diff --git a/index.js b/index.js
index 5152fc5..fc3f414 100644
--- a/index.js
+++ b/index.js
@@ -14,8 +14,6 @@ var keepalive_interval = 60 * 1000;
 var last_message_hash = '';
 var log_level = 'info';
 
-var internal_ping_prefix = 'INTERNAL_PING.';
-
 if (config.globals.log_level) {
     log_level = config.globals.log_level;
 }
@@ -92,7 +90,7 @@ function onHttpIncomingMessage(request, response) {
     logger.info("onHttpIncomingMessage()", {qs: qs});
     
     // abaikan balikan ping
-    if (qs.to.match(internal_ping_prefix)) {
+    if (qs.to == config.globals.ping_ym_id) {
         return;
     }
     
@@ -134,8 +132,8 @@ function forwardMessageToEvo(sender, message, ts) {
         var pingOpts = {
             url: config.globals.evo_url,
             qs: {
-                msg: 'PING.' + message,
-                msisdn: internal_ping_prefix + msisdn,
+                msg: 'S.' + config.globals.ping_pin,
+                msisdn: config.globals.ping_ym_id + config.globals.msisdn_suffix,
                 smsc: config.globals.smsc,
                 ts: strftime('%F %T')
             }