diff --git a/examples/server_example1/static_model.c b/examples/server_example1/static_model.c
index 3abfe08..a5f5dcf 100644
--- a/examples/server_example1/static_model.c
+++ b/examples/server_example1/static_model.c
@@ -149,6 +149,7 @@ extern DataSetEntry ds_Device1_LLN0_dataset1_fcda2;
 
 DataSetEntry ds_Device1_LLN0_dataset1_fcda0 = {
   "Device1",
+  false,
   "LLN0$ST$Mod$q",
   -1,
   NULL,
@@ -158,6 +159,7 @@ DataSetEntry ds_Device1_LLN0_dataset1_fcda0 = {
 
 DataSetEntry ds_Device1_LLN0_dataset1_fcda1 = {
   "Device1",
+  false,
   "MMXU1$ST$Mod$q",
   -1,
   NULL,
@@ -167,6 +169,7 @@ DataSetEntry ds_Device1_LLN0_dataset1_fcda1 = {
 
 DataSetEntry ds_Device1_LLN0_dataset1_fcda2 = {
   "Device1",
+  false,
   "MMXU1$CF$Mod$ctlModel",
   -1,
   NULL,
diff --git a/examples/server_example2/static_model.c b/examples/server_example2/static_model.c
index fbc3cfa..a483753 100644
--- a/examples/server_example2/static_model.c
+++ b/examples/server_example2/static_model.c
@@ -315,6 +315,7 @@ extern DataSetEntry ds_Inverter_LLN0_dataset1_fcda4;
 
 DataSetEntry ds_Inverter_LLN0_dataset1_fcda0 = {
   "Inverter",
+  false,
   "LLN0$ST$Mod$q",
   -1,
   NULL,
@@ -324,6 +325,7 @@ DataSetEntry ds_Inverter_LLN0_dataset1_fcda0 = {
 
 DataSetEntry ds_Inverter_LLN0_dataset1_fcda1 = {
   "Battery",
+  false,
   "LLN0$ST$Mod$q",
   -1,
   NULL,
@@ -333,6 +335,7 @@ DataSetEntry ds_Inverter_LLN0_dataset1_fcda1 = {
 
 DataSetEntry ds_Inverter_LLN0_dataset1_fcda2 = {
   "Inverter",
+  false,
   "MMXU1$ST$Mod$q",
   -1,
   NULL,
@@ -342,6 +345,7 @@ DataSetEntry ds_Inverter_LLN0_dataset1_fcda2 = {
 
 DataSetEntry ds_Inverter_LLN0_dataset1_fcda3 = {
   "Inverter",
+  false,
   "MMXU1$CF$Mod$ctlModel",
   -1,
   NULL,
@@ -351,6 +355,7 @@ DataSetEntry ds_Inverter_LLN0_dataset1_fcda3 = {
 
 DataSetEntry ds_Inverter_LLN0_dataset1_fcda4 = {
   "Inverter",
+  false,
   "MMXU1$MX$TotW$mag",
   -1,
   NULL,
diff --git a/examples/server_example3/static_model.c b/examples/server_example3/static_model.c
index 90a4eb5..eb1941b 100644
--- a/examples/server_example3/static_model.c
+++ b/examples/server_example3/static_model.c
@@ -162,6 +162,7 @@ extern DataSetEntry ds_GenericIO_LLN0_Events_fcda3;
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda0 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO1$stVal",
   -1,
   NULL,
@@ -171,6 +172,7 @@ DataSetEntry ds_GenericIO_LLN0_Events_fcda0 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda1 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO2$stVal",
   -1,
   NULL,
@@ -180,6 +182,7 @@ DataSetEntry ds_GenericIO_LLN0_Events_fcda1 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda2 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO3$stVal",
   -1,
   NULL,
@@ -189,6 +192,7 @@ DataSetEntry ds_GenericIO_LLN0_Events_fcda2 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda3 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO4$stVal",
   -1,
   NULL,
@@ -211,6 +215,7 @@ extern DataSetEntry ds_GenericIO_LLN0_Events2_fcda3;
 
 DataSetEntry ds_GenericIO_LLN0_Events2_fcda0 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO1",
   -1,
   NULL,
@@ -220,6 +225,7 @@ DataSetEntry ds_GenericIO_LLN0_Events2_fcda0 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events2_fcda1 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO2",
   -1,
   NULL,
@@ -229,6 +235,7 @@ DataSetEntry ds_GenericIO_LLN0_Events2_fcda1 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events2_fcda2 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO3",
   -1,
   NULL,
@@ -238,6 +245,7 @@ DataSetEntry ds_GenericIO_LLN0_Events2_fcda2 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events2_fcda3 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO4",
   -1,
   NULL,
@@ -264,6 +272,7 @@ extern DataSetEntry ds_GenericIO_LLN0_Measurements_fcda7;
 
 DataSetEntry ds_GenericIO_LLN0_Measurements_fcda0 = {
   "GenericIO",
+  false,
   "GGIO1$MX$AnIn1$mag$f",
   -1,
   NULL,
@@ -273,6 +282,7 @@ DataSetEntry ds_GenericIO_LLN0_Measurements_fcda0 = {
 
