diff --git a/examples/iec61850_9_2_LE_example/iec61850_9_2_LE_example.c b/examples/iec61850_9_2_LE_example/iec61850_9_2_LE_example.c
index 52ee54a8..a7a016e6 100644
--- a/examples/iec61850_9_2_LE_example/iec61850_9_2_LE_example.c
+++ b/examples/iec61850_9_2_LE_example/iec61850_9_2_LE_example.c
@@ -226,7 +226,7 @@ main(int argc, char** argv)
                 SVPublisher_ASDU_setINT32(asdu, vol4, voltageN);
                 SVPublisher_ASDU_setQuality(asdu, vol4q, q);
 
-                SVPublisher_ASDU_setRefrTm(asdu, Hal_getTimeInMs());
+                SVPublisher_ASDU_setRefrTmNs(asdu, Hal_getTimeInNs());
 
                 SVPublisher_ASDU_setSmpCnt(asdu, (uint16_t) sampleCount);
 
diff --git a/hal/inc/hal_socket.h b/hal/inc/hal_socket.h
index 316058a7..5e6d15a9 100644
--- a/hal/inc/hal_socket.h
+++ b/hal/inc/hal_socket.h
@@ -57,6 +57,8 @@ extern "C" {
 /** Opaque reference for a server socket instance */
 typedef struct sServerSocket* ServerSocket;
 
+typedef struct sUdpSocket* UdpSocket;
+
 /** Opaque reference for a client or connection socket instance */
 typedef struct sSocket* Socket;
 
@@ -140,6 +142,18 @@ Handleset_destroy(HandleSet self);
 PAL_API ServerSocket
 TcpServerSocket_create(const char* address, int port);
 
+PAL_API UdpSocket
+UdpSocket_create();
+
+PAL_API bool
+UdpSocket_bind(UdpSocket self, const char* address, int port);
+
+PAL_API bool
+UdpSocket_sendTo(UdpSocket self, const char* address, int port, uint8_t* msg, int msgSize);
+
+PAL_API int
+UdpSocket_receiveFrom(UdpSocket self, char** address, int maxAddrSize, uint8_t* msg, int msgSize);
+
 
 PAL_API void
 ServerSocket_listen(ServerSocket self);
diff --git a/hal/inc/hal_time.h b/hal/inc/hal_time.h
index 0e57d338..8944aa19 100644
--- a/hal/inc/hal_time.h
+++ b/hal/inc/hal_time.h
@@ -1,7 +1,7 @@
 /*
  *  time.c
  *
- *  Copyright 2013, 2014 Michael Zillgith
+ *  Copyright 2013-2020 Michael Zillgith
  *
  *  This file is part of libIEC61850.
  *
@@ -46,6 +46,9 @@ extern "C" {
  * @{
  */
 
+typedef uint64_t nsSinceEpoch;
+typedef uint64_t msSinceEpoch;
+
 /**
  * Get the system time in milliseconds.
  *
@@ -54,9 +57,23 @@ extern "C" {
  *
  * \return the system time with millisecond resolution.
  */
-PAL_API uint64_t
+PAL_API msSinceEpoch
 Hal_getTimeInMs(void);
 
+/**
+ * Get the system time in nanoseconds.
+ *
+ * The time value returned as 64-bit unsigned integer should represent the nanoseconds
+ * since the UNIX epoch (1970/01/01 00:00 UTC).
+ *
+ * \return the system time with nanosecond resolution.
+ */
+PAL_API nsSinceEpoch
+Hal_getTimeInNs();
+
+PAL_API bool
+Hal_setTimeInNs(nsSinceEpoch nsTime);
+
 /*! @} */
 
 /*! @} */
diff --git a/hal/socket/linux/socket_linux.c b/hal/socket/linux/socket_linux.c
index 7d04e4ff..020c850d 100644
--- a/hal/socket/linux/socket_linux.c
+++ b/hal/socket/linux/socket_linux.c
@@ -58,6 +58,10 @@ struct sServerSocket {
     int backLog;
 };
 
+struct sUdpSocket {
+    int fd;
+};
+
 struct sHandleSet {
     LinkedList sockets;
     bool pollfdIsUpdated;
@@ -184,26 +188,26 @@ Socket_activateTcpKeepAlive(Socket self, int idleTime, int interval, int count)
 
     if (setsockopt(self->fd, SOL_SOCKET, SO_KEEPALIVE, &optval, optlen)) {
         if (DEBUG_SOCKET)
-            printf("Failed to enable TCP keepalive\n");
+            printf("SOCKET: Failed to enable TCP keepalive\n");
     }
 
