100+ Network Support Engineer Interview Questions and Answers

IPv4 address is a unique numerical label assigned to each device connected to a computer network using Internet Protocol version 4.

• IPv4 address is a 32-bit address used to identify devices on a network.

• It is written in decimal format with four numbers separated by periods (e.g. 192.168.1.1).

• Each number in the address can range from 0 to 255.

• IPv4 addresses are used for communication and routing of data packets over a network.

Apache server is a web server software used to serve web pages and applications.

• Apache server is open-source software

• It is used to host websites and web applications

• It supports multiple programming languages like PHP, Python, and Perl

• It can be configured to handle SSL/TLS encryption for secure connections

• Apache server is highly customizable and extensible with modules

• Examples of websites using Apache server include Airbnb, Apple, and IBM

Switches connect devices within a network, while routers connect different networks and manage traffic between them.

• Switches operate at Layer 2 (Data Link) of the OSI model, while routers operate at Layer 3 (Network).

• Switches use MAC addresses to forward data, whereas routers use IP addresses.

• Example: A switch connects computers in a local office, while a router connects the office network to the internet.

• Switches create a local area network (LAN), while routers can connect m...read more

BGP is a routing protocol used in large-scale networks to exchange routing information between autonomous systems.

• BGP stands for Border Gateway Protocol.

• It is used to connect different autonomous systems (AS) on the internet.

• BGP allows routers in different ASs to exchange routing information and make informed decisions on the best paths for data transmission.

• It is a path-vector protocol that considers multiple factors like network policies, path attributes, and performance me...read more

Checking port configuration is crucial for network performance and security. It ensures proper connectivity and functionality.

• Verify VLAN assignment: Ensure the port is assigned to the correct VLAN for proper segmentation.

• Check speed and duplex settings: Confirm that the port speed (e.g., 100Mbps, 1Gbps) and duplex mode (full/half) match the connected device.

• Review port security settings: Ensure that MAC address filtering or port security features are configured to prevent un...read more

Configuring telnet and ssh, understanding OSI module and DHCP

• To configure telnet, enable the telnet service on the device and set a password for access

• To configure ssh, generate a public and private key pair and enable ssh service on the device

• OSI module is a conceptual model that describes how data is transmitted over a network

• DHCP is a protocol that automatically assigns IP addresses to devices on a network

Networking involves the communication between devices to share resources and information. TCP and UDP are protocols used for data transmission, VLANs separate networks, wireless networks use radio waves, and servers provide resources to clients.

• Networking is the practice of connecting devices to share resources and information

• TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) are protocols used for data transmission over networks

• VLANs (Virtual Local Area Net...read more

2G, 3G, and 5G are different generations of mobile network technology.

• 2G refers to second-generation mobile network technology, which primarily provided voice and basic data services.

• 3G refers to third-generation mobile network technology, which introduced faster data speeds and enabled mobile internet access.

• 5G refers to fifth-generation mobile network technology, which offers significantly faster data speeds, lower latency, and supports advanced technologies like Internet o...read more

The HTTPS port number is 443.

• HTTPS uses port 443 for secure communication.

• It is the default port for secure HTTP connections.

• HTTPS encrypts data using SSL/TLS protocols.

• Examples: https://www.example.com:443 or https://192.168.0.1:443

There are multiple ways to transfer data in CCNA, including wired and wireless methods.

• Data transfer methods in CCNA include Ethernet, Wi-Fi, Bluetooth, and cellular networks.

• Ethernet is a common wired method used for data transfer in CCNA.

• Wi-Fi allows for wireless data transfer over a local network.

• Bluetooth is used for short-range wireless data transfer between devices.

• Cellular networks enable data transfer over mobile networks.

There are two main types of modes in router configuration: user mode and privileged mode.

• User mode: Limited access to view router status and basic configurations.

• Privileged mode: Full access to configure, manage, and troubleshoot the router.

• Examples: 'show' command in user mode, 'configure terminal' command in privileged mode.

A port channel is a method used to bundle multiple physical ports together to increase bandwidth and redundancy. A firewall is a network security device that monitors and controls incoming and outgoing network traffic based on predetermined security rules.

• Port channel is used to increase bandwidth and redundancy by bundling multiple physical ports together

• Firewall is a network security device that monitors and controls network traffic based on security rules

• Port channel is co...read more

The OSI model is a conceptual framework used to understand network communication in seven layers.

• Layer 1: Physical - Deals with hardware connections (e.g., cables, switches).

• Layer 2: Data Link - Manages node-to-node data transfer (e.g., Ethernet).

• Layer 3: Network - Handles routing of data packets (e.g., IP addressing).

• Layer 4: Transport - Ensures complete data transfer (e.g., TCP, UDP).

• Layer 5: Session - Manages sessions between applications (e.g., API calls).

• Layer 6: Present...read more

STP stands for Spanning Tree Protocol.

• STP is a network protocol used to prevent loops in Ethernet networks.

• It works by creating a loop-free logical topology by blocking redundant paths.

• STP elects a root bridge and calculates the shortest path to it for each network segment.

• It uses Bridge Protocol Data Units (BPDU) to exchange information between switches.