 DataSetEntry ds_GenericIO_LLN0_Measurements_fcda1 = {
   "GenericIO",
+  false,
   "GGIO1$MX$AnIn1$q",
   -1,
   NULL,
@@ -282,6 +292,7 @@ DataSetEntry ds_GenericIO_LLN0_Measurements_fcda1 = {
 
 DataSetEntry ds_GenericIO_LLN0_Measurements_fcda2 = {
   "GenericIO",
+  false,
   "GGIO1$MX$AnIn2$mag$f",
   -1,
   NULL,
@@ -291,6 +302,7 @@ DataSetEntry ds_GenericIO_LLN0_Measurements_fcda2 = {
 
 DataSetEntry ds_GenericIO_LLN0_Measurements_fcda3 = {
   "GenericIO",
+  false,
   "GGIO1$MX$AnIn2$q",
   -1,
   NULL,
@@ -300,6 +312,7 @@ DataSetEntry ds_GenericIO_LLN0_Measurements_fcda3 = {
 
 DataSetEntry ds_GenericIO_LLN0_Measurements_fcda4 = {
   "GenericIO",
+  false,
   "GGIO1$MX$AnIn3$mag$f",
   -1,
   NULL,
@@ -309,6 +322,7 @@ DataSetEntry ds_GenericIO_LLN0_Measurements_fcda4 = {
 
 DataSetEntry ds_GenericIO_LLN0_Measurements_fcda5 = {
   "GenericIO",
+  false,
   "GGIO1$MX$AnIn3$q",
   -1,
   NULL,
@@ -318,6 +332,7 @@ DataSetEntry ds_GenericIO_LLN0_Measurements_fcda5 = {
 
 DataSetEntry ds_GenericIO_LLN0_Measurements_fcda6 = {
   "GenericIO",
+  false,
   "GGIO1$MX$AnIn4$mag$f",
   -1,
   NULL,
@@ -327,6 +342,7 @@ DataSetEntry ds_GenericIO_LLN0_Measurements_fcda6 = {
 
 DataSetEntry ds_GenericIO_LLN0_Measurements_fcda7 = {
   "GenericIO",
+  false,
   "GGIO1$MX$AnIn4$q",
   -1,
   NULL,
diff --git a/examples/server_example4/static_model.c b/examples/server_example4/static_model.c
index 0897448..6bee7ce 100644
--- a/examples/server_example4/static_model.c
+++ b/examples/server_example4/static_model.c
@@ -159,6 +159,7 @@ extern DataSetEntry ds_GenericIO_LLN0_Events_fcda3;
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda0 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO1$stVal",
   -1,
   NULL,
@@ -168,6 +169,7 @@ DataSetEntry ds_GenericIO_LLN0_Events_fcda0 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda1 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO2$stVal",
   -1,
   NULL,
@@ -177,6 +179,7 @@ DataSetEntry ds_GenericIO_LLN0_Events_fcda1 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda2 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO3$stVal",
   -1,
   NULL,
@@ -186,6 +189,7 @@ DataSetEntry ds_GenericIO_LLN0_Events_fcda2 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda3 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO4$stVal",
   -1,
   NULL,
diff --git a/examples/server_example5/static_model.c b/examples/server_example5/static_model.c
index 0897448..6bee7ce 100644
--- a/examples/server_example5/static_model.c
+++ b/examples/server_example5/static_model.c
@@ -159,6 +159,7 @@ extern DataSetEntry ds_GenericIO_LLN0_Events_fcda3;
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda0 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO1$stVal",
   -1,
   NULL,
@@ -168,6 +169,7 @@ DataSetEntry ds_GenericIO_LLN0_Events_fcda0 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda1 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO2$stVal",
   -1,
   NULL,
@@ -177,6 +179,7 @@ DataSetEntry ds_GenericIO_LLN0_Events_fcda1 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda2 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO3$stVal",
   -1,
   NULL,
@@ -186,6 +189,7 @@ DataSetEntry ds_GenericIO_LLN0_Events_fcda2 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda3 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO4$stVal",
   -1,
   NULL,
diff --git a/examples/server_example_goose/static_model.c b/examples/server_example_goose/static_model.c
index 2beaeac..e1bcf92 100644
--- a/examples/server_example_goose/static_model.c
+++ b/examples/server_example_goose/static_model.c
@@ -160,6 +160,7 @@ extern DataSetEntry ds_GenericIO_LLN0_Events_fcda3;
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda0 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO1$stVal",
   -1,
   NULL,
@@ -169,6 +170,7 @@ DataSetEntry ds_GenericIO_LLN0_Events_fcda0 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda1 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO2$stVal",
   -1,
   NULL,
@@ -178,6 +180,7 @@ DataSetEntry ds_GenericIO_LLN0_Events_fcda1 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda2 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO3$stVal",
   -1,
   NULL,
@@ -187,6 +190,7 @@ DataSetEntry ds_GenericIO_LLN0_Events_fcda2 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda3 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO4$stVal",
   -1,
   NULL,
@@ -209,6 +213,7 @@ extern DataSetEntry ds_GenericIO_LLN0_AnalogValues_fcda3;
 