 #if defined TCP_KEEPCNT
     optval = idleTime;
     if (setsockopt(self->fd, IPPROTO_TCP, TCP_KEEPIDLE, &optval, optlen)) {
         if (DEBUG_SOCKET)
-            printf("Failed to set TCP keepalive TCP_KEEPIDLE parameter\n");
+            printf("SOCKET: Failed to set TCP keepalive TCP_KEEPIDLE parameter\n");
     }
 
     optval = interval;
     if (setsockopt(self->fd, IPPROTO_TCP, TCP_KEEPINTVL, &optval, optlen)) {
         if (DEBUG_SOCKET)
-            printf("Failed to set TCP keepalive TCP_KEEPINTVL parameter\n");
+            printf("SOCKET: Failed to set TCP keepalive TCP_KEEPINTVL parameter\n");
     }
 
     optval = count;
     if (setsockopt(self->fd, IPPROTO_TCP, TCP_KEEPCNT, &optval, optlen)) {
         if (DEBUG_SOCKET)
-            printf("Failed to set TCP keepalive TCP_KEEPCNT parameter\n");
+            printf("SOCKET: Failed to set TCP keepalive TCP_KEEPCNT parameter\n");
     }
 #endif /* TCP_KEEPCNT */
 
@@ -343,7 +347,7 @@ closeAndShutdownSocket(int socketFd)
     if (socketFd != -1) {
 
         if (DEBUG_SOCKET)
-            printf("socket_linux.c: call shutdown for %i!\n", socketFd);
+            printf("SOCKET: call shutdown for %i!\n", socketFd);
 
         /* shutdown is required to unblock read or accept in another thread! */
         shutdown(socketFd, SHUT_RDWR);
@@ -505,7 +509,6 @@ Socket_connect(Socket self, const char* address, int port)
     return false;
 }
 
-
 static char*
 convertAddressToStr(struct sockaddr_storage* addr)
 {
@@ -667,3 +670,94 @@ Socket_destroy(Socket self)
 
     GLOBAL_FREEMEM(self);
 }
+
+UdpSocket
+UdpSocket_create()
+{
+    UdpSocket self = NULL;
+
+    int sock = socket(AF_INET, SOCK_DGRAM, 0);
+
+    if (sock != -1) {
+        self = (UdpSocket) GLOBAL_MALLOC(sizeof(struct sSocket));
+
+        self->fd = sock;
+    }
+    else {
+        if (DEBUG_SOCKET)
+            printf("SOCKET: failed to create UDP socket (errno=%i)\n", errno);
+    }
+
+    return self;
+}
+
+bool
+UdpSocket_bind(UdpSocket self, const char* address, int port)
+{
+    struct sockaddr_in localAddress;
+
+    if (!prepareServerAddress(address, port, &localAddress)) {
+        close(self->fd);
+        self->fd = 0;
+        return false;
+    }
+
+    int result = bind(self->fd, (struct sockaddr*)&localAddress, sizeof(localAddress));
+
+    if (result == -1) {
+        if (DEBUG_SOCKET)
+            printf("SOCKET: failed to bind UDP socket (errno=%i)\n", errno);
+
+        close(self->fd);
+        self->fd = 0;
+
+        return false;
+    }
+
+    return true;
+}
+
+bool
+UdpSocket_sendTo(UdpSocket self, const char* address, int port, uint8_t* msg, int msgSize)
+{
+    struct sockaddr_in remoteAddress;
+
+    if (!prepareServerAddress(address, port, &remoteAddress)) {
+
+        if (DEBUG_SOCKET)
+            printf("SOCKET: failed to lookup remote address %s\n", address);
+
+        return false;
+    }
+
+    int result = sendto(self->fd, msg, msgSize, 0, (struct sockaddr*)&remoteAddress, sizeof(remoteAddress));
+
+    if (result == msgSize) {
+        return true;
+    }
+    else if (result == -1) {
+        if (DEBUG_SOCKET)
+            printf("SOCKET: failed to send UDP message (errno=%i)\n", errno);
+    }
+    else {
+        if (DEBUG_SOCKET)
+            printf("SOCKET: failed to send UDP message (insufficient data sent)\n");
+    }
+
+    return false;
+}
+
+int
+UdpSocket_receiveFrom(UdpSocket self, char** address, int maxAddrSize, uint8_t* msg, int msgSize)
+{
+    struct sockaddr_in remoteAddress;
+
+    int result = recvfrom(self->fd, msg, msgSize, MSG_DONTWAIT, NULL, NULL);
+
+    if (result == -1) {
+        if (DEBUG_SOCKET)
+            printf("SOCKET: failed to receive UDP message (errno=%i)\n", errno);
+    }
+
+    return result;
+}
diff --git a/hal/socket/win32/socket_win32.c b/hal/socket/win32/socket_win32.c
index 2368f32a..d42a3674 100644
--- a/hal/socket/win32/socket_win32.c
+++ b/hal/socket/win32/socket_win32.c
@@ -58,6 +58,10 @@ struct sHandleSet {
    SOCKET maxHandle;
 };
 
