diff --git a/interest.rst b/interest.rst
index 87faf10..7b5a263 100644
--- a/interest.rst
+++ b/interest.rst
@@ -1,9 +1,11 @@
-.. _interest:
+.. _Interest:
 
 Interest Packet
 ---------------
 
-NDN Interest packet is TLV defined as follows::
+NDN Interest packet is TLV defined as follows:
+
+::
 
     Interest ::= INTEREST-TYPE TLV-LENGTH 
                    Name
@@ -12,16 +14,6 @@
                    Scope?
                    InterestLifetime?
 
-Selectors::
-
-    Selectors ::= SELECTORS-TYPE TLV-LENGTH 
-                    MinSuffixComponents?
-                    MaxSuffixComponents?
-                    PublisherPublicKeyLocator?
-                    Exclude?
-                    ChildSelector?
-                    MustBeFresh?
-
 ``Name`` and ``Nonce`` are the only two two required elements in an Interest packet.
 Selectors are optional elements that further qualify Data that may match the Interest.
 They are used for discovering and selecting the Data that matches best to what the application wants. Selectors are placed right after the Name to facilitate implementations that may use continuous memory block of Name and Selectors TLVs together as the index for PIT lookup. By using a TLV to group all the Selectors, an implementation can easily skip them to find Nonce, which is used together with Name to identify looping Interests. 
@@ -34,24 +26,43 @@
 Name
 ~~~~
 
-The Name element in an Interest is synonymous with the term *prefix*. See :ref:`Name section<name>` for details.
-  
+The Name element in an Interest is synonymous with the term *prefix*.
+See :ref:`Name section <Name>` for details.
+
+.. _Nonce:
+
 Nonce
 ~~~~~
 
-Nonce defined as follows::
+Nonce defined as follows:
 
-    Nonce ::= NONCE-TYPE TLV-LENGTH BYTE+
+::
 
-The Nonce carries a randomly-genenerated byte-string. The combination of Name and Nonce should uniquely identify an Interest packet. This is used to detect looping Interests\footnote{We plan to select a recommended length for Nonce in next revision.}.
+    Nonce ::= NONCE-TYPE TLV-LENGTH(=4) BYTE{4}
+
+The Nonce carries a randomly-genenerated 4-octet long byte-string.
+The combination of Name and Nonce should uniquely identify an Interest packet.
+This is used to detect looping Interests.
+
+.. _Selectors:
 
 Selectors
 ~~~~~~~~~
-  
+
+::
+
+    Selectors ::= SELECTORS-TYPE TLV-LENGTH 
+                    MinSuffixComponents?
+                    MaxSuffixComponents?
+                    PublisherPublicKeyLocator?
+                    Exclude?
+                    ChildSelector?
+                    MustBeFresh?
+
 MinSuffixComponents, MaxSuffixComponents
 ++++++++++++++++++++++++++++++++++++++++
 
-.. code-block:: none
+::
 
     MinSuffixComponents ::= MIN-SUFFIX-COMPONENTS-TYPE TLV-LENGTH
                               nonNegativeInteger
@@ -67,7 +78,7 @@
 PublisherPublicKeyLocator
 +++++++++++++++++++++++++
 
-.. code-block:: none
+::
 
     PublisherPublicKeyLocator ::= PUBLISHER-PUBLIC-KEY-TYPE TLV-LENGTH Name
 
@@ -77,7 +88,7 @@
 Exclude
 +++++++
 
-.. code-block:: none
+::
 
     Exclude ::= EXCLUDE-TYPE TLV-LENGTH Any? (NameComponent (Any)?)+
     Any ::= ANY-TYPE TLV-LENGTH(=0)
@@ -98,13 +109,13 @@
 - If ``Any`` component is specified between two NameComponents in the list, then the filter excludes all names from the range from the right NameComponent to the left NameComponent, including both ends.
 
 
-Exclude filter MUST not consist of a single ``Any`` component or one NameComponent with leading and trailing ``Any'' components.
+Exclude filter MUST not consist of a single ``Any`` component or one NameComponent with leading and trailing ``Any`` components.
 
 
 ChildSelector
 +++++++++++++
 
-.. code-block:: none
+::
 
     ChildSelector ::= CHILD-SELECTOR-TYPE TLV-LENGTH 
                         nonNegativeInteger
@@ -122,7 +133,7 @@
 MustBeFresh
 +++++++++++
 
-.. code-block:: none
+::
 
    MustBeFresh ::= MUST-BE-FRESH-TYPE TLV-LENGTH(=0)
 
@@ -135,7 +146,7 @@
 Scope
 +++++
 
-.. code-block:: none
+::
 
     Scope ::= SCOPE-TYPE TLV-LENGTH nonNegativeInteger
 
@@ -149,7 +160,7 @@
 InterestLifetime
 ++++++++++++++++
 
-.. code-block:: none
+::
 
     InterestLifetime ::= INTEREST-LIFETIME-TYPE TLV-LENGTH nonNegativeInteger