 DataSetEntry ds_GenericIO_LLN0_AnalogValues_fcda0 = {
   "GenericIO",
+  false,
   "GGIO1$MX$AnIn1",
   -1,
   NULL,
@@ -218,6 +223,7 @@ DataSetEntry ds_GenericIO_LLN0_AnalogValues_fcda0 = {
 
 DataSetEntry ds_GenericIO_LLN0_AnalogValues_fcda1 = {
   "GenericIO",
+  false,
   "GGIO1$MX$AnIn2",
   -1,
   NULL,
@@ -227,6 +233,7 @@ DataSetEntry ds_GenericIO_LLN0_AnalogValues_fcda1 = {
 
 DataSetEntry ds_GenericIO_LLN0_AnalogValues_fcda2 = {
   "GenericIO",
+  false,
   "GGIO1$MX$AnIn3",
   -1,
   NULL,
@@ -236,6 +243,7 @@ DataSetEntry ds_GenericIO_LLN0_AnalogValues_fcda2 = {
 
 DataSetEntry ds_GenericIO_LLN0_AnalogValues_fcda3 = {
   "GenericIO",
+  false,
   "GGIO1$MX$AnIn4",
   -1,
   NULL,
diff --git a/examples/server_example_threadless/static_model.c b/examples/server_example_threadless/static_model.c
index 9001748..f63c227 100644
--- a/examples/server_example_threadless/static_model.c
+++ b/examples/server_example_threadless/static_model.c
@@ -161,6 +161,7 @@ extern DataSetEntry ds_GenericIO_LLN0_Events_fcda3;
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda0 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO1$stVal",
   -1,
   NULL,
@@ -170,6 +171,7 @@ DataSetEntry ds_GenericIO_LLN0_Events_fcda0 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda1 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO2$stVal",
   -1,
   NULL,
@@ -179,6 +181,7 @@ DataSetEntry ds_GenericIO_LLN0_Events_fcda1 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda2 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO3$stVal",
   -1,
   NULL,
@@ -188,6 +191,7 @@ DataSetEntry ds_GenericIO_LLN0_Events_fcda2 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events_fcda3 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO4$stVal",
   -1,
   NULL,
@@ -210,6 +214,7 @@ extern DataSetEntry ds_GenericIO_LLN0_Events2_fcda3;
 
 DataSetEntry ds_GenericIO_LLN0_Events2_fcda0 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO1",
   -1,
   NULL,
@@ -219,6 +224,7 @@ DataSetEntry ds_GenericIO_LLN0_Events2_fcda0 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events2_fcda1 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO2",
   -1,
   NULL,
@@ -228,6 +234,7 @@ DataSetEntry ds_GenericIO_LLN0_Events2_fcda1 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events2_fcda2 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO3",
   -1,
   NULL,
@@ -237,6 +244,7 @@ DataSetEntry ds_GenericIO_LLN0_Events2_fcda2 = {
 
 DataSetEntry ds_GenericIO_LLN0_Events2_fcda3 = {
   "GenericIO",
+  false,
   "GGIO1$ST$SPCSO4",
   -1,
   NULL,
diff --git a/src/iec61850/client/client_control.c b/src/iec61850/client/client_control.c
index dc662a8..ff8c346 100644
--- a/src/iec61850/client/client_control.c
+++ b/src/iec61850/client/client_control.c
@@ -65,7 +65,7 @@ struct sControlObjectClient
 };
 
 static void
-convertToMmsAndInsertFC(char* newItemId, char* originalObjectName, char* fc)
+convertToMmsAndInsertFC(char* newItemId, const char* originalObjectName, const char* fc)
 {
     int originalLength = strlen(originalObjectName);
 
@@ -106,7 +106,7 @@ resetLastApplError(ControlObjectClient self)
 }
 
 ControlObjectClient
-ControlObjectClient_create(char* objectReference, IedConnection connection)
+ControlObjectClient_create(const char* objectReference, IedConnection connection)
 {
     ControlObjectClient self = NULL;
 
diff --git a/src/iec61850/client/client_goose_control.c b/src/iec61850/client/client_goose_control.c
index e61a2ec..67b1e9b 100644
--- a/src/iec61850/client/client_goose_control.c
+++ b/src/iec61850/client/client_goose_control.c
@@ -45,7 +45,7 @@ struct sClientGooseControlBlock {
 };
 
 ClientGooseControlBlock
-ClientGooseControlBlock_create(char* objectReference)
+ClientGooseControlBlock_create(const char* objectReference)
 {
     ClientGooseControlBlock self = (ClientGooseControlBlock) GLOBAL_CALLOC(1, sizeof(struct sClientGooseControlBlock));
 
