diff --git a/libraries/esp8266/examples/NTP-TZ-DST/NTP-TZ-DST.ino b/libraries/esp8266/examples/NTP-TZ-DST/NTP-TZ-DST.ino
index ebfbd112b5..256301d95a 100644
--- a/libraries/esp8266/examples/NTP-TZ-DST/NTP-TZ-DST.ino
+++ b/libraries/esp8266/examples/NTP-TZ-DST/NTP-TZ-DST.ino
@@ -51,11 +51,7 @@
 #include <time.h>                       // time() ctime()
 #include <sys/time.h>                   // struct timeval
 
-#if LWIP_VERSION_MAJOR == 1
-#include <lwip/sntp.h>                  // sntp_servermode_dhcp()
-#else
-#include <lwip/apps/sntp.h>             // sntp_servermode_dhcp()
-#endif
+#include <sntp.h>                       // sntp_servermode_dhcp()
 
 // for testing purpose:
 extern "C" int clock_gettime(clockid_t unused, struct timespec *tp);
diff --git a/tools/sdk/include/sntp.h b/tools/sdk/include/sntp.h
index 4e842d7432..2947110571 100644
--- a/tools/sdk/include/sntp.h
+++ b/tools/sdk/include/sntp.h
@@ -5,11 +5,10 @@
 
 #include "lwip/init.h"
 #include "lwip/ip_addr.h"
-
 #if LWIP_VERSION_MAJOR == 1
-#define ipv4_addr_t ip_addr_t
+#include "lwip/sntp.h"
 #else
-typedef struct ip4_addr ipv4_addr_t;
+#include "lwip/apps/sntp.h"
 #endif
 
 #ifdef __cplusplus
@@ -32,48 +31,6 @@ sint8 sntp_get_timezone(void);
  * SNTP set time_zone (default GMT + 8)
  */
 bool sntp_set_timezone(sint8 timezone);
-/**
- * Initialize this module.
- * Send out request instantly or after SNTP_STARTUP_DELAY(_FUNC).
- */
-void sntp_init(void);
-/**
- * Stop this module.
- */
-void sntp_stop(void);
-/**
- * Initialize one of the NTP servers by IP address
- *
- * @param numdns the index of the NTP server to set must be < SNTP_MAX_SERVERS
- * @param dnsserver IP address of the NTP server to set
- */
-void sntp_setserver(unsigned char idx, ipv4_addr_t *addr);
-/**
- * Obtain one of the currently configured by IP address (or DHCP) NTP servers
- *
- * @param numdns the index of the NTP server
- * @return IP address of the indexed NTP server or "ipv4_addr_any" if the NTP
- *         server has not been configured by address (or at all).
- */
-ipv4_addr_t sntp_getserver(unsigned char idx);
-/**
- * Initialize one of the NTP servers by name
- *
- * @param numdns the index of the NTP server to set must be < SNTP_MAX_SERVERS,now sdk support SNTP_MAX_SERVERS = 3
- * @param dnsserver DNS name of the NTP server to set, to be resolved at contact time
- */
-void sntp_setservername(unsigned char idx, char *server);
-/**
- * Obtain one of the currently configured by name NTP servers.
- *
- * @param numdns the index of the NTP server
- * @return IP address of the indexed NTP server or NULL if the NTP
- *         server has not been configured by name (or at all)
- */
-char *sntp_getservername(unsigned char idx);
-
-#define sntp_servermode_dhcp(x)
-
 
 #ifdef __cplusplus
 }