+struct sUdpSocket {
+	SOCKET fd;
+};
+
 HandleSet
 Handleset_new(void)
 {
@@ -612,3 +616,101 @@ Socket_destroy(Socket self)
 
     GLOBAL_FREEMEM(self);
 }
+
+UdpSocket
+UdpSocket_create()
+{
+    UdpSocket self = NULL;
+
+    int sock = socket(AF_INET, SOCK_DGRAM, 0);
+
+    if (sock != -1) {
+        self = (UdpSocket) GLOBAL_MALLOC(sizeof(struct sSocket));
+
+        self->fd = sock;
+
+        setSocketNonBlocking((Socket)self);
+    }
+    else {
+        if (DEBUG_SOCKET)
+            printf("SOCKET: failed to create UDP socket (errno=%i)\n", errno);
+    }
+
+    return self;
+}
+
+bool
+UdpSocket_bind(UdpSocket self, const char* address, int port)
+{
+    struct sockaddr_in localAddress;
+
+    if (!prepareServerAddress(address, port, &localAddress)) {
+		closesocket(self->fd);
+        self->fd = 0;
+        return false;
+    }
+
+    int result = bind(self->fd, (struct sockaddr*)&localAddress, sizeof(localAddress));
+
+    if (result == -1) {
+        if (DEBUG_SOCKET)
+            printf("SOCKET: failed to bind UDP socket (errno=%i)\n", errno);
+
+		closesocket(self->fd);
+        self->fd = 0;
+
+        return false;
+    }
+
+    return true;
+}
+
+bool
+UdpSocket_sendTo(UdpSocket self, const char* address, int port, uint8_t* msg, int msgSize)
+{
+    struct sockaddr_in remoteAddress;
+
+    if (!prepareServerAddress(address, port, &remoteAddress)) {
+
+        if (DEBUG_SOCKET)
+            printf("SOCKET: failed to lookup remote address %s\n", address);
+
+        return false;
+    }
+
+    int result = sendto(self->fd, (const char*) msg, msgSize, 0, (struct sockaddr*)&remoteAddress, sizeof(remoteAddress));
+
+    if (result == msgSize) {
+        return true;
+    }
+    else if (result == -1) {
+        if (DEBUG_SOCKET)
+            printf("SOCKET: failed to send UDP message (errno=%i)\n", errno);
+    }
+    else {
+        if (DEBUG_SOCKET)
+            printf("SOCKET: failed to send UDP message (insufficient data sent)\n");
+    }
+
+    return false;
+}
+
+int
+UdpSocket_receiveFrom(UdpSocket self, char** address, int maxAddrSize, uint8_t* msg, int msgSize)
+{
+    struct sockaddr_in remoteAddress;
+
+    int result = recvfrom(self->fd, (char*) msg, msgSize, 0, NULL, NULL);
+
+    if (result == 0) /* peer has closed socket */
+        return -1;
+
+    if (result == SOCKET_ERROR) {
+        if (WSAGetLastError() == WSAEWOULDBLOCK)
+            return 0;
+        else
+            return -1;
+    }
+
+    return result;
+}
diff --git a/hal/time/unix/time.c b/hal/time/unix/time.c
index f7951fde..6565da33 100644
--- a/hal/time/unix/time.c
+++ b/hal/time/unix/time.c
@@ -39,7 +39,7 @@ Hal_getTimeInMs()
 