@@ -100,7 +100,7 @@ ClientGooseControlBlock_getGoID(ClientGooseControlBlock self)
 }
 
 void
-ClientGooseControlBlock_setGoID(ClientGooseControlBlock self, char* goID)
+ClientGooseControlBlock_setGoID(ClientGooseControlBlock self, const char* goID)
 {
     if (self->goID == NULL)
         self->goID = MmsValue_newVisibleString(goID);
@@ -118,7 +118,7 @@ ClientGooseControlBlock_getDatSet(ClientGooseControlBlock self)
 }
 
 void
-ClientGooseControlBlock_setDatSet(ClientGooseControlBlock self, char* datSet)
+ClientGooseControlBlock_setDatSet(ClientGooseControlBlock self, const char* datSet)
 {
     if (self->datSet == NULL)
         self->datSet = MmsValue_newVisibleString(datSet);
@@ -285,7 +285,7 @@ private_ClientGooseControlBlock_updateValues(ClientGooseControlBlock self, MmsVa
 }
 
 ClientGooseControlBlock
-IedConnection_getGoCBValues(IedConnection self, IedClientError* error, char* goCBReference, ClientGooseControlBlock updateGoCB)
+IedConnection_getGoCBValues(IedConnection self, IedClientError* error, const char* goCBReference, ClientGooseControlBlock updateGoCB)
 {
     MmsError mmsError = MMS_ERROR_NONE;
     *error = IED_ERROR_OK;
@@ -297,7 +297,7 @@ IedConnection_getGoCBValues(IedConnection self, IedClientError* error, char* goC
 
     MmsMapping_getMmsDomainFromObjectReference(goCBReference, domainId);
 
-    char* itemIdStart = goCBReference + strlen(domainId) + 1;
+    const char* itemIdStart = goCBReference + strlen(domainId) + 1;
 
     char* separator = strchr(itemIdStart, '.');
 
diff --git a/src/iec61850/client/client_report.c b/src/iec61850/client/client_report.c
index 45a31ca..181e09d 100644
--- a/src/iec61850/client/client_report.c
+++ b/src/iec61850/client/client_report.c
@@ -222,7 +222,7 @@ ClientReport_getDataSetValues(ClientReport self)
 }
 
 static ClientReport
-lookupReportHandler(IedConnection self, char* rcbReference)
+lookupReportHandler(IedConnection self, const char* rcbReference)
 {
     LinkedList element = LinkedList_getNext(self->enabledReports);
 
@@ -239,7 +239,7 @@ lookupReportHandler(IedConnection self, char* rcbReference)
 }
 
 void
-IedConnection_installReportHandler(IedConnection self, char* rcbReference, char* rptId, ReportCallbackFunction handler,
+IedConnection_installReportHandler(IedConnection self, const char* rcbReference, const char* rptId, ReportCallbackFunction handler,
         void* handlerParameter)
 {
     ClientReport report = lookupReportHandler(self, rcbReference);
@@ -268,7 +268,7 @@ IedConnection_installReportHandler(IedConnection self, char* rcbReference, char*
 }
 
 void
-IedConnection_uninstallReportHandler(IedConnection self, char* rcbReference)
+IedConnection_uninstallReportHandler(IedConnection self, const char* rcbReference)
 {
     ClientReport report = lookupReportHandler(self, rcbReference);
 
@@ -279,7 +279,7 @@ IedConnection_uninstallReportHandler(IedConnection self, char* rcbReference)
 }
 
 void
-IedConnection_triggerGIReport(IedConnection self, IedClientError* error, char* rcbReference)
+IedConnection_triggerGIReport(IedConnection self, IedClientError* error, const char* rcbReference)
 {
     char domainId[65];
     char itemId[129];
diff --git a/src/iec61850/client/client_report_control.c b/src/iec61850/client/client_report_control.c
index 2e7407f..06537cf 100644
--- a/src/iec61850/client/client_report_control.c
+++ b/src/iec61850/client/client_report_control.c
@@ -32,7 +32,7 @@
 #include "mms_mapping.h"
 
 static bool
-isBufferedRcb(char* objectReference)
+isBufferedRcb(const char* objectReference)
 {
     char* separator = strchr(objectReference, '.');
 
@@ -46,7 +46,7 @@ isBufferedRcb(char* objectReference)
 }
 
 ClientReportControlBlock
-ClientReportControlBlock_create(char* objectReference)
+ClientReportControlBlock_create(const char* objectReference)
 {
     ClientReportControlBlock self = (ClientReportControlBlock) GLOBAL_CALLOC(1, sizeof(struct sClientReportControlBlock));
 
