diff --git a/components/mqtt/CMakeLists.txt b/components/mqtt/CMakeLists.txt
index 1c30e3a9..8f87ad74 100644
--- a/components/mqtt/CMakeLists.txt
+++ b/components/mqtt/CMakeLists.txt
@@ -4,4 +4,4 @@ idf_component_register(SRCS "esp-mqtt/mqtt_client.c"
                             "esp-mqtt/lib/platform_esp32_idf.c"
                     INCLUDE_DIRS esp-mqtt/include
                     PRIV_INCLUDE_DIRS "esp-mqtt/lib/include"
-                    REQUIRES lwip nghttp mbedtls tcp_transport)
+                    REQUIRES lwip http_parser mbedtls tcp_transport)
diff --git a/examples/protocols/mqtt/ssl/main/app_main.c b/examples/protocols/mqtt/ssl/main/app_main.c
index 1afb9c0b..24af8ca8 100644
--- a/examples/protocols/mqtt/ssl/main/app_main.c
+++ b/examples/protocols/mqtt/ssl/main/app_main.c
@@ -32,20 +32,6 @@ extern const uint8_t mqtt_eclipse_org_pem_start[]   asm("_binary_mqtt_eclipse_or
 #endif
 extern const uint8_t mqtt_eclipse_org_pem_end[]   asm("_binary_mqtt_eclipse_org_pem_end");
 
-//
-// Note: this function is for testing purposes only publishing the entire active partition
-//       (to be checked against the original binary)
-//
-static void send_binary(esp_mqtt_client_handle_t client)
-{
-    spi_flash_mmap_handle_t out_handle;
-    const void *binary_address;
-    const esp_partition_t* partition = esp_ota_get_running_partition();
-    esp_partition_mmap(partition, 0, partition->size, SPI_FLASH_MMAP_DATA, &binary_address, &out_handle);
-    int msg_id = esp_mqtt_client_publish(client, "/topic/binary", binary_address, partition->size, 0, 0);
-    ESP_LOGI(TAG, "binary sent with msg_id=%d", msg_id);
-}
-
 static esp_err_t mqtt_event_handler_cb(esp_mqtt_event_handle_t event)
 {
     esp_mqtt_client_handle_t client = event->client;
@@ -82,10 +68,6 @@ static esp_err_t mqtt_event_handler_cb(esp_mqtt_event_handle_t event)
             ESP_LOGI(TAG, "MQTT_EVENT_DATA");
             printf("TOPIC=%.*s\r\n", event->topic_len, event->topic);
             printf("DATA=%.*s\r\n", event->data_len, event->data);
-            if (strncmp(event->data, "send binary please", event->data_len) == 0) {
-                ESP_LOGI(TAG, "Sending the binary");
-                send_binary(client);
-            }
             break;
         case MQTT_EVENT_ERROR:
             ESP_LOGI(TAG, "MQTT_EVENT_ERROR");
diff --git a/examples/protocols/mqtt/ssl_psk/README.md b/examples/protocols/mqtt/ssl_psk/README.md
index c46688f0..c71a9219 100644
--- a/examples/protocols/mqtt/ssl_psk/README.md
+++ b/examples/protocols/mqtt/ssl_psk/README.md
@@ -6,6 +6,20 @@ This example connects to a local broker configured to PSK authentication
 
 ## How to use example
 
+### Code prepare
+
+If want to use psk function, maybe need change IDF version beyond v4.1 in `esp_idf_version.h`. Like this :
+```
+/** Major version number (X.x.x) */
+#define ESP_IDF_VERSION_MAJOR   4
+/** Minor version number (x.X.x) */
+#define ESP_IDF_VERSION_MINOR   2
+/** Patch version number (x.x.X) */
+#define ESP_IDF_VERSION_PATCH   0
+```
+
+This feature is controled by macro `MQTT_SUPPORTED_FEATURE_PSK_AUTHENTICATION`, defined in `mqtt_supported_features.h`.
+
 ### Hardware Required
 
 This example can be executed on any ESP32 board, the only required interface is WiFi (or ethernet) to connect to a MQTT