 #include <sys/time.h>
 
-uint64_t
+msSinceEpoch
 Hal_getTimeInMs()
 {
     struct timeval now;
@@ -49,5 +49,34 @@ Hal_getTimeInMs()
     return ((uint64_t) now.tv_sec * 1000LL) + (now.tv_usec / 1000);
 }
 
+nsSinceEpoch
+Hal_getTimeInNs()
+{
+    struct timespec now;
+
+    clock_gettime(CLOCK_REALTIME, &now);
+
+    nsSinceEpoch nsTime = now.tv_sec * 1000000000UL;
+    nsTime += now.tv_nsec;
+
+    return nsTime;
+}
+
+bool
+Hal_setTimeInNs(nsSinceEpoch nsTime)
+{
+    struct timespec tv;
+
+    tv.tv_sec = nsTime / 1000000000UL;
+    tv.tv_nsec = nsTime % 1000000000UL;
+
+    if (clock_settime(CLOCK_REALTIME, &tv) < 0) {
+        return false;
+    }
+
+    return true;
+}
+
+
 #endif
 
diff --git a/src/iec61850/common/iec61850_common.c b/src/iec61850/common/iec61850_common.c
index 704be1da..58cb146f 100644
--- a/src/iec61850/common/iec61850_common.c
+++ b/src/iec61850/common/iec61850_common.c
@@ -1,7 +1,7 @@
 /*
  * iec61850_common.c
  *
- *  Copyright 2013 Michael Zillgith
+ *  Copyright 2013-2020 Michael Zillgith
  *
  *  This file is part of libIEC61850.
  *
@@ -341,14 +341,12 @@ Timestamp_setSubsecondPrecision(Timestamp* self, int subsecondPrecision)
 void
 Timestamp_setTimeInSeconds(Timestamp* self, uint32_t secondsSinceEpoch)
 {
-    uint8_t* timeArray = (uint8_t*) &secondsSinceEpoch;
     uint8_t* valueArray =  self->val;
 
-#if (ORDER_LITTLE_ENDIAN == 1)
-        memcpyReverseByteOrder(valueArray, timeArray, 4);
-#else
-        memcpy(valueArray, timeArray, 4);
-#endif
+    valueArray[0] = (secondsSinceEpoch / 0x1000000 & 0xff);
+    valueArray[1] = (secondsSinceEpoch / 0x10000 & 0xff);
+    valueArray[2] = (secondsSinceEpoch / 0x100 & 0xff);
+    valueArray[3] = (secondsSinceEpoch & 0xff);
 
     self->val[4] = 0;
     self->val[5] = 0;
@@ -358,18 +356,16 @@ Timestamp_setTimeInSeconds(Timestamp* self, uint32_t secondsSinceEpoch)
 }
 
 void
-Timestamp_setTimeInMilliseconds(Timestamp* self, uint64_t millisSinceEpoch)
+Timestamp_setTimeInMilliseconds(Timestamp* self, msSinceEpoch millisSinceEpoch)
 {
     uint32_t timeval32 = (uint32_t) (millisSinceEpoch / 1000LL);
 
-    uint8_t* timeArray = (uint8_t*) &timeval32;
     uint8_t* valueArray = self->val;
 
-#if (ORDER_LITTLE_ENDIAN == 1)
-        memcpyReverseByteOrder(valueArray, timeArray, 4);
-#else
-        memcpy(valueArray, timeArray, 4);
-#endif
+    valueArray[0] = (timeval32 / 0x1000000 & 0xff);
+    valueArray[1] = (timeval32 / 0x10000 & 0xff);
+    valueArray[2] = (timeval32 / 0x100 & 0xff);
+    valueArray[3] = (timeval32 & 0xff);
 
     uint32_t remainder = (millisSinceEpoch % 1000LL);
     uint32_t fractionOfSecond = (remainder) * 16777 + ((remainder * 216) / 1000);
@@ -382,32 +378,57 @@ Timestamp_setTimeInMilliseconds(Timestamp* self, uint64_t millisSinceEpoch)
     /* don't touch time quality */
 }
 
