Merge branch '1-bgp-section'

acronyms.tex

@@ -36,6 +36,7 @@
 \newacronym{dwdm}{DWDM}{}
 \newacronym{eap}{EAP}{Extensible Authentication Protocol}
 \newacronym{eapol}{EAPoL}{Extensible Authentication Protocol over Local Area Network}
+\newacronym{ebgp}{eBGP}{Externel Border Gateway Protocol}
 \newacronym{ecn}{ECN}{Explicit Congestion Notification}
 \newacronym{eff}{EFF}{Electronic Frontier Foundation}
 \newacronym{eigrp}{EIGRP}{Enhanced Interior Gateway Routing Protocol}
@@ -62,11 +63,13 @@
 \newacronym{https}{HTTPS}{Hyper Text Transfer Protocol Secure}
 \newacronym{iab}{IAB}{Internet Architecture Board}
 \newacronym{iana}{IANA}{Internet Assigned Numbers Authority}
+\newacronym{ibgp}{iBGP}{Internal Border Gateway Protocol}
 \newacronym{icann}{ICANN}{Internet Corporation for Assigned Names and Numbers}
 \newacronym{icmp}{ICMP}{Internet Control Message Protocoll}
 \newacronym{icmp6}{ICMPv6}{Internet Control Message Protocol version 6}
 \newacronym{ieee}{IEEE}{Institute of Electrical and Electronics Engineers}
 \newacronym{ietf}{IETF}{Internet Engineering Task Force}
+\newacronym{igp}{IGP}{Interior Gateway Protocol}
 \newacronym{igrp}{IGRP}{Interior Gateway Routing Protocol}
 \newacronym{imap}{IMAP}{Internet Message Access Protocol}
 \newacronym{ios}{IOS}{Internetwork Operating System}
@@ -131,6 +134,7 @@
 \newacronym{ros}{ROS}{MikroTik RouterOS}
 \newacronym{rpr}{RPR}{Route Processor Redundancy}
 \newacronym{rpr+}{RPR+}{Route Processor Redundancy Plus}
+\newacronym{rr}{RR}{Route Reflector}
 \newacronym{rspan}{RSPAN}{Remote Switch Port Analyser}
 \newacronym{rstp}{RSTP}{Rapid Spanning Tree Protocol}
 \newacronym{rpvst}{RPVST}{Per Vlan Rapid Spanning Tree}
@@ -160,6 +164,7 @@
 \newacronym{tlv}{TLV}{Type, Length, Value}
 \newacronym{toc}{ToC}{Table of Contents}
 \newacronym{tosdr}{ToS;DR}{Terms of Service; Didn't Read}
+\newacronym{ttl}{TTL}{Time-to-live}
 \newacronym{udld}{UDLD}{Unidirectional Link Detection}
 \newacronym{udp}{UDP}{User Datagram Protocol}
 \newacronym{ula}{ULA}{Unique Local Address}

chapter/layer3.tex

@@ -7,6 +7,9 @@
 \section{EIGRP}
 \section{RIP}
 \section{Static}
+
+\newpage
+
 \section{BGP}
 
 \wikicommons{BGP_FSM}
@@ -14,38 +17,93 @@
 The protocol of the internet used since 1994.\cite{wiki:Border_Gateway_Protocol}
 Currently based upon \rfc{4271} with updates following in \rfc{6286} \rfc{6608}, \rfc{6793}, \rfc{7606}, \rfc{7607}, \rfc{7705}.
 
