Networking Concepts
What is the purpose of the OSI model in networking?
It provides a framework for understanding and designing network communications.
What is the primary purpose of a VLAN?
To segment a network into separate broadcast domains.
What is the purpose of a network baseline?
To document normal network performance for comparison during troubleshooting
What does a firewall do in a network?
It filters traffic based on predefined rules to enhance security.
What is the first step in the troubleshooting process?
Identify the problem.
At which layer of the OSI model do routers primarily operate?
Layer 3 (Network Layer)
What type of cable is used for connecting similar devices, such as two switches?
A crossover cable (though auto-MDI/MDIX has largely replaced this need).
Which type of backup strategy captures only changes made since the last full backup?
Incremental backup.
What is the difference between symmetric and asymmetric encryption?
Symmetric uses the same key for encryption and decryption; asymmetric uses a public and private key pair.
Which tool would you use to trace the path packets take across a network?
tracert
What protocol is used to automatically assign IP addresses to devices on a network?
DHCP
What is a trunk port used for on a switch?
It carries traffic for multiple VLANs between switches.
What tool is commonly used to monitor network performance in real-time?
Network monitoring tools like SolarWinds or PRTG or Wireshark
What is the purpose of a DMZ in network security?
To isolate external-facing services from the internal network.
What does the ping command test?
Connectivity and reachability between devices.
What does CIDR stand for, and why is it used?
Classless Inter-Domain Routing, used for more efficient IP address allocation.
Which type of wireless network topology allows devices to communicate directly without a central access point?
Ad-hoc mode
What is the term for a document outlining procedures and responsibilities during a network incident?
IRP (Incident Response Plan)
What is a man-in-the-middle attack?
An attack where an attacker intercepts and potentially alters communication between two parties.
What is the purpose of loopback testing?
To test the functionality of a network interface card (NIC).
What is the primary difference between TCP and UDP in terms of reliability?
TCP provides reliable, connection-oriented communication, while UDP is connectionless and does not guarantee delivery.
What does PoE stand for, and what does it enable?
Power over Ethernet, enabling devices like cameras and access points to receive power and data over a single cable
What does the MTTR metric measure in network operations?
Mean Time to Repair—how long it takes to resolve a failure.
What is the difference between a stateful and stateless firewall?
A stateful firewall tracks the state of active connections, while a stateless firewall filters packets based on static rules.
How would you diagnose a DNS resolution issue?
Use commands like nslookup, dig, or check the DNS server configuration.