diff --git a/datalink814_ge/src/linklayer/net_mgmt.c b/datalink814_ge/src/linklayer/net_mgmt.c
index f916d10..37bf63d 100644
--- a/datalink814_ge/src/linklayer/net_mgmt.c
+++ b/datalink814_ge/src/linklayer/net_mgmt.c
@@ -296,11 +296,11 @@ static int32_t MgmtMsg_Packing(L2_INST* instPtr, BIT_ARRAY* bitarr, L2_MSG_TYPE
 		dataChunk = 2;
 		FrameInsertChunk(bitarr, RTT_REQ_MSG_OFFSET, RTT_REQ_MSG_LEN, dataChunk);
 
-		// source node address length.
+		// source node address.
 		dataChunk = (L2_GetNodeId(instPtr) & 0x1F) | (((uint16_t)(L2_GetClusterId(instPtr) & 0x1F)) << 5);
 		FrameInsertChunk(bitarr, RTT_REQ_SRC_ADDR_OFFSET, RTT_REQ_SRC_ADDR_LEN, dataChunk);
 
-		// destination node address length.
+		// destination node address.
 		dataChunk = (0x02) | (((uint16_t) (L2_GetClusterId(instPtr) & 0x1F)) << 5);
 		FrameInsertChunk(bitarr, RTT_REQ_DST_ADDR_OFFSET, RTT_REQ_DST_ADDR_LEN, dataChunk);
 		break;
@@ -347,11 +347,11 @@ static int32_t MgmtMsg_Packing(L2_INST* instPtr, BIT_ARRAY* bitarr, L2_MSG_TYPE
 		dataChunk = 2;
 		FrameInsertChunk(bitarr, RTT_RSP_MSG_OFFSET, RTT_RSP_MSG_LEN, dataChunk);
 
-		// source node address length.
+		// source node address.
 		dataChunk = (L2_GetNodeId(instPtr) & 0x1F) | (((uint16_t)(L2_GetClusterId(instPtr) & 0x1F)) << 5);
 		FrameInsertChunk(bitarr, RTT_RSP_SRC_ADDR_OFFSET, RTT_RSP_SRC_ADDR_LEN, dataChunk);
 
-		// destination node address length.
+		// destination node address.
 		dataChunk = (0x01) | (((uint16_t) (L2_GetClusterId(instPtr) & 0x1F)) << 5);
 		FrameInsertChunk(bitarr, RTT_RSP_DST_ADDR_OFFSET, RTT_RSP_DST_ADDR_LEN, dataChunk);
 		break;
@@ -607,9 +607,11 @@ int32_t MgmtNet_PktHandler(L2_INST* instPtr) {
 	L2_RTT_MSG_RECORD *rttMsgRspLog = &(instPtr->mgmtNetFSM->rttMsgRspLog);
 	L2_RTT_MSG_RECORD *rttMsgReqLog = &(instPtr->mgmtNetFSM->rttMsgReqLog);
 
+	DBG_INFO("Management net handling packet...\n");
+
 	BIT_ARRAY* mgmtMsg = bit_array_create(L2_MSG_MAX);
 	if (mgmtMsg == NULL) {
-		free(mgmtMsg);
+		DBG_INFO("Failed to start handling process...\n");
 		return EALLOC;
 	}
 	switch (L2_GetLastFrameType(instPtr)) {
@@ -929,6 +931,7 @@ int32_t MgmtNet_Routine(L2_INST* instPtr, const L2_RTNE_TABLE_ENTRY* rtneEntry){
 			if(rttRxEvent == NULL) {
 				DBG_ERROR("Failed to initialize rtt event.\n");
 			}
+			// Schedule rtt update after receive process end.
 			Status = L2_ScheduleEventAfter(instPtr, rttRxEvent, INTRA_TSYNC_SLOTS + 1);
 		}
 	}
diff --git a/datalink814_ge/src/linklayer/net_scan.c b/datalink814_ge/src/linklayer/net_scan.c
index 938c2ed..5aef77b 100644
--- a/datalink814_ge/src/linklayer/net_scan.c
+++ b/datalink814_ge/src/linklayer/net_scan.c
@@ -573,9 +573,12 @@ int32_t ScanNet_PktHandler(L2_INST* instPtr) {
 	uint32_t Status;
 	L2_SCAN_FSM* scanFsmPtr = instPtr->scanNetFSM;
 	uint64_t dataChunk;
+
+	DBG_INFO("Scan net handling packet...\n");
+
 	BIT_ARRAY* scanMsg = bit_array_create(L2_MSG_MAX);
 	if (scanMsg == NULL) {
-		free(scanMsg);
+		DBG_INFO("Failed to start handling process...\n");
 		return EALLOC;
 	}
 	switch (L2_GetLastFrameType(instPtr)) {
diff --git a/datalink814_ge/src/linklayer/net_service.c b/datalink814_ge/src/linklayer/net_service.c
index 0345bcd..6add87b 100644
--- a/datalink814_ge/src/linklayer/net_service.c
+++ b/datalink814_ge/src/linklayer/net_service.c
@@ -205,6 +205,8 @@ void ServiceNet_Destroy(L2_SVC_FSM* serviceFSM){
  ******************************************************************************/
 int32_t ServiceNet_PktHandler(L2_INST* instPtr) {
 	// TODO:
+	DBG_INFO("Scan net handling packet...\n");
+
 	return SUCCESS;
 }
 
@@ -252,7 +254,7 @@ int32_t ServiceNet_Routine(L2_INST* instPtr, const L2_RTNE_TABLE_ENTRY* rtneEntr
 	case L2_SLOT_INTRA_SVC:
 		if(torState == L2_TOR_TX){
 			//TODO: 
-			memset(instPtr->sendPktData, 0xAA, INTRA_SVC_FRAME_LENGTH_MAX);
+			memset(instPtr->sendPktData, 0x00, INTRA_SVC_FRAME_LENGTH_MAX);
 			// Pack PDU header
 			if(PduHeader_Packing(instPtr, svcMsg, L2_PDU_HEADER_0, rtneEntry->dst0) != SUCCESS){
 				DBG_ERROR("Failed to packing PduHeader.\n");