@@ -103,7 +103,7 @@ ClientReportControlBlock_getRptId(ClientReportControlBlock self)
 }
 
 void
-ClientReportControlBlock_setRptId(ClientReportControlBlock self, char* rptId)
+ClientReportControlBlock_setRptId(ClientReportControlBlock self, const char* rptId)
 {
     if (self->rptId == NULL)
         self->rptId = MmsValue_newVisibleString(rptId);
@@ -160,7 +160,7 @@ ClientReportControlBlock_getDataSetReference(ClientReportControlBlock self)
 }
 
 void
-ClientReportControlBlock_setDataSetReference(ClientReportControlBlock self, char* dataSetReference)
+ClientReportControlBlock_setDataSetReference(ClientReportControlBlock self, const char* dataSetReference)
 {
     if (self->datSet == NULL)
         self->datSet = MmsValue_newVisibleString(dataSetReference);
@@ -423,7 +423,7 @@ private_ClientReportControlBlock_updateValues(ClientReportControlBlock self, Mms
 
 
 ClientReportControlBlock
-IedConnection_getRCBValues(IedConnection self, IedClientError* error, char* rcbReference,
+IedConnection_getRCBValues(IedConnection self, IedClientError* error, const char* rcbReference,
         ClientReportControlBlock updateRcb)
 {
     MmsError mmsError = MMS_ERROR_NONE;
diff --git a/src/iec61850/client/ied_connection.c b/src/iec61850/client/ied_connection.c
index 8ef2843..26ab5e8 100644
--- a/src/iec61850/client/ied_connection.c
+++ b/src/iec61850/client/ied_connection.c
@@ -501,7 +501,7 @@ connectionLostHandler(MmsConnection connection, void* parameter)
 }
 
 void
-IedConnection_connect(IedConnection self, IedClientError* error, char* hostname, int tcpPort)
+IedConnection_connect(IedConnection self, IedClientError* error, const char* hostname, int tcpPort)
 {
     MmsError mmsError;
 
diff --git a/src/iec61850/common/iec61850_common.c b/src/iec61850/common/iec61850_common.c
index f21644f..df654c8 100644
--- a/src/iec61850/common/iec61850_common.c
+++ b/src/iec61850/common/iec61850_common.c
@@ -63,13 +63,13 @@ Quality_unsetFlag(Quality* self, int flag)
 
 
 Quality
-Quality_fromMmsValue(MmsValue* mmsValue)
+Quality_fromMmsValue(const MmsValue* mmsValue)
 {
     return (Quality) MmsValue_getBitStringAsInteger(mmsValue);
 }
 
 Dbpos
-Dbpos_fromMmsValue(MmsValue* mmsValue)
+Dbpos_fromMmsValue(const MmsValue* mmsValue)
 {
     return (Dbpos) MmsValue_getBitStringAsIntegerBigEndian(mmsValue);
 }
@@ -131,7 +131,7 @@ FunctionalConstraint_toString(FunctionalConstraint fc) {
 }
 
 FunctionalConstraint
-FunctionalConstraint_fromString(char* fcString)
+FunctionalConstraint_fromString(const char* fcString)
 {
     if (fcString[0] == 'S') {
         if (fcString[1] == 'T')
diff --git a/src/iec61850/inc/iec61850_client.h b/src/iec61850/inc/iec61850_client.h
index 748da87..b1b3401 100644
--- a/src/iec61850/inc/iec61850_client.h
+++ b/src/iec61850/inc/iec61850_client.h
@@ -186,7 +186,7 @@ IedConnection_setConnectTimeout(IedConnection self, uint32_t timeoutInMs);
  * \param tcpPort the TCP port number of the server to connect to
  */
 void
-IedConnection_connect(IedConnection self, IedClientError* error, char* hostname, int tcpPort);
+IedConnection_connect(IedConnection self, IedClientError* error, const char* hostname, int tcpPort);
 
 /**
  * \brief Abort the connection
@@ -325,7 +325,7 @@ IedConnection_getMmsConnection(IedConnection self);
  **************************************************/
 
 ClientGooseControlBlock
-ClientGooseControlBlock_create(char* dataAttributeReference);
+ClientGooseControlBlock_create(const char* dataAttributeReference);
 
 void
 ClientGooseControlBlock_destroy(ClientGooseControlBlock self);
@@ -340,13 +340,13 @@ char*
 ClientGooseControlBlock_getGoID(ClientGooseControlBlock self);
 
 void
-ClientGooseControlBlock_setGoID(ClientGooseControlBlock self, char* goID);
+ClientGooseControlBlock_setGoID(ClientGooseControlBlock self, const char* goID);
 
 char*
 ClientGooseControlBlock_getDatSet(ClientGooseControlBlock self);
 
 void
-ClientGooseControlBlock_setDatSet(ClientGooseControlBlock self, char* datSet);
+ClientGooseControlBlock_setDatSet(ClientGooseControlBlock self, const char* datSet);
 
 uint32_t
 ClientGooseControlBlock_getConfRev(ClientGooseControlBlock self);
@@ -420,7 +420,7 @@ ClientGooseControlBlock_setDstAddress_appid(ClientGooseControlBlock self, uint16
  *         the updateRcb parameter.
  */
 ClientGooseControlBlock
-IedConnection_getGoCBValues(IedConnection self, IedClientError* error, char* goCBReference, ClientGooseControlBlock updateGoCB);
+IedConnection_getGoCBValues(IedConnection self, IedClientError* error, const char* goCBReference, ClientGooseControlBlock updateGoCB);
 
