60+ Network Engineer Interview Questions and Answers for Freshers

The question covers various networking concepts and protocols such as STP, EIGRP, OSPF, TCP header, and IOS commands.

• STP (Spanning Tree Protocol) is used to prevent loops in a network.

• EIGRP (Enhanced Interior Gateway Routing Protocol) dual algorithm is a routing protocol used in Cisco networks.

• Static Routing is a type of routing where the network administrator manually configures the routes.

• Administrative Value is a numerical value assigned to different routing protocols to d...read more

The subnet mask for CIDR /29 is 255.255.255.248.

• CIDR /29 means 29 bits are used for the network portion and 3 bits for the host portion.

• To calculate the subnet mask, convert the 29 network bits to 1s and add 3 0s for the host bits.

• The result is 255.255.255.248 in dotted decimal notation.

A router is a networking device that forwards data packets between computer networks.

• Routers operate at the network layer of the OSI model.

• They use routing tables to determine the best path for data packets to travel.

• Routers can connect different types of networks, such as LANs and WANs.

• Examples of routers include Cisco, Juniper, and TP-Link.

• Routers can provide security features such as firewalls and VPNs.

DNS stands for Domain Name System. It is a system that translates domain names into IP addresses.

• DNS is used to resolve domain names to IP addresses

• It works by querying DNS servers to find the IP address associated with a domain name

• To secure a website, one can use SSL/TLS certificates to encrypt data transmitted between the website and the user

• Other security measures include implementing firewalls, using strong passwords, and keeping software up to date

PPPoE is a protocol used to connect devices to the internet through a DSL line. WAN stands for Wide Area Network. Routers are configured to connect devices to the internet.

• PPPoE stands for Point-to-Point Protocol over Ethernet

• It is used to establish a connection between a device and an ISP through a DSL line

• WAN is a network that covers a large geographical area, such as the internet

• Routers are configured with settings such as IP address, subnet mask, default gateway, and DNS ...read more

Firewalls are used to protect networks from unauthorized access and have features like packet filtering, NAT, VPN, and IDS/IPS.

• Firewalls prevent unauthorized access to a network by filtering incoming and outgoing traffic based on predefined rules.

• They can also perform Network Address Translation (NAT) to hide the internal IP addresses from external networks.

• Firewalls can establish Virtual Private Networks (VPNs) to securely connect remote users or sites to the network.

• They ca...read more

Yes, I have knowledge of Windows OS configuration.

• I am familiar with configuring network settings, such as IP addresses and DNS servers.

• I know how to manage user accounts and permissions.

• I am experienced in installing and updating software and drivers.

• I am proficient in troubleshooting common issues, such as blue screens and slow performance.

• I am knowledgeable in configuring security settings, such as firewalls and antivirus software.

To create firewall rules on a Checkpoint device, follow these steps:

• Log in to the Checkpoint device using SmartConsole

• Navigate to the Firewall tab and select the Access Rules section

• Click on the Add Rule button and specify the source, destination, and service for the rule

• Set the action for the rule (allow, drop, reject, etc.)

• Click on Install Policy to apply the new rule to the device

STP stands for Spanning Tree Protocol. It is used to prevent loops in a network and ensure redundancy.

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

• It ensures that there is only one active path between any two network devices.

• STP works by creating a tree-like structure of the network, with one root bridge and multiple branches.

• If a link fails, STP will automatically reroute traffic to an alternate path.

• Examples of STP variants include RSTP, MSTP, an...read more

VLANs are used to logically separate network traffic and improve network performance and security.

• VLANs allow for better network management and organization by grouping devices based on their function or location.

• They also reduce network congestion by limiting broadcast traffic to devices within the same VLAN.

• VLANs can improve network security by isolating sensitive data or devices from the rest of the network.

• For example, a finance department may have their own VLAN to keep ...read more

Yes, I have plans to pursue CCNA certification in the near future.

• I have already started studying for the CCNA exam

• I believe that obtaining the CCNA certification will enhance my skills and knowledge in network engineering

• I plan to take the exam within the next 6 months

I operate various network monitoring and troubleshooting tools.

