diff -r cef1e8c17560 src/spectrum/model/aloha-noack-net-device.cc
--- a/src/spectrum/model/aloha-noack-net-device.cc	Fri Oct 21 15:35:22 2011 +0200
+++ b/src/spectrum/model/aloha-noack-net-device.cc	Fri Oct 21 07:22:50 2011 -0700
@@ -29,6 +29,7 @@
 #include "ns3/trace-source-accessor.h"
 #include "aloha-noack-mac-header.h"
 #include "aloha-noack-net-device.h"
+#include "spectrum-phy.h"
 #include "ns3/llc-snap-header.h"
 
 NS_LOG_COMPONENT_DEFINE ("AlohaNoackNetDevice");
@@ -82,7 +83,7 @@
                    PointerValue (),
                    MakePointerAccessor (&AlohaNoackNetDevice::GetPhy,
                                         &AlohaNoackNetDevice::SetPhy),
-                   MakePointerChecker<Object> ())
+                   MakePointerChecker<SpectrumPhy> ())
     .AddTraceSource ("MacTx",
                      "Trace source indicating a packet has arrived for transmission by this device",
                      MakeTraceSourceAccessor (&AlohaNoackNetDevice::m_macTxTrace))
@@ -248,14 +249,14 @@
 }
 
 void
-AlohaNoackNetDevice::SetPhy (Ptr<Object> phy)
+AlohaNoackNetDevice::SetPhy (Ptr<SpectrumPhy> phy)
 {
   NS_LOG_FUNCTION (this << phy);
   m_phy = phy;
 }
 
 
-Ptr<Object>
+Ptr<SpectrumPhy>
 AlohaNoackNetDevice::GetPhy () const
 {
   NS_LOG_FUNCTION (this);
diff -r cef1e8c17560 src/spectrum/model/aloha-noack-net-device.h
--- a/src/spectrum/model/aloha-noack-net-device.h	Fri Oct 21 15:35:22 2011 +0200
+++ b/src/spectrum/model/aloha-noack-net-device.h	Fri Oct 21 07:22:50 2011 -0700
@@ -40,6 +40,7 @@
 class Channel;
 class SpectrumErrorModel;
 class Queue;
+class SpectrumPhy;
 
 
 
@@ -131,18 +132,14 @@
    * This object is needed so that we can set/get attributes and
    * connect to trace sources of the PHY from the net device.
    *
-   * @param phy the Phy object attached to the device.  Note that the
-   * API between the PHY and the above (this NetDevice which also
-   * implements the MAC) is implemented entirely by
-   * callbacks, so we do not require that the PHY inherits by any
-   * specific class.
+   * @param phy the Phy object attached to the device.  
    */
-  void SetPhy (Ptr<Object> phy);
+  void SetPhy (Ptr<SpectrumPhy> phy);
 
   /**
    * @return a reference to the PHY object embedded in this NetDevice.
    */
-  Ptr<Object> GetPhy () const;
+  Ptr<SpectrumPhy> GetPhy () const;
 
 
 
@@ -221,7 +218,7 @@
 
   Ptr<Packet> m_currentPkt;
 
-  Ptr<Object> m_phy;
+  Ptr<SpectrumPhy> m_phy;
 };
 
 
diff -r cef1e8c17560 src/spectrum/model/non-communicating-net-device.cc
--- a/src/spectrum/model/non-communicating-net-device.cc	Fri Oct 21 15:35:22 2011 +0200
+++ b/src/spectrum/model/non-communicating-net-device.cc	Fri Oct 21 07:22:50 2011 -0700
@@ -27,6 +27,7 @@
 #include "ns3/pointer.h"
 #include "ns3/channel.h"
 #include "non-communicating-net-device.h"
+#include "spectrum-phy.h"
 
 
 NS_LOG_COMPONENT_DEFINE ("NonCommunicatingNetDevice");
@@ -48,7 +49,7 @@
                    PointerValue (),
                    MakePointerAccessor (&NonCommunicatingNetDevice::GetPhy,
                                         &NonCommunicatingNetDevice::SetPhy),
-                   MakePointerChecker<Object> ())
+                   MakePointerChecker<SpectrumPhy> ())
   ;
   return tid;
 }
@@ -181,14 +182,14 @@
 }
 
 void
-NonCommunicatingNetDevice::SetPhy (Ptr<Object> phy)
+NonCommunicatingNetDevice::SetPhy (Ptr<SpectrumPhy> phy)
 {
   NS_LOG_FUNCTION (this << phy);
   m_phy = phy;
 }
 
 
-Ptr<Object>
+Ptr<SpectrumPhy>
 NonCommunicatingNetDevice::GetPhy () const
 {
   NS_LOG_FUNCTION (this);
diff -r cef1e8c17560 src/spectrum/model/non-communicating-net-device.h
--- a/src/spectrum/model/non-communicating-net-device.h	Fri Oct 21 15:35:22 2011 +0200
+++ b/src/spectrum/model/non-communicating-net-device.h	Fri Oct 21 07:22:50 2011 -0700
@@ -37,6 +37,7 @@
 class Channel;
 class SpectrumErrorModel;
 class Queue;
+class SpectrumPhy;
 
 
 
@@ -79,12 +80,12 @@
    *
    * @param phy the Phy object embedded within this device.
    */
-  void SetPhy (Ptr<Object> phy);
+  void SetPhy (Ptr<SpectrumPhy> phy);
 
   /**
    * @return a reference to the PHY object embedded in this NetDevice.
    */
-  Ptr<Object> GetPhy () const;
+  Ptr<SpectrumPhy> GetPhy () const;
 
 
 
@@ -128,7 +129,7 @@
 
   uint32_t m_ifIndex;
 
-  Ptr<Object> m_phy;
+  Ptr<SpectrumPhy> m_phy;
 };