-
+\subsection{Properties}
 
 \begin{itemize}
-    \item \itemhead{Properties}
-    \begin{itemize}
     \item Uses tcp/179 as \gls{dst} port
     \item Sends keep-alive message every 1 minute
-        \item Keep-alive message is 19 byte
+    \item Keep-alive message is 19 byte long
-    \end{itemize}
+\end{itemize}
-    \item \itemhead{Route exchange}
+
-    \begin{itemize}
+Be ware if sessions are terminated immediately upon trying to establish connection. Try debugging following points.
-        \item \itemhead{Route-maps mechanism}
+
-        \begin{itemize}
+\begin{itemize}
-            \item Routes can be aggregated between \Glspl{as}.
+    \item tcp/179 is not open,
-            \item Properties can be changed on the fly by mathing
+    \item random port 1023> is not open,
+    \item incorrect peer-ip,
+    \item incorrect peer-as.
+\end{itemize}
+
+\subsection{Route exchange}
+
+Exchanging routes between routers is a reliant and tolerant manner is \glspl{bgp} 1-advantage over \gls{ospf}/\gls{isis}/\gls{rip}/\gls{eigrp}.
+
+The sheer tuning and control mechanisms \gls{bgp} can offer is simply astounding. Route-maps is the key and access-lists just one option.
+
+\subsubsection[Route-maps]{Route-maps mechanism}
+
+Route-maps is used to target a select set of routes and either modify/add/remove attributes attached to the select route-set.
+
+\begin{itemize}
+    \item Routes can be aggregated between \glspl{as}.
+    \item Properties can be changed on the fly by matching
     \begin{enumerate}[label={\alph*)}]
         \item \Gls{bgp} communities,
         \item \Gls{ip} prefix,
         \item \Gls{bgp} as-path, 
     \end{enumerate}
-        \end{itemize}
+\end{itemize}
-        \item 
+
-    \end{itemize}
+An simple example of using route-maps is
-    \item \itemhead{States}
+
-    \begin{enumerate}
+\begin{cisco}
-        \item Idle: \Gls{bgp} while initializing refuses all incoming connections. Will initiate \Gls{tcp} connection to peer.
+ip prefix-list 1 permit 172.16.0.0/16 
-        \item Connect: Waits for \Gls{tcp} connection. If \Gls{tcp} is established goes to state OpenSent. If \Gls{tcp} is \textit{un}successful ConnectRetry timer is started and then goes to Active state.
+ip prefix-list 2 permit 192.168.1.0/24 
+!
+route-map RED permit 10 
+ match ip address prefix-list 1 
+ set ip next hop 10.1.1.1
+ continue 20              ! Continues to apply rules normally only
+                          ! applied to prefix-list 2. To apply to
+                          ! prefix-list 1, too.
+                          ! Any attributes set in '20' will
+                          ! override any set during '10'.
+route-map RED permit 20 
+ match ip address prefix-list 2 
+ set ip next hop 10.2.2.2 ! Last rule overrides previous rules from
+                          ! previous '10' rule-set.
+\end{cisco}
+
+When rules from a rule-set is chained together as shown above. The last rule will override all previous set values regarding the attribute being applied. In this case \texttt{next-hop} from 'permit 10' is overridden in 'permit 20'.
+
+\subsection[States]{BGP States}
+
+The states is the way \gls{bgp} handles peer/neighbor connection establishing. The \underline{playbook} so to speak.
+
+\begin{enumerate}
+    \item Idle: \gls{bgp} while initializing refuses all incoming connections. Will initiate \gls{tcp} connection to peer.
+    \item Connect: Waits for \gls{tcp} connection. If \gls{tcp} is established goes to state OpenSent. If \gls{tcp} is \textit{un}successful ConnectRetry timer is started and then goes to Active state.
     \item Active: When ConnectRetry counter reaches 0 goes to state Connect.
     \item OpenSent: Sends \gls{msg} to remote node. Waits for reply \gls{msg} before going to OpenConfirm.
     \item OpenConfirm: Nodes exchange keepalive \glspl{msg} and goes to Established state if successful.
     \item Established: Nodes can now exchange KeepAlive, Updates, and Notification \glspl{msg}.
-    \end{enumerate}
+\end{enumerate}
-\end{itemize}
 
