I can feel it.... :)

Binh.

LDP/guide/docbook/Linux-Networking/Feedback.xml

@@ -8,7 +8,7 @@
   been made to ensure that the instructions and information herein are 
   accurate and reliable. Send comments, corrections, suggestions and questions 
   to the author Binh Nguyen, linuxfilesystem(at)yahoo(dot)com(dot)au with the
-  subject heading of Linux Networking. There is however, no guarantee of response.
+  subject heading of 'Linux Networking'. There is however, no guarantee of response.
   </para>
   
   <para>

LDP/guide/docbook/Linux-Networking/Layering.xml

@@ -92,6 +92,8 @@ There are eight main network technology issues that must be addressed at each la
 in the architecture though. These are outlined below:
 </para>
 
+<para>
+<screen>
 1. Mechanism of identifying senders and receivers: addressing.
 2. Rules for data transfer: simplex, half-duplex, or full-duplex.
 3. Logical channels: sharing a link among a number of connections.
@@ -100,6 +102,8 @@ in the architecture though. These are outlined below:
 6. Incompatible speed between fast sender and slow receiver.
 7. Message fragmentation and assembly.
 8. Strategies for choosing routes.
+</screen>
+</para>
 
 <para>
 To study the above issues in detail please consult, Tannenbaum 4th edition.
@@ -121,35 +125,41 @@ and their respective functions and services.
 </para>
 
 
-<para><variablelist>
+<para>
+<screen>
+entity:
+in software, it is sometimes called a process;
+in hardware in hardware it could mean in pratice an I/O chip
 
-<varlistentry><term>entity:</term>
+peer enties:
-<listitem><para>in software, it is sometimes called a process; in hardware in hardware it could mean in pratice an I/O chip</para></listitem></varlistentry>
+entities at the same layer in different machines/devices
 
-<varlistentry><term>peer enties:</term>
+service provider: 
-<listitem><para>entities at the same layer in different machines/devices</para></listitem></varlistentry>
+eg. layer n, a layer that provides a service
-<varlistentry><term>service provider:</term> 
-<listitem><para>eg. layer n, a layer that provides a service</para></listitem></varlistentry>
 
-<varlistentry><term>service receiver:</term>
+service receiver:
-<listitem><para>eg. layer n + 1, a layer that receives a service</para></listitem></varlistentry>
+eg. layer n + 1, a layer that receives a service
 
-<varlistentry><term>service access point (SAP):</term>
+service access point (SAP):
-<listitem><para>a point where service is accessed, for example a function call in software, or the telephone for a telephone company</para></listitem></varlistentry>
+a point where service is accessed, for example a function call
+in software, or the telephone for a telephone company
 
-<varlistentry><term>protocol data unit (PDU):</term>
+protocol data unit (PDU):
-<listitem><para>a data unit that is communicated between peer entities</para></listitem></varlistentry>
+a data unit that is communicated between peer entities
 
-<varlistentry><term>service data unit (SDU):</term>
+service data unit (SDU):
-<listitem><para>the PDU from the serice receiver</para></listitem></varlistentry>
+the PDU from the serice receiver
 
-<varlistentry><term>protocol control information (PCI):</term>
+protocol control information (PCI):
-<listitem><para>is appended by a service receiver to an SDU in order to indicated the type of service required and forms the IDU</para></listitem></varlistentry>
+is appended by a service receiver to an SDU in order to
+indicated the type of service required and forms the IDU
 
-<varlistentry><term>interface data unit (IDU):</term>
+interface data unit (IDU):
-<listitem><para>the data unit that is given from a service receiver to a service provider.</para></listitem></varlistentry>
+the data unit that is given from a service receiver to a
+service provider.
 
-</variablelist></para>
+</screen>
+</para>
 
 <para>
 The term "service" can be deemed to mean a number of things. These are outlined
@@ -184,24 +194,24 @@ the service interface. The primitives differ for different services. As a simple
 example, a service may provide the following primitives:
 </para>
 
-<para><orderedlist>
+<para>
+<screen>
+LISTEN:
+listen for an incoming communication request
 
-<varlistentry><term>LISTEN:</term>
+CONNECT:
-<listitem><para>listen for an incoming communication request</para></listitem></varlistentry>
+make a communication request
 
-<varlistentry><term>CONNECT:</term>
+RECEIVE:
-<listitem><para>make a communication request</para></listitem></varlistentry>
+receive data of a communication
 
-<varlistentry><term>RECEIVE:</term>
+SEND:
-<listitem><para>receive data of a communication</para></listitem></varlistentry>
+send data of a communication
 
-<varlistentry><term>SEND:</term>
+DISCONNECT:
-<listitem><para>send data of a communication</para></listitem></varlistentry>
+disconnect or discontinue a communication
-
+</screen>
-<varlistentry><term>DISCONNECT:</term>
+</para>
-<listitem><para>disconnect or discontinue a communication</para></listitem></varlistentry>
-
-</orderedlist></para>
 
 <para>
 As discussed before, each layer has specfic functions and offers certain services