What are the two types of network addresses assigned to a device?
MAC Address (Physical/Permanent) and IP Address (Logical/Changeable).
What happens to a laptop’s addresses when it moves to a different network?
The MAC address stays the same, but the IPv4/IPv6 addresses change.
What command is used in Windows to display the MAC address?
ipconfig /all
What are the two parts of an IPv4 address?
The Network portion and the Host portion.
What determines which part of an IPv4 address is the network part?
The Subnet Mask.
What are the two main rules for compressing an IPv6 address?
- Omit leading zeros. 2. Omit all-zero segments using a double colon (::) only once.
What four pieces of information are required for a static IP configuration?
- IP Address, 2. Subnet Mask, 3. Default Gateway, 4. DNS Server.
What is a Default Gateway?
The IP address of the router that allows a device to communicate with other networks or the internet.
What is APIPA (Automatic Private IP Addressing)?
A link-local IPv4 address (169.254.x.x) a device assigns itself if it cannot obtain an address from a DHCP server.
What protocol does the ping command use?
ICMP (Internet Control Message Protocol).
What is the first security step a technician should take when configuring a new wireless router?
Change the default username and password immediately.
How do you renew a DHCP IP address via the command line?
Run ipconfig /release followed by ipconfig /renew.
What is NAT (Network Address Translation)?
A process that converts private IPv4 addresses to a single, internet-routable public IP address.
What is QoS (Quality of Service)?
A configuration that prioritizes specific traffic (like voice or video) over less time-sensitive data (like email).
Why is UPnP (Universal Plug and Play) considered a security risk?
It allows devices to dynamically add themselves to a network and open firewall ports without user intervention.
What is a DMZ (Demilitarized Zone)?
A sub-network that exposes specific services (like web servers) to an untrusted network (the internet) while protecting the internal LAN.
Contrast Port Forwarding vs. Port Triggering.
Forwarding: Permanent rule to send data to a specific device/port. Triggering: Temporary opening of ports based on an outbound request.
What is MAC Address Filtering?
A security feature that specifies exactly which hardware addresses are allowed to connect to the wireless network.
Contrast Whitelisting vs. Blacklisting in a firewall.
Whitelisting: Blocks everything except specific allowed sites. Blacklisting: Allows everything except specific blocked sites.
What is the Internet of Things (IoT)?
A network of physical objects (smart appliances, sensors) that connect to the internet to collect and exchange data.
Step 1 (Troubleshoot): What is an example of an open-ended question for a network issue?
“What happens when you try to access the internet?”
Step 2 (Troubleshoot): What are three “Probable Causes” for a device having no network connectivity?
- Loose cables, 2. Power off on the router, 3. Wrong IP settings (NIC disabled).
Step 5 (Troubleshoot): What must a technician do after implementing a solution?
Verify full functionality and implement preventive measures (e.g., reboot all devices to ensure connectivity persists).
Symptom: A user has a 169.254.x.x IP address. What is the problem?
The computer cannot communicate with the DHCP server.