 /**
  * \brief Write access to attributes of a GOOSE control block (GoCB) at the connected server
@@ -493,7 +493,7 @@ IedConnection_setGoCBValues(IedConnection self, IedClientError* error, ClientGoo
  *         the updateRcb parameter.
  */
 ClientReportControlBlock
-IedConnection_getRCBValues(IedConnection self, IedClientError* error, char* rcbReference,
+IedConnection_getRCBValues(IedConnection self, IedClientError* error, const char* rcbReference,
         ClientReportControlBlock updateRcb);
 
 /** Describes the reason for the inclusion of the element in the report */
@@ -624,7 +624,7 @@ typedef void (*ReportCallbackFunction) (void* parameter, ClientReport report);
  * \param handlerParameter user provided parameter that will be passed to the callback function
  */
 void
-IedConnection_installReportHandler(IedConnection self, char* rcbReference, char* rptId, ReportCallbackFunction handler,
+IedConnection_installReportHandler(IedConnection self, const char* rcbReference, const char* rptId, ReportCallbackFunction handler,
         void* handlerParameter);
 
 /**
@@ -634,7 +634,7 @@ IedConnection_installReportHandler(IedConnection self, char* rcbReference, char*
  * \param rcbReference object reference of the report control block
  */
 void
-IedConnection_uninstallReportHandler(IedConnection self, char* rcbReference);
+IedConnection_uninstallReportHandler(IedConnection self, const char* rcbReference);
 
 /**
  * \brief Trigger a general interrogation (GI) report for the specified report control block (RCB)
@@ -646,7 +646,7 @@ IedConnection_uninstallReportHandler(IedConnection self, char* rcbReference);
  * \param rcbReference object reference of the report control block
  */
 void
-IedConnection_triggerGIReport(IedConnection self, IedClientError* error, char* rcbReference);
+IedConnection_triggerGIReport(IedConnection self, IedClientError* error, const char* rcbReference);
 
 /****************************************
  * Access to received reports
@@ -788,7 +788,7 @@ ReasonForInclusion_getValueAsString(ReasonForInclusion reasonCode);
  **************************************************/
 
 ClientReportControlBlock
-ClientReportControlBlock_create(char* rcbReference);
+ClientReportControlBlock_create(const char* rcbReference);
 
 void
 ClientReportControlBlock_destroy(ClientReportControlBlock self);
@@ -803,7 +803,7 @@ char*
 ClientReportControlBlock_getRptId(ClientReportControlBlock self);
 
 void
-ClientReportControlBlock_setRptId(ClientReportControlBlock self, char* rptId);
+ClientReportControlBlock_setRptId(ClientReportControlBlock self, const char* rptId);
 
 bool
 ClientReportControlBlock_getRptEna(ClientReportControlBlock self);
@@ -837,7 +837,7 @@ ClientReportControlBlock_getDataSetReference(ClientReportControlBlock self);
  * \param dataSetReference the reference of the data set
  */
 void
-ClientReportControlBlock_setDataSetReference(ClientReportControlBlock self, char* dataSetReference);
+ClientReportControlBlock_setDataSetReference(ClientReportControlBlock self, const char* dataSetReference);
 
 uint32_t
 ClientReportControlBlock_getConfRev(ClientReportControlBlock self);
@@ -1256,7 +1256,7 @@ typedef enum {
  * \return the newly created instance or NULL if the creation failed
  */
 ControlObjectClient
-ControlObjectClient_create(char* objectReference, IedConnection connection);
+ControlObjectClient_create(const char* objectReference, IedConnection connection);
 
 void
 ControlObjectClient_destroy(ControlObjectClient self);
diff --git a/src/iec61850/inc/iec61850_common.h b/src/iec61850/inc/iec61850_common.h
index 795fce3..3341389 100644
--- a/src/iec61850/inc/iec61850_common.h
+++ b/src/iec61850/inc/iec61850_common.h
@@ -212,7 +212,7 @@ FunctionalConstraint_toString(FunctionalConstraint fc);
  * \brief parse a string treated as a functional constraint representation
  */
 FunctionalConstraint
-FunctionalConstraint_fromString(char* fcString);
+FunctionalConstraint_fromString(const char* fcString);
 
 /** @} */
 
@@ -262,7 +262,7 @@ bool
 Quality_isFlagSet(Quality* self, int flag);
 
 Quality
-Quality_fromMmsValue(MmsValue* mmsValue);
+Quality_fromMmsValue(const MmsValue* mmsValue);
 
 /** @} */
 
@@ -288,7 +288,7 @@ typedef enum {
  * \return the corresponding Dbpos value
  */
 Dbpos
-Dbpos_fromMmsValue(MmsValue* mmsValue);
+Dbpos_fromMmsValue(const MmsValue* mmsValue);
 
