diff --git a/components/aws_iot/port/network_mbedtls_wrapper.c b/components/aws_iot/port/network_mbedtls_wrapper.c
index 157c78f0..2b078da9 100644
--- a/components/aws_iot/port/network_mbedtls_wrapper.c
+++ b/components/aws_iot/port/network_mbedtls_wrapper.c
@@ -27,6 +27,7 @@
 #include "mbedtls/esp_debug.h"
 
 #include "esp_log.h"
+#include "esp_system.h"
 
 #ifdef CONFIG_USE_VFS
 #include "esp_vfs.h"
@@ -278,8 +279,12 @@ IoT_Error_t iot_tls_connect(Network *pNetwork, TLSConnectParams *params) {
 
     ESP_LOGD(TAG, "SSL state connect : %d ", tlsDataParams->ssl.state);
     ESP_LOGD(TAG, "Performing the SSL/TLS handshake...");
+
+    rtc_clk_cpu_freq_set(RTC_CPU_FREQ_160M);
+
     while((ret = mbedtls_ssl_handshake(&(tlsDataParams->ssl))) != 0) {
         if(ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE) {
+            rtc_clk_cpu_freq_set(RTC_CPU_FREQ_80M);
             ESP_LOGE(TAG, "failed! mbedtls_ssl_handshake returned -0x%x", -ret);
             if(ret == MBEDTLS_ERR_X509_CERT_VERIFY_FAILED) {
                 ESP_LOGE(TAG, "    Unable to verify the server's certificate. ");
@@ -288,6 +293,8 @@ IoT_Error_t iot_tls_connect(Network *pNetwork, TLSConnectParams *params) {
         }
     }
 
+    rtc_clk_cpu_freq_set(RTC_CPU_FREQ_80M);
+
     ESP_LOGD(TAG, "ok    [ Protocol is %s ]    [ Ciphersuite is %s ]", mbedtls_ssl_get_version(&(tlsDataParams->ssl)),
           mbedtls_ssl_get_ciphersuite(&(tlsDataParams->ssl)));
     if((ret = mbedtls_ssl_get_record_expansion(&(tlsDataParams->ssl))) >= 0) {
diff --git a/components/esp8266/lib/VERSION b/components/esp8266/lib/VERSION
index 28b27b06..4a992db5 100644
--- a/components/esp8266/lib/VERSION
+++ b/components/esp8266/lib/VERSION
@@ -1,5 +1,5 @@
 gwen:
-    core:       5ce569c
+    core:       25b7949
     net80211:   f7214eb
     pp:         cd2eae1
     wpa:        4e2372f
diff --git a/components/esp8266/lib/libcore.a b/components/esp8266/lib/libcore.a
index db3faeb3..c870943f 100644
Binary files a/components/esp8266/lib/libcore.a and b/components/esp8266/lib/libcore.a differ