• I am proficient in using Wireshark for packet analysis

• I have experience with Cisco Prime Infrastructure for network management

• I am familiar with SolarWinds for network monitoring

• I have used PingPlotter for network troubleshooting

• I am comfortable with CLI tools like ping, traceroute, and netstat

BGP can be implemented in a Cisco Router by configuring the router as a BGP router and establishing BGP peering with other routers.

• Configure the router as a BGP router using the 'router bgp' command.

• Specify the AS number using the 'bgp autonomous-system' command.

• Configure BGP neighbors using the 'neighbor' command.

• Configure BGP attributes such as network statements, route maps, and access lists.

• Verify BGP peering using the 'show ip bgp summary' command.

HSRP is a protocol used to provide redundancy for IP networks. It allows two or more routers to share a virtual IP address.

• Configure HSRP on two or more routers with the same group number and virtual IP address

• One router is elected as the active router and forwards packets sent to the virtual IP address

• The other router(s) are in standby mode and take over if the active router fails

• HSRP can be used to provide default gateway redundancy for hosts on a LAN

• HSRP can also be used f...read more

Network is a collection of interconnected devices that communicate with each other using protocols.

• DHCP (Dynamic Host Configuration Protocol) is a network protocol that automatically assigns IP addresses to devices on a network.

• A switch is a networking device that connects devices on a local area network (LAN) and forwards data packets between them.

• A router is a networking device that connects multiple networks and forwards data packets between them.

• IP (Internet Protocol) is ...read more

A diode is an electronic component that allows current to flow in only one direction.

• It has two terminals, an anode and a cathode.

• It is commonly used in rectifiers to convert AC to DC.

• It can also be used as a voltage regulator or a signal modulator.

• Examples include the 1N4148 and the 1N4001 diodes.

Ether channel protocol is a technology used in networking to combine multiple physical links into a single logical link for increased bandwidth and redundancy.

• Ether channel protocol is also known as link aggregation or port trunking.

• It allows multiple physical links to be bundled together to form a single logical link.

• This increases the overall bandwidth and provides redundancy in case of link failures.

• Ether channel protocol is commonly used in data centers and enterprise net...read more

Ethernet channel and BGP are used to pass traffic. Traffic can be passed by configuring the Ethernet channel and BGP protocol.

• Ethernet channel is a link aggregation technology that allows multiple physical links to be combined into a single logical link.

• BGP (Border Gateway Protocol) is a routing protocol used to exchange routing information between different networks.

• To pass traffic in Ethernet channel, the channel needs to be configured on both ends of the link and the devic...read more

Telecom refers to communication over a distance using technology, while network refers to interconnected devices sharing resources and information.

• Telecom involves transmitting data over long distances using various technologies like telephone lines, satellites, and fiber optics.

• Network refers to a group of interconnected devices that can communicate and share resources, such as computers, servers, and printers.

• Telecom is essential for establishing communication links between...read more

Routers are used to connect different networks together and route traffic between them.

• Routers provide network segmentation and security by separating broadcast domains.

• They can also prioritize traffic and optimize network performance.

• Examples of routers include Cisco, Juniper, and MikroTik.

• Routers are essential for connecting to the internet and accessing remote networks.

DSCP (Differentiated Services Code Point) is a network protocol used to prioritize and manage network traffic based on its importance.

• DSCP is a field in the IP header that assigns a value to packets to indicate their priority

• It allows network administrators to control and prioritize traffic flow

• DSCP values range from 0 to 63, with higher values indicating higher priority

• Different applications or services can be assigned different DSCP values to ensure quality of service

• For ex...read more

L2 switches operate at the data link layer and L3 switches operate at the network layer of the OSI model.

• L2 switches forward traffic based on MAC addresses while L3 switches forward traffic based on IP addresses.

• L2 switches are used for LANs while L3 switches are used for both LANs and WANs.

• L2 switches are simpler and less expensive than L3 switches.

• L3 switches can perform routing functions while L2 switches cannot.

• Examples of L2 switches include Cisco Catalyst 2960 and HP Pr...read more

SDWAN connectivity through Cisco router involves configuring the router to support SDWAN technology.

• Configure the router to support SDWAN technology

• Ensure the router has the necessary hardware and software capabilities

• Configure the SDWAN policies and rules on the router

• Test and verify the connectivity and performance of the SDWAN network

CNC codes are instructions used in computer numerical control (CNC) machines to control their movements and operations.

