ss));
 
-    auto challengeList = it->second.get_child("supported-challenges");
-    item.m_supportedChallenges = parseChallengeList(challengeList);
-
     m_caItems.push_back(item);
   }
 }
 
-std::list<std::string>
-ClientConfig::parseChallengeList(const JsonSection& section)
-{
-  std::list<std::string> result;
-  auto it = section.begin();
-  for (; it != section.end(); it++) {
-    result.push_back(it->second.get<std::string>("type"));
-  }
-  return result;
-}
-
 void
 ClientConfig::addNewCaItem(const ClientCaItem& item)
 {
diff --git a/src/client-config.hpp b/src/client-config.hpp
index 8234c01..e32eab3 100644
--- a/src/client-config.hpp
+++ b/src/client-config.hpp
@@ -27,16 +27,33 @@
 namespace ndn {
 namespace ndncert {
 
+/**
+ * @brief The configuration for a trusted CA from a requester's perspective
+ */
 class ClientCaItem
 {
 public:
+  // The identity name of the CA. Extracted from config field "ca-prefix"
   Name m_caName;
+
+  // TODO: remove the caInfo, probe, and targetedList. Put them into the cert
+  // A brief introduction to the CA. Extracted from config field "ca-info"
   std::string m_caInfo;
+  // An instruction for requesters to use _PROBE. Extracted from config field "probe"
   std::string m_probe;
-  std::list<std::string> m_supportedChallenges;
+  // An instruction for requesters to get a recommended CA. Extracted from config field "target-list"
+  std::string m_targetedList;
+
+  // CA's certificate
   security::v2::Certificate m_anchor;
 };
 
+/**
+ * @brief Represents Client configuration
+ *
+ * For Client configuration format, please refer to:
+ *   https://github.com/named-data/ndncert/wiki/Client-Configuration-Sample
+ */
 class ClientConfig
 {
 public:
@@ -51,18 +68,14 @@
   load(const std::string& fileName);
 
   void
+  load(const JsonSection& configSection);
+
+  void
   addNewCaItem(const ClientCaItem& item);
 
   void
   removeCaItem(const Name& caName);
 
-PUBLIC_WITH_TESTS_ELSE_PRIVATE:
-  void
-  parse();
-
-  std::list<std::string>
-  parseChallengeList(const JsonSection& section);
-
 public:
   std::list<ClientCaItem> m_caItems;