diff --git a/examples/platforms/cc2538/radio.c b/examples/platforms/cc2538/radio.c
index 48bd9a2aa..87326940b 100644
--- a/examples/platforms/cc2538/radio.c
+++ b/examples/platforms/cc2538/radio.c
@@ -111,6 +111,17 @@ void setChannel(uint8_t channel)
     HWREG(RFCORE_XREG_FREQCTRL) = 11 + (channel - 11) * 5;
 }
 
+void otPlatRadioGetIeeeEui64(otInstance *aInstance, uint8_t *aIeeeEui64)
+{
+    uint8_t *eui64 = (uint8_t *)IEEE_EUI64;
+    (void)aInstance;
+
+    for (uint8_t i = 0; i < OT_EXT_ADDRESS_SIZE; i++)
+    {
+        aIeeeEui64[i] = eui64[7 - i];
+    }
+}
+
 ThreadError otPlatRadioSetPanId(otInstance *aInstance, uint16_t panid)
 {
     ThreadError error = kThreadError_Busy;
diff --git a/examples/platforms/posix/radio.c b/examples/platforms/posix/radio.c
index b996e494b..fa5fb86b4 100644
--- a/examples/platforms/posix/radio.c
+++ b/examples/platforms/posix/radio.c
@@ -260,6 +260,19 @@ static inline void getExtAddress(const uint8_t *frame, otExtAddress *address)
     }
 }
 
+void otPlatRadioGetIeeeEui64(otInstance *aInstance, uint8_t *aIeeeEui64)
+{
+    (void)aInstance;
+    aIeeeEui64[0] = 0x18;
+    aIeeeEui64[1] = 0xb4;
+    aIeeeEui64[2] = 0x30;
+    aIeeeEui64[3] = 0x00;
+    aIeeeEui64[4] = (NODE_ID >> 24) & 0xff;
+    aIeeeEui64[5] = (NODE_ID >> 16) & 0xff;
+    aIeeeEui64[6] = (NODE_ID >> 8) & 0xff;
+    aIeeeEui64[7] = NODE_ID & 0xff;
+}
+
 ThreadError otPlatRadioSetPanId(otInstance *aInstance, uint16_t panid)
 {
     ThreadError error = kThreadError_Busy;
diff --git a/include/platform/radio.h b/include/platform/radio.h
index 6a336c433..32450f2fb 100644
--- a/include/platform/radio.h
+++ b/include/platform/radio.h
@@ -144,6 +144,15 @@ typedef enum PhyState
  *
  */
 
+/**
+ * Get the factory-assigned IEEE EUI-64 for this interface.
+ *
+ * @param[in]  aInstance   The OpenThread instance structure.
+ * @param[out] aIeeeEui64  A pointer to where the factory-assigned IEEE EUI-64 will be placed.
+ *
+ */
+void otPlatRadioGetIeeeEui64(otInstance *aInstance, uint8_t *aIeeeEui64);
+
 /**
  * Set the PAN ID for address filtering.
  *
diff --git a/src/cli/cli.cpp b/src/cli/cli.cpp
index 1481b31ea..a93dfddba 100644
--- a/src/cli/cli.cpp
+++ b/src/cli/cli.cpp
@@ -52,6 +52,7 @@
 #include <common/encoding.hpp>
 #include <common/new.hpp>
 #include <net/ip6.hpp>
+#include <platform/radio.h>
 #include <platform/random.h>
 #include <platform/uart.h>
 
@@ -83,6 +84,7 @@ const struct Command Interpreter::sCommands[] =
 #endif
     { "discover", &Interpreter::ProcessDiscover },
     { "eidcache", &Interpreter::ProcessEidCache },
+    { "eui64", &Interpreter::ProcessEui64 },
 #ifdef OPENTHREAD_EXAMPLES_POSIX
     { "exit", &Interpreter::ProcessExit },
 #endif
@@ -546,6 +548,22 @@ exit:
     AppendResult(kThreadError_None);
 }
 