+void
+Timestamp_setTimeInNanoseconds(Timestamp* self, nsSinceEpoch nsTime)
+{
+    uint32_t timeval32 = (nsTime / 1000000000LLU);
+
+    uint8_t* valueArray = self->val;
+
+    valueArray[0] = (timeval32 / 0x1000000 & 0xff);
+    valueArray[1] = (timeval32 / 0x10000 & 0xff);
+    valueArray[2] = (timeval32 / 0x100 & 0xff);
+    valueArray[3] = (timeval32 & 0xff);
+
+    uint64_t remainder = (nsTime % 1000000000LLU);
+
+    remainder = remainder << 24;
+    remainder = remainder / 1000000000UL;
+
+    uint32_t fractionOfSecond = (uint32_t) remainder;
+
+    /* encode fraction of second */
+    valueArray[4] = ((fractionOfSecond >> 16) & 0xff);
+    valueArray[5] = ((fractionOfSecond >> 8) & 0xff);
+    valueArray[6] = (fractionOfSecond & 0xff);
+
+    /* don't touch time quality */
+}
+
 uint32_t
 Timestamp_getTimeInSeconds(Timestamp* self)
 {
     uint32_t timeval32;
     uint8_t* valueArray = self->val;
 
-#if (ORDER_LITTLE_ENDIAN == 1)
-    memcpyReverseByteOrder((uint8_t*) &timeval32, valueArray, 4);
-#else
-    memcpy((uint8_t*) &timeval32, valueArray, 4);
-#endif
+    timeval32 = valueArray[3];
+    timeval32 += valueArray[2] * 0x100;
+    timeval32 += valueArray[1] * 0x10000;
+    timeval32 += valueArray[0] * 0x1000000;
 
     return timeval32;
 }
 
-uint64_t
+msSinceEpoch
 Timestamp_getTimeInMs(Timestamp* self)
 {
     uint32_t timeval32;
     uint8_t* valueArray = self->val;
 
-#if (ORDER_LITTLE_ENDIAN == 1)
-    memcpyReverseByteOrder((uint8_t*) &timeval32, valueArray, 4);
-#else
-    memcpy((uint8_t*) &timeval32, valueArray, 4);
-#endif
+    timeval32 = valueArray[3];
+    timeval32 += valueArray[2] * 0x100;
+    timeval32 += valueArray[1] * 0x10000;
+    timeval32 += valueArray[0] * 0x1000000;
 
     uint32_t fractionOfSecond = 0;
 
@@ -422,6 +443,33 @@ Timestamp_getTimeInMs(Timestamp* self)
     return (uint64_t) msVal;
 }
 
+nsSinceEpoch
+Timestamp_getTimeInNs(Timestamp* self)
+{
+    uint32_t timeval32;
+    uint8_t* valueArray = self->val;
+
+    timeval32 = valueArray[3];
+    timeval32 += valueArray[2] * 0x100;
+    timeval32 += valueArray[1] * 0x10000;
+    timeval32 += valueArray[0] * 0x1000000;
+
+    uint32_t fractionOfSecond;
+
+    fractionOfSecond = valueArray[6];
+    fractionOfSecond += valueArray[5] * 0x100;
+    fractionOfSecond += valueArray[4] * 0x10000;
+
+    uint64_t nsVal = fractionOfSecond;
+
+    nsVal = nsVal * 1000000000UL;
+    nsVal = nsVal >> 24;
+
+    uint64_t timeval64 = (uint64_t) timeval32 * 1000000000LLU + nsVal;
+
+    return timeval64;
+}
+
 void
 Timestamp_setByMmsUtcTime(Timestamp* self, MmsValue* mmsValue)
 {
diff --git a/src/iec61850/inc/iec61850_common.h b/src/iec61850/inc/iec61850_common.h
index dfe1c553..d934aff2 100644
--- a/src/iec61850/inc/iec61850_common.h
+++ b/src/iec61850/inc/iec61850_common.h
@@ -418,9 +418,12 @@ Timestamp_clearFlags(Timestamp* self);
 LIB61850_API uint32_t
 Timestamp_getTimeInSeconds(Timestamp* self);
 
-LIB61850_API uint64_t
+LIB61850_API msSinceEpoch
 Timestamp_getTimeInMs(Timestamp* self);
 
+LIB61850_API nsSinceEpoch
+Timestamp_getTimeInNs(Timestamp* self);
+
 LIB61850_API bool
 Timestamp_isLeapSecondKnown(Timestamp* self);
 
@@ -450,11 +453,39 @@ Timestamp_getSubsecondPrecision(Timestamp* self);
 LIB61850_API void
 Timestamp_setSubsecondPrecision(Timestamp* self, int subsecondPrecision);
 