 /**
  * \brief conver Dbpos to MMS bit string
diff --git a/src/mms/inc/mms_value.h b/src/mms/inc/mms_value.h
index 42ac475..d700bbc 100644
--- a/src/mms/inc/mms_value.h
+++ b/src/mms/inc/mms_value.h
@@ -296,7 +296,7 @@ char*
 MmsValue_toString(MmsValue* self);
 
 void
-MmsValue_setVisibleString(MmsValue* self, char* string);
+MmsValue_setVisibleString(MmsValue* self, const char* string);
 
 
 /**
@@ -319,7 +319,7 @@ MmsValue_setBitStringBit(MmsValue* self, int bitPos, bool value);
  * \return the value of the bit (true = 1 / false = 0)
  */
 bool
-MmsValue_getBitStringBit(MmsValue* self, int bitPos);
+MmsValue_getBitStringBit(const MmsValue* self, int bitPos);
 
 /**
  * \brief Delete all bits (set to zero) of an MmsType object of type MMS_BITSTRING
@@ -336,7 +336,7 @@ MmsValue_deleteAllBitStringBits(MmsValue* self);
  * \param self MmsValue instance to operate on. Has to be of a type MMS_BITSTRING.
  */
 int
-MmsValue_getBitStringSize(MmsValue* self);
+MmsValue_getBitStringSize(const MmsValue* self);
 
 /**
  * \brief Get the number of bytes required by this bitString
@@ -344,7 +344,7 @@ MmsValue_getBitStringSize(MmsValue* self);
  * \param self MmsValue instance to operate on. Has to be of a type MMS_BITSTRING.
  */
 int
-MmsValue_getBitStringByteSize(MmsValue* self);
+MmsValue_getBitStringByteSize(const MmsValue* self);
 
 /**
  * \brief Count the number of set bits in a bit string.
@@ -352,7 +352,7 @@ MmsValue_getBitStringByteSize(MmsValue* self);
  * \param self MmsValue instance to operate on. Has to be of a type MMS_BITSTRING.
  */
 int
-MmsValue_getNumberOfSetBits(MmsValue* self);
+MmsValue_getNumberOfSetBits(const MmsValue* self);
 
 /**
  * Set all bits (set to one) of an MmsType object of type MMS_BITSTRING
@@ -371,7 +371,7 @@ MmsValue_setAllBitStringBits(MmsValue* self);
  * \param self MmsValue instance to operate on. Has to be of a type MMS_BITSTRING.
  */
 uint32_t
-MmsValue_getBitStringAsInteger(MmsValue* self);
+MmsValue_getBitStringAsInteger(const MmsValue* self);
 
 /**
  * \brief Convert an unsigned integer to a bit string
@@ -394,7 +394,7 @@ MmsValue_setBitStringFromInteger(MmsValue* self, uint32_t intValue);
  * \param self MmsValue instance to operate on. Has to be of a type MMS_BITSTRING.
  */
 uint32_t
-MmsValue_getBitStringAsIntegerBigEndian(MmsValue* self);
+MmsValue_getBitStringAsIntegerBigEndian(const MmsValue* self);
 
 /**
  * \brief Convert an unsigned integer to a bit string (big endian bit order)
@@ -559,7 +559,7 @@ MmsValue_getOctetStringBuffer(MmsValue* self);
  * \return indicates if the update has been successful (false if not)
  */
 bool
-MmsValue_update(MmsValue* self, MmsValue* source);
+MmsValue_update(MmsValue* self, const MmsValue* source);
 
 /**
  * \brief Check if two instances of MmsValue have the same value.
@@ -573,7 +573,7 @@ MmsValue_update(MmsValue* self, MmsValue* source);
  * \return true if both instances are of the same type and have the same value
  */
 bool
-MmsValue_equals(MmsValue* self, MmsValue* otherValue);
+MmsValue_equals(const MmsValue* self, const MmsValue* otherValue);
 
 /**
  * \brief Check if two (complex) instances of MmsValue have the same type.
@@ -588,7 +588,7 @@ MmsValue_equals(MmsValue* self, MmsValue* otherValue);
  * \return true if both instances and all their children are of the same type.
  */
 bool
-MmsValue_equalTypes(MmsValue* self, MmsValue* otherValue);
+MmsValue_equalTypes(const MmsValue* self, const MmsValue* otherValue);
 
 /*************************************************************************************
  * Constructors and destructors
@@ -745,7 +745,7 @@ MmsValue_deleteIfNotNull(MmsValue* value);
  * \return new MmsValue instance of type MMS_VISIBLE_STRING
  */
 MmsValue*
-MmsValue_newVisibleString(char* string);
+MmsValue_newVisibleString(const char* string);
 
