\chapter[IP]{Internet Protocol} \section[IPv6]{Internet Protocol v6} \gls{ipv6} has recently been defined in an updated \rfc{8200} which obsoletes several of the older \gls{rfc} documents regarding \gls{ipv6}. \gls{ipv6} came about in 1998 when the original \rfc{2460} was published. It aims to provide globally route-able addresses (i.e. no need for \gls{nat}) and provides a hierarchical way to allocate address prefixes in a way which makes it simple to do route aggregation\footnote{This helps limits the size of the Internet's global routing table!}.\cite{wiki:IPv6} \wikicommons[An illustration of an example IPv6 address with leading zeros in the binary rendering]{ipv6_address_leading_zeros} \subsection{IP to client} Several ways to assign a client an address exists. \begin{itemize} \item Let the client handle it itself (i.e. \gls{dhcp} server present): \gls{slaac}. \begin{itemize} \item \gls{icmp6} router discovery messages is used to detect info 'bout the connected network segment. \item Upon \textit{link up} client sends link-local solicitation multicast req. for network parameters, \item router \textit{responds with} router adv. packet cont. \gls{ip} cfg parameters. \end{itemize} \item Let the \gls{dhcp} server assign \textit{partial} info to the client. \item Let the \gls{dhcp} server assign \textit{every} info to the client. \end{itemize} \textbf{Privacy} is a large concern regarding \gls{ipv6} because of the globally unique address the client posses. Implementation to do privacy regarding the host bits of an \gls{ip6} has been done to protect the clients (and users) from being tracked. Alas, if the \gls{isp} do static prefix assignments to end users. This privacy protection may be somewhat unusable. As the network prefix will always remain the same. Regardless of the host-bits being changed often. Have 3 different forms: \begin{enumerate} \item \texttt{2001:0db8:0000:0000:0000:ff00:0042:8329}, \item \texttt{2001:db8:0:0:0:ff00:42:8329}, {\footnotesize (i.e. remove leading zeroes per group delimited by colon)} \item \texttt{2001:db8::ff00:42:8329}. {\footnotesize (i.e. remove groups containing all zeroes in succession after each other) (only done \textit{once!}} \end{enumerate} \subsection{Packet Header} \wikicommons{Ipv6_header} \subsection{Address Types} \begin{itemize} \item \itemhead[]{Link-Local} \begin{itemize} \item Address assigned from the \texttt{fe80::/10} prefix. \item Either derived with the EUI-64\footnote{The EUI-64 involves the MAC address and injecting fffe into the middle making it 64 bits and using this as host bits} method or randomly selected. Then assigned after \gls{dad} has been run on the network segment. \item \itemhead[]{Unique Link Local}\cite{wiki:Unique_local_address} \begin{itemize} \item Defined as block \texttt{fc00::/7}. See \rfc{4193}. \item \gls{ula} is \glspl{ip6} counter-part to \glspl{ip4} \rfc{1918} address space. \item Only usable within a private network. \item Divided into 2 /8 \gls{ip6} blocks. \begin{enumerate} \item \texttt{fc00::/8} -- Not \textit{yet} officially allocated/defined by the \gls{ietf}. \item \texttt{fd00::/8} -- Defined as /48 prefixes. The last 40 bits is randomly generated and appended to the first 8 significant bits {\small (i.e. \texttt{0xFD} aka. \texttt{11111101})}. \end{enumerate} \end{itemize} \item \itemhead[]{Solicited-node multicast address} \end{itemize} \item \itemhead[]{Global Addressing} \begin{itemize} \item Address types \begin{itemize} \item Unicast: Identifies each \gls{nic}. \item Anycast: Identifies a group of \glspl{nic} belonging to the same group and providing the same services/content/applications. Nearest one to source is used. \item Multicast: Used to deliver content to multiple \glspl{nic} at once. Traffic is a single flow from the source (i.e. not multiple unicast streams). \item Broadcast: \textit{Not} implemented. Replaced by use of multicast groups. \end{itemize} \end{itemize} \end{itemize} \subsection{AAAA} \gls{dns6} had 2 running proposals when first proposed, \rfc{2874} (1st), \rfc{3364} (later discussion), and \rfc{3363} thou deprecated this proposal to experimental status. The winning one was \rfc{3596} with the idea of doing \textit{quad}-A records and hierarchically divided by \textit{nibble} {\small (i.e. 4 bits)}. The idea is fx. \texttt{2001:db8:ef::2} is noted in ip6.arpa as \texttt{2.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.f.e.0.0.8.b.d.0.1.0.0.2.ip6.arpa}. {\small Note the used of '.' between \textit{each} \textit{hexadecimal} character used, and that \textit{all zeroes} has been included. ip6.arpa does not allow any characters to be omitted from the original full-length \gls{ip6} address.}\footnote{Found description \href{https://stackoverflow.com/q/6619682}{here} on stackoverflow.com/q/6619682.} \section[IPv4]{Internet Protocol v4}