model: Initial attempt to optimize Interest/Data encoding/decoding via a custom packet format
diff --git a/model/ndn-interest-header.cc b/model/ndn-interest-header.cc
index d0ebaab..f128821 100644
--- a/model/ndn-interest-header.cc
+++ b/model/ndn-interest-header.cc
@@ -15,21 +15,14 @@
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  *
- * Author: Ilya Moiseenko <iliamo@cs.ucla.edu>
- *         Alexander Afanasyev <alexander.afanasyev@ucla.edu>
+ * Author: Alexander Afanasyev <alexander.afanasyev@ucla.edu>
  */
 
-///< #CCN_PR_SCOPE0 (0x20) local scope,
-///< #CCN_PR_SCOPE1 (0x40) this host,
-///< #CCN_PR_SCOPE2 (0x80) immediate neighborhood
-
 #include "ndn-interest-header.h"
 
 #include "ns3/log.h"
 #include "ns3/unused.h"
 #include "ns3/packet.h"
-#include "../helper/ndn-encoding-helper.h"
-#include "../helper/ndn-decoding-helper.h"
 
 NS_LOG_COMPONENT_DEFINE ("ndn.InterestHeader");
 
@@ -52,12 +45,7 @@
 
 InterestHeader::InterestHeader ()
   : m_name ()
-  , m_minSuffixComponents (-1)
-  , m_maxSuffixComponents (-1)
-  , m_exclude ()
-  , m_childSelector (false)
-  , m_answerOriginKind (false)
-  , m_scope (-1)
+  , m_scope (0xFF)
   , m_interestLifetime (Seconds (0))
   , m_nonce (0)
   , m_nackType (NORMAL_INTEREST)
@@ -66,11 +54,6 @@
 
 InterestHeader::InterestHeader (const InterestHeader &interest)
   : m_name                (Create<NameComponents> (interest.GetName ()))
-  , m_minSuffixComponents (interest.m_minSuffixComponents)
-  , m_maxSuffixComponents (interest.m_maxSuffixComponents)
-  , m_exclude             (interest.IsEnabledExclude () ? Create<NameComponents> (interest.GetExclude ()) : 0)
-  , m_childSelector       (interest.m_childSelector)
-  , m_answerOriginKind    (interest.m_answerOriginKind)
   , m_scope               (interest.m_scope)
   , m_interestLifetime    (interest.m_interestLifetime)
   , m_nonce               (interest.m_nonce)
@@ -107,73 +90,6 @@
 }
 
 void
-InterestHeader::SetMinSuffixComponents (int32_t value)
-{
-  m_minSuffixComponents = value;
-}
-
-int32_t
-InterestHeader::GetMinSuffixComponents () const
-{
-  return m_minSuffixComponents;
-}
-
-void
-InterestHeader::SetMaxSuffixComponents (int32_t value)
-{
-  m_maxSuffixComponents = value;
-}
-
-int32_t
-InterestHeader::GetMaxSuffixComponents () const
-{
-  return m_maxSuffixComponents;
-}
-
-void
-InterestHeader::SetExclude (Ptr<NameComponents> exclude)
-{
-  m_exclude = exclude;
-}
-
-bool
-InterestHeader::IsEnabledExclude () const
-{
-  return m_exclude!=0;
-}
-
-const NameComponents&
-InterestHeader::GetExclude () const
-{
-  if (m_exclude==0) throw InterestHeaderException();
-  return *m_exclude;
-}
-
-void
-InterestHeader::SetChildSelector (bool value)
-{
-  m_childSelector = value;
-}
-
-bool
-InterestHeader::IsEnabledChildSelector () const
-{
-  return m_childSelector;
-}
-
-void
-InterestHeader::SetAnswerOriginKind (bool value)
-{
-  m_answerOriginKind = value;
-}
-
-bool
-InterestHeader::IsEnabledAnswerOriginKind () const
-{
-  return m_answerOriginKind;
-}
-
-void
 InterestHeader::SetScope (int8_t scope)
 {
   m_scope = scope;
@@ -210,12 +126,12 @@
 }
 
 void
-InterestHeader::SetNack (uint32_t nackType)
+InterestHeader::SetNack (uint8_t nackType)
 {
   m_nackType = nackType;
 }
 