+\subsection[iBGP]{Internal Border Gateway Protocol}
 
+\gls{ibgp} is running \gls{bgp} within the same \gls{as} between routers. Much like running a general \gls{igrp} in the network.
+
+Tradition one has to be fearful of creating \textit{routing loops} in the network. \glspl{bgp} mechanism for this is using either \begin{mylist} \item Full Mesh, or \item \glspl{rr} \end{mylist}.
+
+Problems by running \textit{Full Mesh} is the formula of \[ iBGPsessions = n*(n-1)/2 \] \note{where $ n $ is the number \gls{ibgp} speakers} which results in scaling problems as \gls{ibgp} speakers are added to the \gls{as}.
+
+\textit{\glspl{rr}} solves this problem by peering with all \gls{ibgp} speakers in the \gls{as}. All \gls{ibgp} speakers are then clients of the \glspl{rr}. This in turn helps maintainability by also advertising routes learnt from \gls{ibgp} clients to clients. Classic filtering/mathing route-maps/prefix-filters can be used to \textit{not} advertise all routes select group of clients from the \glspl{rr}.
+
+\subsection[eBGP]{External Border Gateway Protocol}
+
+\gls{ebgp} connections is inherently different from \gls{ibgp} connections. Some assumptions are made such as
+\begin{enumerate}
+    \item a \gls{ttl} of 1 is the default\footnote{Multi-hop \gls{ebgp} can thou be configured and therefore increase the max-\gls{ttl} value},
+    \item distance is set to 20 compared to 200 for \gls{ibgp} routes,
+    \item Next hop does \textit{not} change for \gls{ebgp} routes advertised to \gls{ibgp} neighbours \textit{by-default}\footnote{Often times it is necessary to tell a router to set itself as the next-hop before advertising to \gls{ibgp} neighbours}.
+\end{enumerate}

commands.tex

@@ -132,6 +132,11 @@ License: \texttt{\href{https://creativecommons.org/licenses/by-sa/3.0/}{CC BY-SA
 \newcommand{\rfc}[1]{RFC #1\footnote{\href{https://tools.ietf.org/html/rfc#1}{tools.ietf.org/html/rfc#1}}}
 
 
+% Usage: \note{<text>} or \nb{<text>}
+\newcommand{\note}[1]{{\color{Mahogany!20!black}{\small(#1)}}}
+\newcommand{\nb}[1]{\note{#1}}
+
+
 % Usage:
 % https://tex.stackexchange.com/a/75349
 \newcommand{\plaintextinput}[1]{\lstinputlisting[language={},style=plaintxt]{code/#1.txt}}

references-websites.bib

@@ -2,7 +2,7 @@
     author = "Hector Camba Lainez",
     title = "Cap4 implementing vtp",
     year = "2010",
-    url = {https://www.slideshare.net/lucky0679/cap4-implementing-vtp},
+    url = {\url{https://www.slideshare.net/lucky0679/cap4-implementing-vtp}},
     note = "[Online; accessed 22-May-2017]"
 }
 
@@ -31,3 +31,12 @@
     year = {2010},
     note = {(Accessed on 07/23/2017)}
 }
+
+@misc{ Differen15:online,
+    author = {\url{http://www.differencebetween.com/author/root/}{Andrew}},
+    title = "Difference Between EBGP and IBGP",
+    howpublished = {\url{http://www.differencebetween.com/difference-between-ebgp-and-vs-ibgp/}},
+    month = "September",
+    year = "2011",
+    note = "[Online; accessed on 24-June-2017]"
+}

structure.tex

@@ -191,7 +191,7 @@
 \geometry{a4paper,margin=1.5cm}
 \setlength{\columnsep}{1.5cm} %space between columns
 \setlength{\headheight}{15pt}
-\setlength{\footnotesep}{0.5cm} %space between footnotes:
+\setlength{\footnotesep}{1mm} %space between footnotes:
 \setlength{\skip\footins}{2cm} %space between the text body and the footnotes
 \setlist[itemize,1]{leftmargin=\dimexpr 26pt-.2cm}
 \setlist[itemize,2]{leftmargin=\dimexpr 26pt-.3cm}
@@ -273,3 +273,8 @@
 \renewcommand{\footnote}[1]{%
     \renewcommand\footnotesize\scriptsize % here there is scriptsize in footnotes (example)       
     \origfootnote{#1}}
+
+
+% https://tex.stackexchange.com/a/146312
+\newlist{mylist}{enumerate*}{1}
+\setlist[mylist]{label={\alph*)},font={\color{red!25!black}\bfseries}}