• CNC codes include G-codes, M-codes, and other codes specific to the machine or software being used.

• G-codes control the movement of the machine, such as positioning, cutting speed, and tool changes.

• M-codes control auxiliary functions like coolant, spindle rotation, and tool changes.

• Other codes may be used for specific operations or features, such as tool compe...read more

VLAN stands for Virtual Local Area Network. It is a logical grouping of devices on a network based on function, department or application.

• VLANs allow for better network management and security by separating traffic into different broadcast domains.

• Devices in different VLANs cannot communicate with each other without a router or layer 3 switch.

• VLANs can be configured based on port, MAC address or protocol.

• Example: VLAN 10 for finance department, VLAN 20 for marketing departmen...read more

TCP/IP is a protocol suite used for communication between devices on the internet.

• TCP/IP has four layers: application, transport, internet, and network access.

• The application layer includes protocols like HTTP, FTP, and SMTP.

• The transport layer includes TCP and UDP protocols.

• The internet layer is responsible for routing packets between networks.

• The network access layer includes protocols like Ethernet and Wi-Fi.

• TCP/IP is the foundation of the internet and is used for communic...read more

A network is a group of interconnected devices that communicate with each other. LAN is a type of network that covers a small area.

• Network is a collection of devices that are connected to each other to share resources and information.

• LAN stands for Local Area Network and is a type of network that covers a small geographical area such as a home, office, or building.

• LAN is usually owned and managed by a single organization and provides high-speed connectivity between devices.

• Ex...read more

STP loop prevention is achieved by blocking redundant paths in a network to prevent loops.

• STP (Spanning Tree Protocol) identifies redundant paths in a network

• STP selects a root bridge to be the central point of the network

• STP blocks certain ports to prevent loops while still allowing for redundancy

• If a link fails, STP will unblock a previously blocked port to maintain connectivity

IPSECVPN, OSPF, EIGRP, and L2TP are all networking protocols used for secure communication and routing.

• IPSECVPN is a protocol used for secure communication over the internet.

• OSPF and EIGRP are routing protocols used for efficient data transfer between network devices.

• L2TP is a protocol used for creating virtual private networks (VPNs) over the internet.

• All of these protocols are important for secure and efficient networking in modern IT environments.

Telecom refers to communication over a distance using various technologies, while a network is a collection of interconnected devices that can communicate with each other.

• Telecom involves transmitting data over long distances using technologies like telephone lines, fiber optics, and satellites

• Network refers to a collection of devices like computers, servers, and routers that are connected to each other to share resources and communicate

• Telecom networks enable communication b...read more

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

• It acts as a barrier between a trusted internal network and an untrusted external network

• It can be hardware, software, or a combination of both

• It can be configured to block or allow traffic based on predefined rules

• Examples include Cisco ASA, Fortinet FortiGate, and Palo Alto Networks firewall

The formula for power is the rate at which work is done or energy is transferred.

• Power = Work / Time

• Power = Force x Velocity

• Power = Voltage x Current

• Power = (Current)^2 x Resistance

OSPF (Open Shortest Path First) is a routing protocol used to determine the best path for data to travel in a network.

• OSPF is a link-state protocol that uses Dijkstra's algorithm to calculate the shortest path between two points.

• It is used in large enterprise networks and is designed to scale well.

• OSPF routers exchange information about their connected networks and use this information to build a topology map of the network.

• This topology map is used to determine the best path...read more

Configuring a router involves accessing its web interface, setting up basic network settings, and configuring advanced features.

• Connect to the router's web interface using a web browser

• Set up basic network settings such as IP address, subnet mask, and default gateway

• Configure advanced features such as port forwarding, DHCP, and firewall rules

• Save and apply the changes to the router's configuration

• Test the router's connectivity and functionality

Static and DHCP are two methods of assigning IP addresses to devices on a network.

• Static IP addresses are manually assigned to a device and do not change unless manually reconfigured.

• DHCP (Dynamic Host Configuration Protocol) automatically assigns IP addresses to devices on a network.

• DHCP can also assign other network configuration information, such as subnet mask and default gateway.

