Syllabus, Calendar and such Textbook and lab notes: Lab 1 will be something to do with packet tracer Probably less scripted than Networking 1 And we'll talk more about the Cisco CLI on Monday for it I'm going to be maybe a week ahead of the class this time Really overrunning my knowledge Should keep me busy! I'm making Cyb300 up as I go too! And I'm also working on a couple research projects Note: Don't let all that stop you from asking me questions I'm here to help Chapters 1, 2, and 3: These are mostly review, but let's go over a few things anyway DNS: A good starting point Domain Name System What's it do? Let's catch a DNS request Wireshark GUI might be really small xrandr A few questions we can answer with wireshark: Does DNS use TCP or UDP? Is our system sending out DNS queries from the live stream? Does our system cache DNS queries? Do both web browsers send them out to the same server? Does dig actually use the DNS server we specified? Note: *nix systems and man Does dig generate a query if we specify a wrong server? If we run dig in an infinite loop, does it spam the DNS server? If we set up a fake DNS server with nc, can we reply to a request? Can wireshark catch a DNS request sent over the localhost interface? Can we change DNS servers? Should break things Hopefully not the live stream! Was it sending out DNS queries? What other commands does Linux have relating to DNS? apropos can answer that What if we wanted to run a DNS server? I used to use dnsmasq for that Generally we just send queries through somewhere else What DNS server does nikabrik use? How about isoptera? Exploring the lab: What's the IP address of the printer? What computers are online? What OS are they running? Where is the default gateway? What's the network ID? Broadcast address? Range of addresses? Default Gateway? How many addresses are available? What's the MTU?