Potential networking questions:

What is a VLAN?
What’s the difference between VLAN and PVLAN?
What is STP?
What is the difference between Broadcast and Unicast flooding?
What is port security?
How many IP addresses are in a /26, /23, /18?
What’s the difference between routing and forwarding?
List some routing protocols and why you would use it over another.
What is BGP used for?
What is the difference between TCP and UDP and when would you use one over the other?
What is the Finite state machine?
What does a tracert do? What does a ping do?
What is a MTR?
What is IPAM?
Walk me through a layer 1 to 7 packet. Walk me through a layer 7 to 1.
What is a CAM table?
What does a broadcast domain really mean?
Why shouldn't I disable spanning tree? Or conversely, why should I disable it?
Also, does anyone care about RIPv1 anymore?
What if any difference is there between the operation of a layer 3 switch versus a router on a stick configuration?
You have RSTP enabled and you are seeing port flapping, what do you do?
Is it better practice in ACL's to use implicit deny all, or implicit allow all, and why?
Why should you / should you not enable portfast in a core switch.
You get a ticket and all it says is, "Help, the network is down!" What to do to resolve it?
BGP between two of your routers is down. Tell me what you would do to troubleshoot.
Can you explain what the 3-way handshake is?
What port does ping use?
What should the last line of a firewall rule set be?
How to configure a VPN, why it might fail at phase 1 or phase 2?
What is an IPsec?
What is the difference between RAID5 and RAID2?
How do DNS and DHCP relate?
What are some products AWS has and what do they do?
Windows PC has an IP address 169.254.X.X. What does it typically mean and whit the cause? How would you troubleshoot it? What would you look for on the DHCP server? Is there any log you can look at?
In class C space, how many host can you have in that space? Is there a special IP address that cannot be used?
What EXACTLY is TCP/IP?
    Tell me about different DNS record types.
    Is it possible to overwrite the DNS record at the PC?
How to find out if web server listens on the port?
* port DNS - 53
* port POP3 - 110
* port HTTP - 80
What is the UDP timeout value?
What is reverse DNS good for?
What are some HTTP errors and their meaning?
How many VPN tunnels can you have without NAT
What are the classes of private IPV6?
Interior/exterior gateway routing protocols difference?
"What exactly happens when you type www.amazon.com into the browser?"
What exactly is the cloud?
What is an IPsec tunnel and transport mode?
What’s the difference between main and aggressive mode?
Name some OSPF neighbor states.
TCP/IP window size and packet header?
What is the “grep” command?


“My personal favorite is taking out my wallet and my cell phone. I put them across the table from one another. Find a random piece of paper and place is in the middle.
This piece of paper, is a switch. He's already turned on.
These "nodes" are my computers. Off.
Tell me what happens when I turn one, or both, computers on.”