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Cyberssec progress 9.6.26

======Review so far:  =================================
We learned about physical links: 
  • ethernet cables
  • 8 wires in pairs
  • on pair is transmit (TX) one is receive (RX)
  • full duplex (talking and listening at the same time)
We used terminal to learn about our computer, and to reach out to other computers:
  • whoami, last, history, top
  • ssh (secure shell), ping, traceroute
  • nslookup, dig (names to numbers)
  • commands and flags (shutdown -r now)
  • privileges: root and sudo
  • ctrl-c and ctrl-x (stop and halt)
We learned how to scan a network:
  • IP net monitor
  • arp-scan
  • nmap
We learned about network architecture:
  •  subnets
  • IP addresses
  • 192.168.1.x and 10.14.x.y networks
  • gateways
  • domain name service (DNS)
We need to learn to navigate around the guts of another computer, locally or remotely: why?
  • pwd tells you where you are (print working directory) like on a elevator, which floor you are on
  • ls tells me what is on that "floor"
  • ls -la tells me about even the hidden things on the floor
  • ls -lha does all of this in human form
  • cd means change directory (floor) on the elevator
Try this:
sudo nano <name> is how we create a file
  • in terminal, navigate to your desktop folder
  • create a new document called secret: sudo nano secret
  • type some secret stuff there
  • type ctrl-o (overwrite) and ctrl-x (exit)
  • look around your folders for the secret file
  • Ok, now repeat the process, creating a file called .hidden (the period makes it hidden)
  • type stuff and save
  • now look for the file
  • ask your friends to find your files by ssh into your machine (don't tell them what you wrote)

to create a new folder (directory) we use mkdir (make a directory)
  • try mkdir mystuff (no spaces, computers freak out with spaces)
  • cd into that folder: cd mystuff
  • make a document there
  • ask your friends to find it
  • look on your desktop for the folder
  • create a hidden file there, see if they can find it
I have hidden a file in another computer, with a reference to yet another computer.
Your challenge is to find the files.