diff --git a/acronyms.tex b/acronyms.tex
index e9efbd3..cf5fbf6 100644
--- a/acronyms.tex
+++ b/acronyms.tex
@@ -20,22 +20,25 @@
 \newacronym{dhcp}{DHCP}{Dynamic Host Control Protocol}
 \newacronym{dknog}{DKNOG}{Danish Network Operators' Group}
 \newacronym{dns}{DNS}{Domain Name System}
-\newacronym{dst}{DST}{Destination}
+\newacronym{dst}{dst}{destination}
 \newacronym{dwdm}{DWDM}{}
 \newacronym{eap}{EAP}{Extensible Authentication Protocol}
-\newacronym{eapol}{EAPOL}{Extensible Authentication Protocol over Local Area Network}
+\newacronym{eapol}{EAPoL}{Extensible Authentication Protocol over Local Area Network}
 \newacronym{eigrp}{EIGRP}{Enhanced Interior Gateway Routing Protocol}
 \newacronym{evpn}{EVPN}{Ethernet Virtual Private Network}
 \newacronym{ftp}{FTP}{File Transfer Protocol}
 \newacronym{ftps}{FTPS}{File Transfer Protocol Secure}
+\newacronym{gps}{GPS}{Global Positioning System}
+\newacronym{gprs}{GPRS}{General Packet Radio Service}
+\newacronym{gsm}{GSM}{Global System for Mobile communications}
 \newacronym{ieee}{IEEE}{Institute of Electrical and Electronics Engineers}
 \newacronym{igrp}{IGRP}{Interior Gateway Routing Protocol}
 \newacronym{imap}{IMAP}{Internet Message Access Protocol}
 \newacronym{ip}{IP}{Internet Protocol}
-\newacronym{ipv4}{IPV4}{Internet Protocol v4}
-\newacronym{ipv6}{IPV6}{Internet Protocol v6}
+\newacronym{ipv4}{IPv4}{Internet Protocol v4}
+\newacronym{ipv6}{IPv6}{Internet Protocol v6}
 \newacronym{irc}{IRC}{Internet Relay Chat}
-\newacronym{isis}{ISIS}{Intermediate System to Intermediate System}
+\newacronym{isis}{IS-IS}{Intermediate System to Intermediate System}
 \newacronym{isp}{ISP}{Internet Service Provider}
 \newacronym{l2}{L2}{Layer 2}
 \newacronym{l2vpn}{L2VPN}{Layer 2 Virtual Private Network}
@@ -43,15 +46,15 @@
 \newacronym{lacp}{LACP}{Link Aggregation Protocol}
 \newacronym{lan}{LAN}{Local Area Network}
 \newacronym{mac}{MAC}{Media Access Control address}
-\newacronym{metdst}{METDST}{Middle European Time Daylight Saving Time}
+\newacronym{metdst}{MET-DST}{Middle European Time Daylight Saving Time}
 \newacronym{mkc}{MKC}{Mikkel Krĝll}
 \newacronym{mpls}{MPLS}{Multiprotocol Label Switching}
 \newacronym{mst}{MST}{Multiple Spanning Tree}
 \newacronym{ntp}{NTP}{Network Time Protocol}
 \newacronym{osi}{OSI}{Open Systems Interconnection}
 \newacronym{ospf}{OSPF}{Open Shortest Path First}
-\newacronym{ospfv3}{OSPFV3}{Open Shortest Path First v3}
-\newacronym{pagp}{PAGP}{Port Aggregation Protocol}
+\newacronym{ospfv3}{OSPFv3}{Open Shortest Path First v3}
+\newacronym{pagp}{PAgP}{Port Aggregation Protocol}
 \newacronym{pop3}{POP3}{Post Office Protocol}
 \newacronym{pvrst}{PVRST}{Per Vlan Rapid Spanning Tree}
 \newacronym{pvrst+}{PVRST+}{Per Vlan Rapid Spanning Tree Plus}
@@ -68,13 +71,13 @@
 \newacronym{snmp}{SNMP}{Simple Network Management Protocol}
 \newacronym{sntp}{SNTP}{Secure Network Time Protocol}
 \newacronym{sp}{SP}{Service Provider}
-\newacronym{src}{SRC}{Source}
+\newacronym{src}{src}{source}
 \newacronym{ssh}{SSH}{Secure Shell}
 \newacronym{stp}{STP}{Spanning Tree Protocol}
 \newacronym{tcn}{TCN}{Topology Change Notification}
 \newacronym{tcp}{TCP}{Transmission Control Protocol}
 \newacronym{tftp}{TFTP}{Trivial File Transfer Protocol}
-\newacronym{toc}{TOC}{Table Of Contents}
+\newacronym{toc}{ToC}{Table of Contents}
 \newacronym{udld}{UDLD}{Unidirectional Link Detection}
 \newacronym{udp}{UDP}{User Datagram Protocol}
 \newacronym{utc}{UTC}{Coordinated Universal Time}
diff --git a/chapter/ntp.tex b/chapter/ntp.tex
index 2ae37b3..2fd4f4a 100644
--- a/chapter/ntp.tex
+++ b/chapter/ntp.tex
@@ -16,7 +16,28 @@ service timestamps debug datetime msec localtime show-timezone
 service timestamps log datetime msec localtime show-timezone
 \end{txt}
 
+\fig{ntp/ntp}{ntp}{\gls{ntp}}
+
+\gls{ntp} servers are a hierarchical tree with stratum 0 servers as the authoritative in the tree. These servers get their time from either \gls{gprs} satellites or atomic clocks {\footnotesize (i.e. an authoritative time \gls{src})}.
+
+\subsection{Characteristics}
+
+\begin{itemize}
+	\item Uses \gls{udp} port 123 on both \gls{src} and \gls{dst},
+	\item polling interval ranging from 64-1024 sec. Length of interval is dependant upon network cond.,
+	\item large differences between \gls{ntp} reference time and local client time will result in increased pooling interval.
+\end{itemize}
+
+\fig{ntp/ntpstratum}{ntpstratum}{Stratum levels}
+
+
+
 \section{The old NTP from \tsq{85}}
 
 \section{Secure NTP}
 
+\subsection{Characteristics}
+
+\begin{itemize}
+	\item 
+\end{itemize}
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