-uint32_t
+uint8_t
 InterestHeader::GetNack () const
 {
   return m_nackType;
@@ -224,22 +140,61 @@
 uint32_t
 InterestHeader::GetSerializedSize (void) const
 {
-  // unfortunately, we don't know exact header size in advance
-  return EncodingHelper::GetSerializedSize (*this);
+  size_t size = 2 + (1 + 4 + 2 + 1 + (m_name->GetSerializedSize ()) + (2 + 0) + (2 + 0));
+  NS_LOG_INFO ("Serialize size = " << size);
+
+  return size;
 }
     
 void
 InterestHeader::Serialize (Buffer::Iterator start) const
 {
-  size_t size = EncodingHelper::Serialize (start, *this);
-  NS_UNUSED (size);
-  NS_LOG_INFO ("Serialize size = " << size);
+  start.WriteU8 (0x80); // version
+  start.WriteU8 (0x00); // packet type
+
+  start.WriteU32 (m_nonce);
+  start.WriteU8 (m_scope);
+  start.WriteU8 (m_nackType);
+
+  NS_ASSERT_MSG (0 <= m_interestLifetime.ToInteger (Time::S) && m_interestLifetime.ToInteger (Time::S) < 65535,
+                 "Incorrect InterestLifetime (should not be smaller than 0 and larger than 65535");
+  
+  // rounding timestamp value to seconds
+  start.WriteU16 (static_cast<uint16_t> (m_interestLifetime.ToInteger (Time::S)));
+
+  uint32_t offset = m_name->Serialize (start);
+  start.Next (offset);
+  
+  start.WriteU16 (0); // no selectors
+  start.WriteU16 (0); // no options
 }
 
 uint32_t
 InterestHeader::Deserialize (Buffer::Iterator start)
 {
-  return DecodingHelper::Deserialize (start, *this); // \todo Debugging is necessary
+  Buffer::Iterator i = start;
+  
+  if (i.ReadU8 () != 0x80)
+    throw new InterestHeaderException ();
+
+  if (i.ReadU8 () != 0x00)
+    throw new InterestHeaderException ();
+
+  m_scope = i.ReadU8 ();
+  m_nackType = i.ReadU8 ();
+  m_interestLifetime = Seconds (i.ReadU16 ());
+
+  m_name = Create<NameComponents> ();
+  uint32_t offset = m_name->Deserialize (start);
+  i.Next (offset);
+  
+  i.ReadU16 ();
+  i.ReadU16 ();
+
+  NS_ASSERT (GetSerializedSize () == (i.GetDistanceFrom (start)));
+
+  return i.GetDistanceFrom (start);
+  // return DecodingHelper::Deserialize (start, *this); // \todo Debugging is necessary
 }
 
 TypeId
@@ -272,18 +227,7 @@
         }
       os << "</NACK>\n";
     }
-  if (GetMinSuffixComponents () >= 0)
-    os << "  <MinSuffixComponents>" << GetMinSuffixComponents () << "</MinSuffixComponents>\n";
-  if (GetMaxSuffixComponents () >= 0)
-    os << "  <MaxSuffixComponents>" << m_maxSuffixComponents << "</MaxSuffixComponents>\n";
-  if (IsEnabledExclude () && GetExclude ().size()>0)
-    os << "  <Exclude>" << GetExclude () << "</Exclude>\n";
-  if (IsEnabledChildSelector ())
-    os << "  <ChildSelector />\n";
-  if (IsEnabledAnswerOriginKind ())
-    os << "  <AnswerOriginKind />\n";
-  if (GetScope () >= 0)
-    os << "  <Scope>" << GetScope () << "</Scope>\n";
+  os << "  <Scope>" << GetScope () << "</Scope>\n";
   if ( !GetInterestLifetime ().IsZero() )
     os << "  <InterestLifetime>" << GetInterestLifetime () << "</InterestLifetime>\n";
   if (GetNonce ()>0)