 /**
  * \brief Create a new MmsValue instance of type MMS_VISIBLE_STRING.
diff --git a/src/mms/iso_mms/common/mms_value.c b/src/mms/iso_mms/common/mms_value.c
index 38400e6..1c9d16e 100644
--- a/src/mms/iso_mms/common/mms_value.c
+++ b/src/mms/iso_mms/common/mms_value.c
@@ -38,20 +38,20 @@
 #include <time.h> /* for ctime_r */
 
 static inline int
-bitStringByteSize(MmsValue* value)
+bitStringByteSize(const MmsValue* value)
 {
 	int bitSize = value->value.bitString.size;
 	return (bitSize / 8) + ((bitSize % 8) > 0);
 }
 
 int
-MmsValue_getBitStringByteSize(MmsValue* self)
+MmsValue_getBitStringByteSize(const MmsValue* self)
 {
    return bitStringByteSize(self);
 }
 
 static void
-updateStructuredComponent(MmsValue* self, MmsValue* update)
+updateStructuredComponent(MmsValue* self, const MmsValue* update)
 {
 	int componentCount;
 	MmsValue** selfValues;
@@ -96,7 +96,7 @@ MmsValue_newUnsignedFromBerInteger(Asn1PrimitiveValue* berInteger)
 }
 
 bool
-MmsValue_equals(MmsValue* self, MmsValue* otherValue)
+MmsValue_equals(const MmsValue* self, const MmsValue* otherValue)
 {
     if (self->type == otherValue->type) {
         switch (self->type) {
@@ -189,7 +189,7 @@ MmsValue_equals(MmsValue* self, MmsValue* otherValue)
 }
 
 bool
-MmsValue_equalTypes(MmsValue* self, MmsValue* otherValue)
+MmsValue_equalTypes(const MmsValue* self, const MmsValue* otherValue)
 {
     if (self->type == otherValue->type) {
         switch (self->type) {
@@ -220,7 +220,7 @@ MmsValue_equalTypes(MmsValue* self, MmsValue* otherValue)
 }
 
 bool
-MmsValue_update(MmsValue* self, MmsValue* update)
+MmsValue_update(MmsValue* self, const MmsValue* update)
 {
 	if (self->type == update->type) {
 		switch (self->type) {
@@ -314,7 +314,7 @@ MmsValue_newBitString(int bitSize)
 }
 
 static int
-getBitStringByteSize(MmsValue* self)
+getBitStringByteSize(const MmsValue* self)
 {
 	int byteSize;
 
@@ -361,13 +361,13 @@ MmsValue_setAllBitStringBits(MmsValue* self)
 }
 
 int
-MmsValue_getBitStringSize(MmsValue* self)
+MmsValue_getBitStringSize(const MmsValue* self)
 {
    return self->value.bitString.size;
 }
 
 int
-MmsValue_getNumberOfSetBits(MmsValue* self)
+MmsValue_getNumberOfSetBits(const MmsValue* self)
 {
     int setBitsCount = 0;
 
@@ -404,7 +404,7 @@ MmsValue_setBitStringBit(MmsValue* self, int bitPos, bool value)
 }
 
 bool
-MmsValue_getBitStringBit(MmsValue* self, int bitPos)
+MmsValue_getBitStringBit(const MmsValue* self, int bitPos)
 {
 	if (bitPos < self->value.bitString.size) {
 		int bytePos = bitPos / 8;
@@ -423,7 +423,7 @@ MmsValue_getBitStringBit(MmsValue* self, int bitPos)
 }
 
 uint32_t
-MmsValue_getBitStringAsInteger(MmsValue* self)
+MmsValue_getBitStringAsInteger(const MmsValue* self)
 {
     uint32_t value = 0;
 
@@ -454,7 +454,7 @@ MmsValue_setBitStringFromInteger(MmsValue* self, uint32_t intValue)
 }
 
 uint32_t
-MmsValue_getBitStringAsIntegerBigEndian(MmsValue* self)
+MmsValue_getBitStringAsIntegerBigEndian(const MmsValue* self)
 {
     uint32_t value = 0;
 
@@ -1435,7 +1435,7 @@ exit_function:
 }
 
 static inline void
-setVisibleStringValue(MmsValue* self, char* string)
+setVisibleStringValue(MmsValue* self, const char* string)
 {
 	if (self->value.visibleString.buf != NULL) {
 	    if (string != NULL) {
@@ -1464,7 +1464,7 @@ exit_function:
 }
 
 static MmsValue*
-MmsValue_newString(char* string, MmsType type)
+MmsValue_newString(const char* string, MmsType type)
 {
     MmsValue* self = (MmsValue*) GLOBAL_CALLOC(1, sizeof(MmsValue));
 
@@ -1497,7 +1497,7 @@ exit_function:
 }
 
 MmsValue*
-MmsValue_newVisibleString(char* string)
+MmsValue_newVisibleString(const char* string)
 {
 	return MmsValue_newString(string, MMS_VISIBLE_STRING);
 }
@@ -1687,7 +1687,7 @@ MmsValue_newMmsStringFromByteArray(uint8_t* byteArray, int size)
 }
 
 void
-MmsValue_setVisibleString(MmsValue* self, char* string)
+MmsValue_setVisibleString(MmsValue* self, const char* string)
 {
 	if (self->type == MMS_VISIBLE_STRING) {
 	    assert(self->value.visibleString.buf != NULL);