• STP is defined by the IEEE 802.1D standard.

The OSI model has seven layers, each defining specific network functions and protocols for communication.

• 1. Physical Layer: Deals with the physical connection (e.g., cables, switches).

• 2. Data Link Layer: Manages node-to-node data transfer (e.g., Ethernet, PPP).

• 3. Network Layer: Handles routing and forwarding (e.g., IP, ICMP).

• 4. Transport Layer: Ensures reliable data transfer (e.g., TCP, UDP).

• 5. Session Layer: Manages sessions between applications (e.g., APIs).

• 6. Presentation ...read more

A firewall is a network security system that monitors and controls incoming and outgoing network traffic.

• Firewalls can be hardware or software-based.

• They use a set of rules to determine whether to allow or block traffic.

• Firewalls can be configured to block specific types of traffic, such as certain websites or protocols.

• They can also be configured to allow traffic from specific IP addresses or domains.

• Firewalls can help prevent unauthorized access to a network and protect aga...read more

Routing is the process of selecting the best path for network traffic to reach its destination.

• Routing helps in efficient and effective communication between devices on a network.

• It involves analyzing network topology and selecting the best path based on factors like distance, speed, and cost.

• Routing protocols like OSPF, BGP, and EIGRP are used to automate the process of routing.

• Routing is essential for the internet to function, as it enables communication between different n...read more

VLAN is a virtual LAN that allows network devices to communicate as if they were on the same physical network. ABR router is a router that connects two or more areas in a network.

• VLAN separates a physical network into multiple logical networks

• Devices in different VLANs cannot communicate without a router

• ABR router connects different areas in a network, such as OSPF areas or IS-IS levels

• ABR router maintains separate routing tables for each area it connects

The number of VLANs that can be configured in an L2 switch depends on the specific model and manufacturer, but typically ranges from 4 to 4096.

• The number of VLANs supported by an L2 switch is determined by the switch's hardware capabilities and software limitations.

• Most L2 switches support a minimum of 4 VLANs and a maximum of 4096 VLANs.

• Higher-end switches may support even more VLANs, while lower-end switches may have a lower limit.

• Some switches may have restrictions on the ...read more

DHCP is a network protocol that assigns IP addresses to devices. DNS translates domain names to IP addresses. IP address is a unique identifier for devices. CDN is a content delivery network.

• DHCP - Dynamic Host Configuration Protocol assigns IP addresses to devices on a network

• DNS - Domain Name System translates domain names to IP addresses

• IP address - Internet Protocol address is a unique identifier for devices on a network

• CDN - Content Delivery Network is a distributed netw...read more

Routing directs data packets between networks, ensuring efficient data transfer across interconnected devices.

• Routing involves determining the best path for data to travel across networks.

• Routers use routing tables to make decisions about where to forward packets.

• Static routing is manually configured, while dynamic routing uses protocols like OSPF or BGP.

• Example: A router may use OSPF to find the shortest path to a destination IP address.

• Routing can be influenced by metrics s...read more

Public IP is the address assigned to a device on the internet, while private IP is the address assigned to a device on a local network.

• Public IP is unique and globally routable, allowing devices to communicate over the internet.

• Private IP is used within a local network and is not accessible from the internet.

• Public IP is assigned by the Internet Service Provider (ISP), while private IP is assigned by the local network's router.

• Public IP can be static or dynamic, while private...read more

The packet flow of the dr and bdr election is the process by which routers in a network determine the designated router and backup designated router.

• DR and BDR are elected in OSPF networks to reduce the amount of OSPF traffic and maintain network stability.

• The election process begins with routers exchanging Hello packets to establish neighbor relationships.

• Routers with higher OSPF priority or higher router ID are preferred for the DR and BDR roles.

• The DR and BDR multicast OSP...read more

My biggest strength is problem-solving skills, while my weakness is sometimes over-analyzing issues.

• Strength: Strong analytical skills - I can quickly diagnose network issues, as demonstrated when I resolved a major outage in under an hour.

• Strength: Excellent communication - I effectively convey technical information to non-technical staff, ensuring everyone is on the same page.

• Weakness: Over-analyzing - I tend to spend too much time on details, which can delay decision-makin...read more

Company roles define responsibilities, ensuring efficient operations and collaboration among teams to achieve organizational goals.

• Network Support Engineers troubleshoot network issues, ensuring minimal downtime.

• They collaborate with IT teams to implement network upgrades and enhancements.

• Documentation of network configurations and changes is crucial for future reference.

• Providing training and support to end-users on network-related issues is part of their role.

Router configurations involve setting up and managing network devices to ensure efficient and secure communication.

• Router configurations involve configuring IP addresses, subnet masks, and default gateways.

• Setting up access control lists (ACLs) to control network traffic.

• Enabling routing protocols such as OSPF or BGP for dynamic routing.

• Configuring NAT (Network Address Translation) to allow private IP addresses to access the internet.

• Implementing security measures like firewa...read more

A network is a collection of computers, servers, mainframes, network devices, and other devices connected to one another for sharing data and resources.

• Networks can be wired or wireless

• Networks can be local (LAN), wide area (WAN), or global (Internet)

• Networks use protocols like TCP/IP for communication