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+= Network analysis !
+Apostolos rootApostolos@swarmlab.io
+// Metadata:
+:description: Intro and Install
+:keywords: sec, tcpdump
+:data-uri:
+:toc: right
+:toc-title: Πίνακας περιεχομένων
+:toclevels: 4
+:source-highlighter: highlight
+:icons: font
+:sectnums: 
+
+include::header.adoc[]
+
+
+{empty} +
+
+
+[[cheat-Docker]]
+== Install swarmlab-sec (Home PC)
+
+HowTo: See http://docs.swarmlab.io/lab/sec/sec.adoc.html
+
+
+.NOTE
+[NOTE]
+====
+Assuming you're already logged in
+====
+
+
+**tcpdump** is a common packet analyzer that runs under the command line. It allows the user to display TCP/IP and other packets being transmitted or received over a network to which the computer is attached. Distributed under the BSD license, tcpdump is free software. 
+
+https://en.wikipedia.org/wiki/Tcpdump[More: wikipedia]
+
+== Basic
+
+=== Everything on an interface
+
+Just see what’s going on, by looking at what’s hitting your interface.
+
+[source,bash]
+----
+tcpdump -i eth0
+----
+
+=== Find Traffic by IP
+
+One of the most common queries, using host, you can see traffic that’s going to or from 1.1.1.1.
+
+[source,bash]
+----
+tcpdump host 1.1.1.1
+----
+
+
+=== Filtering by Source and/or Destination
+
+If you only want to see traffic in one direction or the other, you can use src and dst.
+
+[source,bash]
+----
+tcpdump src 1.1.1.1
+tcpdump dst 1.0.0.1
+----
+
+=== Finding Packets by Network
+
+To find packets going to or from a particular network or subnet, use the net option.
+
+[source,bash]
+----
+tcpdump net 1.2.3.0/24
+----
+
+
+=== Show Traffic Related to a Specific Port
+
+You can find specific port traffic by using the port option followed by the port number.
+
+[source,bash]
+----
+tcpdump port 3389
+tcpdump src port 1025
+----
+
+=== Show Traffic of One Protocol
+
+If you’re looking for one particular kind of traffic, you can use tcp, udp, icmp, and many others as well.
+
+[source,bash]
+----
+tcpdump icmp
+----
+
+=== Reading / Writing Captures to a File (pcap)
+
+It’s often useful to save packet captures into a file for analysis in the future. These files are known as PCAP (PEE-cap) files, and they can be processed by hundreds of different applications, including network analyzers, intrusion detection systems, and of course by tcpdump itself. Here we’re writing to a file called capture_file using the -w switch.
+
+
+[source,bash]
+----
+tcpdump port 80 -w capture_file
+----
+
+
+== Advanced
+
+
+
+
+
+
+
+
+
+
+
+
+[appendix]
+== How to use tcpdump
+
+
+This exercise will show you how to isolate traffic in various ways—from IP, to port, to protocol, to application-layer traffic—to make sure you find exactly what you need as quickly as possible.
+
+
+
+
+
+
+
+:hardbreaks:
+
+{empty} +
+{empty} +
+{empty} 
+
+:!hardbreaks:
+
+'''
+
+.Reminder
+[NOTE]
+====
+:hardbreaks:
+Caminante, no hay camino, 
+se hace camino al andar.
+
+Wanderer, there is no path, 
+the path is made by walking.
+
+*Antonio Machado* Campos de Castilla
+====