+/**
+ * \brief Set the time in seconds
+ *
+ * NOTE: the fractionOfSecond part is set to zero
+ * NOTE: the subSecondPrecision is not touched
+ *
+ * \param self the Timestamp instance
+ * \param secondsSinceEpoch the seconds since unix epoch (unix timestamp)
+ */
 LIB61850_API void
 Timestamp_setTimeInSeconds(Timestamp* self, uint32_t secondsSinceEpoch);
 
+/**
+ * \brief Set the time in milliseconds
+ *
+ * NOTE: the subSecondPrecision is not touched
+ *
+ * \param self the Timestamp instance
+ * \param msTime the milliseconds since unix epoch
+ */
+LIB61850_API void
+Timestamp_setTimeInMilliseconds(Timestamp* self, msSinceEpoch msTime);
+
+/**
+ * \brief Set the time in nanoseconds
+ *
+ * NOTE: the subSecondPrecision is not touched
+ *
+ * \param self the Timestamp instance
+ * \param msTime the nanoseconds since unix epoch
+ */
 LIB61850_API void
-Timestamp_setTimeInMilliseconds(Timestamp* self, uint64_t millisSinceEpoch);
+Timestamp_setTimeInNanoseconds(Timestamp* self, nsSinceEpoch nsTime);
 
 LIB61850_API void
 Timestamp_setByMmsUtcTime(Timestamp* self, MmsValue* mmsValue);
diff --git a/src/sampled_values/sv_publisher.c b/src/sampled_values/sv_publisher.c
index 1f7b0110..61346917 100644
--- a/src/sampled_values/sv_publisher.c
+++ b/src/sampled_values/sv_publisher.c
@@ -58,12 +58,11 @@ struct sSVPublisher_ASDU {
     uint16_t smpCntLimit;
     uint32_t confRev;
 
-    uint64_t refrTm;
+    Timestamp* refrTm;
     uint8_t smpMod;
     uint16_t smpRate;
 
     uint8_t* smpCntBuf;
-    uint8_t* refrTmBuf;
     uint8_t* smpSynchBuf;
 
     SVPublisher_ASDU _next;
@@ -265,40 +264,6 @@ encodeInt64FixedSize(int64_t value, uint8_t* buffer, int bufPos)
     return bufPos;
 }
 
-static int
-encodeUtcTime(uint64_t timeval, uint8_t* buffer, int bufPos)
-{
-    uint32_t timeval32 = (timeval / 1000LL);
-
-    uint8_t* timeArray = (uint8_t*) &timeval32;
-    uint8_t* valueArray = buffer + bufPos;
-
-#if (ORDER_LITTLE_ENDIAN == 1)
-    valueArray[0] = timeArray[3];
-    valueArray[1] = timeArray[2];
-    valueArray[2] = timeArray[1];
-    valueArray[3] = timeArray[0];
-#else
-    valueArray[0] = timeArray[0];
-    valueArray[1] = timeArray[1];
-    valueArray[2] = timeArray[2];
-    valueArray[3] = timeArray[3];
-#endif
-
-    uint32_t remainder = (timeval % 1000LL);
-    uint32_t fractionOfSecond = (remainder) * 16777 + ((remainder * 216) / 1000);
-
-    /* encode fraction of second */
-    valueArray[4] = ((fractionOfSecond >> 16) & 0xff);
-    valueArray[5] = ((fractionOfSecond >> 8) & 0xff);
-    valueArray[6] = (fractionOfSecond & 0xff);
-
-    /* encode time quality */
-    valueArray[7] = 0x0a; /* 10 bit sub-second time accuracy */
-
-    return bufPos + 8;
-}
-
 SVPublisher
 SVPublisher_createEx(CommParameters* parameters, const char* interfaceId, bool useVlanTag)
 {
@@ -332,7 +297,6 @@ SVPublisher_addASDU(SVPublisher self, const char* svID, const char* datset, uint
     newAsdu->datset = datset;
     newAsdu->confRev = confRev;
     newAsdu->smpCntLimit = UINT16_MAX;
-
     newAsdu->_next = NULL;
 
     /* append new ASDU to list */
@@ -417,8 +381,8 @@ SVPublisher_ASDU_encodeToBuffer(SVPublisher_ASDU self, uint8_t* buffer, int bufP
     /* RefrTm */
     if (self->hasRefrTm) {
         bufPos = BerEncoder_encodeTL(0x84, 8, buffer, bufPos);
-        self->refrTmBuf = buffer + bufPos;
-        bufPos = encodeUtcTime(self->refrTm, buffer, bufPos);
+        self->refrTm = (Timestamp*) (buffer + bufPos);
+        bufPos += 8;
     }
 