• Static IP addresses are useful for devices that require a consistent IP address, such as serv...read more

VPN stands for Virtual Private Network. It is a secure and encrypted connection between two networks or devices over the internet.

• VPN allows remote access to a private network over the internet

• It provides security and privacy by encrypting the data transmitted

• VPN can be used to bypass geo-restrictions and access content not available in your region

• Examples of VPNs include OpenVPN, Cisco AnyConnect, and NordVPN

RFS ready for service refers to the status of a network element or service that is ready to be used by end-users.

• RFS is a term commonly used in telecommunications and networking industries

• It indicates that a network element or service has been tested and is ready for use by end-users

• RFS is often used in the context of new installations or upgrades

• For example, when a new cell tower is installed, it is not considered RFS until it has been tested and is ready to provide service ...read more

BGP stands for Border Gateway Protocol. It is a routing protocol used to exchange routing information between different networks.

• BGP is used in large-scale networks such as the internet.

• It is a path-vector protocol that selects the best path for data to travel between networks.

• BGP uses TCP port 179 for communication.

• It is used to connect different autonomous systems (AS) together.

• BGP is used to prevent routing loops and ensure efficient routing.

• An example of BGP in action is ...read more

BGP stands for Border Gateway Protocol. It is a routing protocol used to exchange routing information between different networks.

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

• It is a path-vector protocol that selects the best path for data to travel based on policies set by network administrators.

• BGP uses TCP port 179 for communication between routers.

• BGP is used by internet service providers (ISPs) to connect to each other and exchange routing info...read more

VLANs provide segmentation, security, and flexibility in network design.

• VLANs allow for logical segmentation of a network, separating traffic into different broadcast domains.

• This improves network performance and reduces congestion.

• VLANs also provide enhanced security by isolating sensitive data and restricting access to certain areas of the network.

• They also allow for flexibility in network design, making it easier to add, move, or change devices without disrupting the entir...read more

Yes, I have completed network training.

• I have completed courses in CCNA, CCNP, and CompTIA Network+.

• I have also attended workshops on network security and troubleshooting.

• I keep myself updated with the latest technologies and industry trends.

CNC stands for Computer Numerical Control. It is a manufacturing process that uses computerized systems to control machine tools.

• CNC is used in various industries such as automotive, aerospace, and electronics.

• It involves the use of computer programs to control the movement and operation of machine tools.

• CNC machines can perform precise and complex tasks, such as cutting, drilling, and shaping materials.

• Examples of CNC machines include CNC mills, lathes, routers, and plasma c...read more

Server LAN is a local area network that connects servers within an organization.

• Server LAN is used to connect servers within an organization

• It allows for efficient communication and data sharing between servers

• It is typically faster and more secure than a wide area network (WAN)

• Examples of server LANs include Microsoft Windows Server, Linux Server, and Apple macOS Server

The OSI model is a conceptual framework that standardizes the functions of a telecommunication or computing system into seven layers.

• The OSI model stands for Open Systems Interconnection model.

• It consists of seven layers: Physical, Data Link, Network, Transport, Session, Presentation, and Application.

• Each layer has specific functions and communicates with the adjacent layers.

• The model helps in understanding how data is transmitted over a network.

• For example, the Physical laye...read more

Ohm's Law states that the current flowing through a conductor is directly proportional to the voltage applied across it, and inversely proportional to the resistance of the conductor.

• Ohm's Law is represented by the formula V = I * R, where V is voltage, I is current, and R is resistance.

• It helps in calculating the relationship between voltage, current, and resistance in an electrical circuit.

• For example, if a circuit has a voltage of 12 volts and a resistance of 4 ohms, the c...read more

Active Directory can be created by installing the Active Directory Domain Services role on a Windows Server.

• Install the Active Directory Domain Services role on a Windows Server

• Run the Active Directory Domain Services Configuration Wizard

• Create a new forest or domain

• Set up the domain controller

• Configure the domain settings

Yes, I have completed the CCNA certification.

• I have a strong understanding of networking concepts and protocols.

• I am proficient in configuring and troubleshooting Cisco routers and switches.

• I have experience in designing and implementing network solutions.

• I am familiar with network security and have knowledge of VPNs and firewalls.