+void Interpreter::ProcessEui64(int argc, char *argv[])
+{
+    ThreadError error = kThreadError_None;
+    otExtAddress extAddress;
+
+    VerifyOrExit(argc == 0, error = kThreadError_Parse);
+
+    otPlatRadioGetIeeeEui64(mInstance, extAddress.m8);
+    OutputBytes(extAddress.m8, OT_EXT_ADDRESS_SIZE);
+    sServer->OutputFormat("\r\n");
+
+exit:
+    (void)argv;
+    AppendResult(error);
+}
+
 void Interpreter::ProcessExtAddress(int argc, char *argv[])
 {
     ThreadError error = kThreadError_None;
diff --git a/src/cli/cli.hpp b/src/cli/cli.hpp
index 487cf456a..a107c7bf5 100644
--- a/src/cli/cli.hpp
+++ b/src/cli/cli.hpp
@@ -153,6 +153,7 @@ private:
 #endif  // OPENTHREAD_ENABLE_DIAG
     void ProcessDiscover(int argc, char *argv[]);
     void ProcessEidCache(int argc, char *argv[]);
+    void ProcessEui64(int argc, char *argv[]);
 #ifdef OPENTHREAD_EXAMPLES_POSIX
     void ProcessExit(int argc, char *argv[]);
 #endif
diff --git a/src/core/meshcop/joiner.cpp b/src/core/meshcop/joiner.cpp
index 02e76ec85..7918e250e 100644
--- a/src/core/meshcop/joiner.cpp
+++ b/src/core/meshcop/joiner.cpp
@@ -44,6 +44,8 @@
 #include <common/encoding.hpp>
 #include <common/logging.hpp>
 #include <meshcop/joiner.hpp>
+#include <platform/radio.h>
+#include <platform/random.h>
 #include <thread/thread_netif.hpp>
 #include <thread/thread_uris.hpp>
 
@@ -65,6 +67,20 @@ Joiner::Joiner(ThreadNetif &aNetif):
 ThreadError Joiner::Start(const char *aPSKd)
 {
     ThreadError error;
+    union
+    {
+        Mac::ExtAddress extAddress;
+        uint8_t buf[Crypto::Sha256::kHashSize];
+    };
+    Crypto::Sha256 sha256;
+
+    // use extended address based on factory-assigned IEEE EUI-64
+    otPlatRadioGetIeeeEui64(NULL, buf);
+    sha256.Start();
+    sha256.Update(buf, OT_EXT_ADDRESS_SIZE);
+    sha256.Finish(buf);
+    mNetif.GetMac().SetExtAddress(extAddress);
+    mNetif.GetMle().UpdateLinkLocalAddress();
 
     SuccessOrExit(error = mNetif.GetDtls().SetPsk(reinterpret_cast<const uint8_t *>(aPSKd),
                                                   static_cast<uint8_t>(strlen(aPSKd))));
@@ -268,6 +284,7 @@ void Joiner::HandleJoinerEntrust(Coap::Header &aHeader, Message &aMessage, const
     ExtendedPanIdTlv extendedPanId;
     NetworkNameTlv networkName;
     ActiveTimestampTlv activeTimestamp;
+    Mac::ExtAddress extAddress;
 
     VerifyOrExit(aHeader.GetType() == Coap::Header::kTypeConfirmable &&
                  aHeader.GetCode() == Coap::Header::kCodePost, error = kThreadError_Drop);
@@ -296,6 +313,15 @@ void Joiner::HandleJoinerEntrust(Coap::Header &aHeader, Message &aMessage, const
 
     otLogInfoMeshCoP("join success!\r\n");
 
+    // configure a random Extended Address
+    for (size_t i = 0; i < sizeof(extAddress); i++)
+    {
+        extAddress.m8[i] = static_cast<uint8_t>(otPlatRandomGet());
+    }
+
+    mNetif.GetMac().SetExtAddress(extAddress);
+    mNetif.GetMle().UpdateLinkLocalAddress();
+
 exit:
     (void)aMessageInfo;
     return;