diff --git a/Project/applications/smartcities/callbacks.c b/Project/applications/smartcities/callbacks.c
index c44fee6..9716f58 100644
--- a/Project/applications/smartcities/callbacks.c
+++ b/Project/applications/smartcities/callbacks.c
@@ -7,6 +7,7 @@ void dhcp_connect_result_cb(int result)
 	{
 		libwismart_GetCurrentIP(&ip,NULL,NULL);
 		printf("IP: %d.%d.%d.%d \r\n",ip.addr[3],ip.addr[2],ip.addr[1],ip.addr[0]);
+		connected = 1;
 	}
 	else if(result==LIBWISMART_DHCP_TIMEOUT)
 	{
diff --git a/Project/applications/smartcities/include/callbacks.h b/Project/applications/smartcities/include/callbacks.h
index 89b8ca1..d9e24fb 100644
--- a/Project/applications/smartcities/include/callbacks.h
+++ b/Project/applications/smartcities/include/callbacks.h
@@ -6,4 +6,6 @@
 void dhcp_connect_result_cb(int result);
 void wifi_connect_result_cb(int result);
 
+extern uint8_t connected;
+
 #endif
\ No newline at end of file
diff --git a/Project/applications/smartcities/include/json.h b/Project/applications/smartcities/include/json.h
index 1b472b3..f225f57 100644
--- a/Project/applications/smartcities/include/json.h
+++ b/Project/applications/smartcities/include/json.h
@@ -9,6 +9,7 @@
 #include <string.h>
 #include <stdio.h>
 #include "libwismart.h"
+#include "httpClient.h"
 
 #define	JSON_POST_OK		0
 #define	JSON_COMM_ERROR		1
@@ -17,7 +18,7 @@
 #define JOIN_NO_FREE		0
 #define JOIN_FREE_MEM		1
 
-char* prepare_json_statement(char** data, uint32_t nObservations);
+char* prepare_json_observation_statement(char** data, uint32_t nObservations);
 char* prepare_json_register_statement(module mod, sensor sens);
 char* prepare_observation(char* observation, uint32_t length);
 uint8_t send_json(char* statement, uint32_t length, char* provider_ID, char* sensor_ID);
diff --git a/Project/applications/smartcities/json.c b/Project/applications/smartcities/json.c
index 2285787..1ce006c 100644
--- a/Project/applications/smartcities/json.c
+++ b/Project/applications/smartcities/json.c
@@ -89,8 +89,7 @@ char* prepare_observation(char* observation, uint32_t length)
 uint8_t send_json(char* statement, uint32_t length, char* provider_ID, char* sensor_ID)
 {
 	int connectivity, response_code;
-	char* URL;
-	int server_hostname_length = strlen(SERVER_HOSTNAME);
+	char *URL, *PATH;
 	connectivity = libwismart_IsConnected();
 	if(connectivity != WISMART_CONNECTED)
 	{
@@ -98,32 +97,31 @@ uint8_t send_json(char* statement, uint32_t length, char* provider_ID, char* sen
 	}
 	if(sensor_ID == NULL) //Register sensor
 	{
-		URL = (char*) chHeapAlloc(NULL,17+server_hostname_length+strlen(provider_ID));
+		URL = (char*) chHeapAlloc(NULL,8+strlen(SERVER_HOSTNAME));
 		strcpy(URL,"http://");
 		strcpy(URL+7,SERVER_HOSTNAME);
-		strcpy(URL+7+server_hostname_length,"/catalog/");
-		strcpy(URL+16+server_hostname_length,provider_ID);
+		PATH = (char*) chHeapAlloc(NULL,10+strlen(provider_ID));
+		strcpy(PATH,"/catalog/");
+		strcpy(PATH+9,provider_ID);
 	}
 	else //Post data
 	{
-		URL = (char*) chHeapAlloc(NULL,18+server_hostname_length+strlen(provider_ID)+strlen(sensor_ID));
+		URL = (char*) chHeapAlloc(NULL,8+strlen(SERVER_HOSTNAME));
 		strcpy(URL,"http://");
 		strcpy(URL+7,SERVER_HOSTNAME);
-		strcpy(URL+7+server_hostname_length,"/data/");
-		strcpy(URL+16+server_hostname_length,provider_ID);
-		strcpy(URL+16+server_hostname_length+strlen(provider_ID),"/");
-		strcpy(URL+17+server_hostname_length+strlen(provider_ID),sensor_ID);
+		URL[7+strlen(SERVER_HOSTNAME)] = '\0';
+		PATH = (char*) chHeapAlloc(NULL,8+strlen(provider_ID)+strlen(sensor_ID));
+		strcpy(PATH,"/data/");
+		strcpy(PATH+6,provider_ID);
+		strcpy(PATH+6+strlen(provider_ID),sensor_ID);
+		PATH[7+strlen(provider_ID)+strlen(sensor_ID)] = '\0';
 	}
-
-	/* SELF-REMINDER
-	 *
-	 * Cambiar esto pa usar la función de Ferràn
-	 *
-	 * --Imanol
-	 */
-
-	//response_code = http_post(URL,statement,URL_length,length);
-	response_code = 200; //placeholder
+	printf("%s: %d\n\r",PATH,strlen(PATH));
+	printf("%s: %d\n\r",URL,strlen(URL));
+	struct httpHeaders server = { put,PATH,strlen(PATH),URL,strlen(URL)};
+	response_code = httpRequest(server, statement, length);
+	chHeapFree(PATH);
+	chHeapFree(URL);
 	if(response_code == 200)
 	{
 		return JSON_POST_OK;
@@ -159,11 +157,8 @@ char* join_strings(char* str1, char* str2, uint32_t len1, uint32_t len2, uint8_t
 	strncat(str,str2,len2);
 	if(free_mem)
 	{
-		free(str1);
-		free(str2);
+		chHeapFree(str1);
+		chHeapFree(str2);
 	}
 	return str; 
-}
-
-//check if exists
-//subscribe
\ No newline at end of file
+}
\ No newline at end of file