     /* SmpSynch */
@@ -724,13 +688,34 @@ SVPublisher_ASDU_enableRefrTm(SVPublisher_ASDU self)
 }
 
 void
-SVPublisher_ASDU_setRefrTm(SVPublisher_ASDU self, uint64_t refrTm)
+SVPublisher_ASDU_setRefrTmNs(SVPublisher_ASDU self, nsSinceEpoch refrTmNs)
+{
+    self->hasRefrTm = true;
+
+    if (self->refrTm) {
+        Timestamp_setTimeInNanoseconds(self->refrTm, refrTmNs);
+        Timestamp_setSubsecondPrecision(self->refrTm, 20);
+    }
+}
+
+void
+SVPublisher_ASDU_setRefrTm(SVPublisher_ASDU self, msSinceEpoch refrTm)
+{
+    self->hasRefrTm = true;
+
+    if (self->refrTm) {
+        Timestamp_setTimeInMilliseconds(self->refrTm, refrTm);
+        Timestamp_setSubsecondPrecision(self->refrTm, 10);
+    }
+}
+
+void
+SVPublisher_ASDU_setRefrTmByTimestamp(SVPublisher_ASDU self, Timestamp* refrTm)
 {
     self->hasRefrTm = true;
-    self->refrTm = refrTm;
 
-    if (self->refrTmBuf != NULL)
-        encodeUtcTime(self->refrTm, self->refrTmBuf, 0);
+    if (self->refrTm)
+        memcpy(self->refrTm, refrTm, 8);
 }
 
 void
diff --git a/src/sampled_values/sv_publisher.h b/src/sampled_values/sv_publisher.h
index 3c59c1b4..c737ae5f 100644
--- a/src/sampled_values/sv_publisher.h
+++ b/src/sampled_values/sv_publisher.h
@@ -329,12 +329,34 @@ LIB61850_API void
 SVPublisher_ASDU_enableRefrTm(SVPublisher_ASDU self);
 
 /**
- * \brief Set the refresh time attribute of the ASDU.
+ * \brief Set the refresh time attribute of the ASDU with nanosecond resolution
  *
  * \param[in] self the Sampled Values ASDU instance.
+ * \param[in] refrTmNs the refresh time value with nanoseconds resolution.
  */
 LIB61850_API void
-SVPublisher_ASDU_setRefrTm(SVPublisher_ASDU self, uint64_t refrTm);
+SVPublisher_ASDU_setRefrTmNs(SVPublisher_ASDU self, nsSinceEpoch refrTmNs);
+
+/**
+ * \brief Set the refresh time attribute of the ASDU with millisecond resolution
+ *
+ * \param[in] self the Sampled Values ASDU instance.
+ * \param[in] refrTmNs the refresh time value with with milliseconds resolution.
+ */
+LIB61850_API void
+SVPublisher_ASDU_setRefrTm(SVPublisher_ASDU self, msSinceEpoch refrTm);
+
+/**
+ * \brief Set the refresh time attribute of the ASDU
+ *
+ * NOTE: Using this function you can control the time quality flags and the
+ * sub second precision (number of valid bits) of the RefrTm value.
+ *
+ * \param[in] self the Sampled Values ASDU instance.
+ * \param[in] refrTm the refresh time value
+ */
+LIB61850_API void
+SVPublisher_ASDU_setRefrTmByTimestamp(SVPublisher_ASDU self, Timestamp* refrTm);
 
