diff --git a/HISTORY b/HISTORY
index 8d108bd..4e2c206 100644
--- a/HISTORY
+++ b/HISTORY
@@ -1,6 +1,8 @@
 
-Version 1.22  2015-09-15
+Version 1.22  2015-10-09
   * export php function: fastcommon_get_first_local_ip
+  * add function is_private_ip
+  * add function get_next_local_ip
 
 Version 1.21  2015-09-14
   * ini_file_reader support annotation function
diff --git a/src/local_ip_func.c b/src/local_ip_func.c
index ecb17aa..068ec5a 100644
--- a/src/local_ip_func.c
+++ b/src/local_ip_func.c
@@ -134,26 +134,49 @@ void print_local_host_ip_addrs()
 	printf("\n");
 }
 
-const char *get_first_local_ip()
+const char *get_next_local_ip(const char *previous_ip)
 {
     char *p;
 	char *pEnd;
+    bool found;
 
     if (g_local_host_ip_count == 0)
     {
         load_local_host_ip_addrs();
     }
 
+    found = (previous_ip == NULL);
 	pEnd = g_local_host_ip_addrs + \
 		IP_ADDRESS_SIZE * g_local_host_ip_count;
 	for (p=g_local_host_ip_addrs; p<pEnd; p+=IP_ADDRESS_SIZE)
 	{
 	    if (strcmp(p, LOCAL_LOOPBACK_IP) != 0)
         {
-            return p;
+            if (found)
+            {
+                return p;
+            }
+            else if (strcmp(p, previous_ip) == 0)
+            {
+                found = true;
+            }
         }
 	}
 
-    return LOCAL_LOOPBACK_IP;
+    return NULL;
+}
+
+const char *get_first_local_ip()
+{
+    const char *first_ip;
+    first_ip = get_next_local_ip(NULL);
+    if (first_ip != NULL)
+    {
+        return first_ip;
+    }
+    else
+    {
+        return LOCAL_LOOPBACK_IP;
+    }
 }
 
diff --git a/src/local_ip_func.h b/src/local_ip_func.h
index 2ad328e..67ef721 100644
--- a/src/local_ip_func.h
+++ b/src/local_ip_func.h
@@ -31,7 +31,10 @@ extern char g_if_alias_prefix[FAST_IF_ALIAS_PREFIX_MAX_SIZE];
 
 void load_local_host_ip_addrs();
 bool is_local_host_ip(const char *client_ip);
+
 const char *get_first_local_ip();
+const char *get_next_local_ip(const char *previous_ip);
+
 int insert_into_local_host_ip(const char *client_ip);
 void log_local_host_ip_addrs();
 void print_local_host_ip_addrs();
diff --git a/src/shared_func.c b/src/shared_func.c
index b666841..c7caebb 100644
--- a/src/shared_func.c
+++ b/src/shared_func.c
@@ -2227,3 +2227,27 @@ double get_line_distance_km(const double lat1, const double lon1,
     return sqrt(lat_distance * lat_distance + lng_distance * lng_distance);
 }
 
+bool is_private_ip(const char* ip)
+{
+    if (ip == NULL || (int)strlen(ip) < 8)
+    {
+        return false;
+    }
+
+    if (memcmp(ip, "10.", 3) == 0 || memcmp(ip, "192.168.", 8) == 0)
+    {
+        return true;
+    }
+    if (memcmp(ip, "172.", 4) == 0)
+    {
+        int b;
+        b = atoi(ip + 4);
+        if (b >= 16 && b < 32)
+        {
+            return true;
+        }
+    }
+
+    return false;
+}
+
diff --git a/src/shared_func.h b/src/shared_func.h
index e88d90b..b9ee212 100644
--- a/src/shared_func.h
+++ b/src/shared_func.h
@@ -515,6 +515,11 @@ int ignore_signal_pipe();
 double get_line_distance_km(const double lat1, const double lon1,
         const double lat2, const double lon2);
 
+/** is private ip address for IPv4
+ *  return: true for private ip, otherwise false
+ */
+bool is_private_ip(const char* ip);
+
 #ifdef __cplusplus
 }
 #endif