Initial chapter dhcp

chapter/layer3protocols.tex

@@ -2,6 +2,10 @@
 
 \input{chapter/section/intervlanrouting}
 
+\chapter{DHCP}
+
+\input{chapter/section/dhcp}
+
 \chapter{Protocols Layer 3}
 
 \input{chapter/section/routednetwork}

chapter/section/dhcp.tex

@@ -0,0 +1,33 @@
+\section{Process}
+
+\fig{dhcp/dhcpdiscoverprocess}{dhcpdiscoverprocess}{DHCP Discover Process}
+
+\subsection{DHCP Messages}
+
+\begin{itemize}
+    \item \textbf{DHCPDECLINE:} Message sent from the client to the server that the address is already in use.
+    \item \textbf{DHCPNAK:} The server sends a refusal to the client for request for configuration.
+    \item \textbf{DHCPRELEASE:} Client tells a server that it is giving up a lease.
+    \item \textbf{DHCPINFORM:} A client already has an IP address but is requesting other configuration parameters that the DHCP server is configured to deliver such as DNS address.
+\end{itemize}
+
+\section{Example configuration}
+
+\subsection{Cisco}
+
+\begin{txt}
+ip dhcp excluded-address 192.168.0.254
+!
+ip dhcp pool LAN-1-POOL-DHCP
+ network 192.168.0.0 255.255.255.0
+ default-router 192.168.0.254
+ lease 2 ! set in days
+\end{txt}
+
+When configuring a Layer 3 interface as a relay port for DHCP request for a subnet. Set the ip helper command on the interface with one \textit{or} more ip addresses.
+
+\begin{txt}
+interface GigabitEthernet 0/3
+ ip helper-address 192.168.220.220
+ ip helper-address 192.168.222.222
+\end{txt}