 /**
  * \brief Set the sample mode attribute of the ASDU.
diff --git a/src/sampled_values/sv_subscriber.c b/src/sampled_values/sv_subscriber.c
index 1d49b39c..fe014659 100644
--- a/src/sampled_values/sv_subscriber.c
+++ b/src/sampled_values/sv_subscriber.c
@@ -339,7 +339,7 @@ parseASDU(SVReceiver self, SVSubscriber subscriber, uint8_t* buffer, int length)
         if (SVSubscriber_ASDU_hasDatSet(&asdu))
             printf("SV_SUBSCRIBER:     DatSet: %s\n", asdu.datSet);
         if (SVSubscriber_ASDU_hasRefrTm(&asdu))
-            printf("SV_SUBSCRIBER:     RefrTm: %lu\n", SVSubscriber_ASDU_getRefrTmAsMs(&asdu));
+            printf("SV_SUBSCRIBER:     RefrTm[ns]: %lu\n", SVSubscriber_ASDU_getRefrTmAsNs(&asdu));
         if (SVSubscriber_ASDU_hasSmpMod(&asdu))
             printf("SV_SUBSCRIBER:     SmpMod: %d\n", SVSubscriber_ASDU_getSmpMod(&asdu));
         if (SVSubscriber_ASDU_hasSmpRate(&asdu))
@@ -599,8 +599,8 @@ SVSubscriber_ASDU_getSmpCnt(SVSubscriber_ASDU self)
     return retVal;
 }
 
-static uint64_t
-decodeUtcTime(uint8_t* buffer, uint8_t* timeQuality)
+static nsSinceEpoch
+decodeUtcTimeToNsTime(uint8_t* buffer, uint8_t* timeQuality)
 {
     uint32_t timeval32;
 
@@ -609,33 +609,45 @@ decodeUtcTime(uint8_t* buffer, uint8_t* timeQuality)
     timeval32 += buffer[1] * 0x10000;
     timeval32 += buffer[0] * 0x1000000;
 
-    uint32_t msVal;
-
     uint32_t fractionOfSecond;
 
     fractionOfSecond = buffer[6];
     fractionOfSecond += buffer[5] * 0x100;
     fractionOfSecond += buffer[4] * 0x10000;
 
-    msVal = (uint32_t) (((uint64_t) fractionOfSecond * 1000) / 16777215);
+    uint64_t nsVal = fractionOfSecond;
+
+    nsVal = nsVal * 1000000000UL;
+    nsVal = nsVal >> 24;
 
     if (timeQuality != NULL)
         *timeQuality = buffer[7];
 
-    uint64_t timeval64 = (uint64_t) timeval32 * 1000 + (uint64_t) msVal;
+    uint64_t timeval64 = (uint64_t) timeval32 * 1000000000LLU + nsVal;
 
     return timeval64;
 }
 
-uint64_t
+msSinceEpoch
 SVSubscriber_ASDU_getRefrTmAsMs(SVSubscriber_ASDU self)
 {
-    uint64_t msTime = 0;
+    msSinceEpoch msTime = 0;
+
+    if (self->refrTm != NULL)
+        msTime = decodeUtcTimeToNsTime(self->refrTm, NULL);
+
+    return (msTime / 1000000LLU);
+}
+
+nsSinceEpoch
+SVSubscriber_ASDU_getRefrTmAsNs(SVSubscriber_ASDU self)
+{
+    nsSinceEpoch nsTime = 0;
 
     if (self->refrTm != NULL)
-        msTime = decodeUtcTime(self->refrTm, NULL);
+        nsTime = decodeUtcTimeToNsTime(self->refrTm, NULL);
 
-    return msTime;
+    return nsTime;
 }
 
 bool
diff --git a/src/sampled_values/sv_subscriber.h b/src/sampled_values/sv_subscriber.h
index 44ee9066..dd072679 100644
--- a/src/sampled_values/sv_subscriber.h
+++ b/src/sampled_values/sv_subscriber.h
@@ -376,7 +376,7 @@ LIB61850_API bool
 SVSubscriber_ASDU_hasSmpRate(SVSubscriber_ASDU self);
 
 /**
- * \brief Get the RefrTim value included in SV ASDU as ms timestamp
+ * \brief Get the RefrTim value included in SV ASDU as milliseconds timestamp
  *
  * \param self ASDU object instance
  *
@@ -385,6 +385,16 @@ SVSubscriber_ASDU_hasSmpRate(SVSubscriber_ASDU self);
 LIB61850_API uint64_t
 SVSubscriber_ASDU_getRefrTmAsMs(SVSubscriber_ASDU self);
 
+/**
+ * \brief Get the RefrTim value included in SV ASDU as nanoseconds timestamp
+ *
+ * \param self ASDU object instance
+ *
+ * \return the time value as nanoseconds timestamp or 0 if RefrTm is not present in the SV ASDU
+ */
+LIB61850_API nsSinceEpoch
+SVSubscriber_ASDU_getRefrTmAsNs(SVSubscriber_ASDU self);
+
 /**
  * \brief Get an INT8 data value in the data part of the ASDU
  *