100+ NOC Engineer Interview Questions and Answers

To access others' computers on our PC within a single network, we can use remote desktop tools like Remote Desktop Protocol (RDP) or Virtual Network Computing (VNC).

• Remote Desktop Protocol (RDP) allows accessing Windows-based computers remotely.

• Virtual Network Computing (VNC) enables remote access to computers running various operating systems.

• Both RDP and VNC require the target computer to have the necessary software and permissions set up.

• Other tools like TeamViewer, AnyDes...read more

The latest router and switch used in the market are Cisco Catalyst 9000 Series switches and Cisco ASR 9000 Series routers.

• Cisco Catalyst 9000 Series switches are known for their advanced security features and programmability.

• They offer high performance and scalability for enterprise networks.

• Cisco ASR 9000 Series routers provide high-density, high-performance routing and are suitable for service provider networks.

• They support advanced features like segment routing and network...read more

GSM architecture includes multiple layers of OSI model for connectivity. Each layer has a specific function.

• GSM architecture consists of physical, data link, network, transport, and application layers.

• Physical layer handles the transmission of bits over the air interface.

• Data link layer provides error-free transmission of data frames.

• Network layer handles routing and addressing of data packets.

• Transport layer ensures reliable end-to-end data transfer.

• Application layer provide...read more

The difference between color coding of 568A and 568B is the arrangement of the wire pairs in the Ethernet cable.

• 568A uses a different order for the green and orange wire pairs compared to 568B.

• 568A: white-green, green, white-orange, blue, white-blue, orange, white-brown, brown

• 568B: white-orange, orange, white-green, blue, white-blue, green, white-brown, brown

• Both standards are used for Ethernet connections, but 568B is more commonly used in the United States.

• The color coding ...read more

Configuring routers and switches involves setting up network protocols, IP addresses, VLANs, and security features.

• Access the router/switch CLI through console or SSH.

• Configure basic settings like hostname, domain name, and passwords.

• Set up IP addresses and subnet masks on interfaces.

• Enable routing protocols like OSPF or BGP for routers.

• Create VLANs and assign ports to them on switches.

• Implement security features like access control lists (ACLs) or port security.

• Test connecti...read more

A series of technical questions related to networking and protocols.

• ARP is a protocol used to map an IP address to a physical address

• Telnet uses port 23 and SSH uses port 22 for remote access to network devices

• STP (Spanning Tree Protocol) prevents loops in a network by blocking redundant paths

• VTP (VLAN Trunking Protocol) allows for the propagation of VLAN information across a network

• VLANs (Virtual Local Area Networks) allow for logical segmentation of a network

• DHCP (Dynamic H...read more

The tool or command to resume copying data from where it left off in a Linux server is rsync.

• Use rsync command with the --partial and --progress options to resume copying data from where it left off.

• Example: rsync --partial --progress source_directory/ destination_directory/

Straight cables are used to connect different types of devices, while cross cables are used to connect similar devices.

• Straight cables are used to connect a computer to a switch, router, or hub.

• Cross cables are used to connect two computers directly or to connect two switches or hubs together.

• Straight cables have the same wiring sequence on both ends, while cross cables have a different wiring sequence on each end.

• Straight cables use the T568A or T568B wiring standard, while ...read more

Internet is a global network of interconnected computers and servers that communicate with each other using standardized protocols.

• Internet is a network of networks that allows communication and sharing of information across the globe.

• It was developed in the late 1960s and early 1970s by the United States Department of Defense.

• The World Wide Web, email, and instant messaging are some of the popular applications of the internet.

• The internet has revolutionized the way we commun...read more

Topology refers to the arrangement of nodes and connections in a network. Types include bus, star, ring, mesh, and hybrid.

• Topology defines the physical or logical layout of a network.

• Bus topology connects all devices to a single cable.

• Star topology connects devices to a central hub or switch.

• Ring topology connects devices in a circular loop.

• Mesh topology connects devices with multiple redundant paths.

• Hybrid topology combines two or more types of topologies.

• Examples: Ethernet ...read more

DHCP stands for Dynamic Host Configuration Protocol. It is a network protocol that enables devices to obtain IP addresses automatically.

• DHCP is used to assign IP addresses to devices on a network.

• The DHCP process involves four steps: discovery, offer, request, and acknowledgement.

• During the discovery phase, a device sends a broadcast message to find a DHCP server.

• The DHCP server responds with an offer, providing an available IP address.

• The device then sends a request to the D...read more

OSI model is a conceptual model that characterizes and standardizes the communication functions of a telecommunication or computing system.

• OSPF (Open Shortest Path First) is a routing protocol used for Internet Protocol (IP) networks.

• DNS (Domain Name System) is a hierarchical and decentralized naming system for computers, services, or other resources connected to the Internet.

• DHCP (Dynamic Host Configuration Protocol) is a network management protocol used to dynamically assig...read more

To troubleshoot no internet connection, check physical connections, restart devices, verify settings, and contact ISP.

• Check physical connections (cables, modem, router)

• Restart devices (modem, router, computer)

• Verify network settings (IP address, DNS servers)

• Contact Internet Service Provider (ISP) for assistance

IP stands for Internet Protocol. It is a set of rules that governs the format of data sent over the internet.

• IP is responsible for routing data packets between devices on a network.

• There are two versions of IP: IPv4 and IPv6.

• IPv4 uses 32-bit addresses and can support up to 4.3 billion unique addresses.

• IPv6 uses 128-bit addresses and can support an almost infinite number of unique addresses.

• IP is a layer 3 protocol in the OSI model.

• IP addresses can be static or dynamic, and ca...read more

NAT/PAT stands for Network Address Translation/Port Address Translation. It is used to translate private IP addresses to public IP addresses and vice versa.

• NAT/PAT is used to conserve public IP addresses by allowing multiple devices to share a single public IP address.

• It provides security by hiding the internal IP addresses of a network from the external network.

• NAT translates the private IP addresses of devices in a local network to a public IP address when communicating wit...read more

IP stands for Internet Protocol. It is a set of rules that governs the format of data packets sent over a network.

• IP is responsible for addressing and routing packets across the internet.

• There are two versions of IP: IPv4 and IPv6.

• IPv4 uses 32-bit addresses and supports approximately 4.3 billion unique addresses.

• IPv6 uses 128-bit addresses and supports an enormous number of unique addresses.

• IPv6 was introduced to address the depletion of IPv4 addresses.

A packet travels over two systems by following the OSI model for network communication and the TCP/IP model for internet communication.

• Packet is created at the application layer in the OSI model

• It then moves down through the transport, network, data link, and physical layers in the OSI model

• At the TCP/IP model, the packet moves through the application, transport, internet, and network access layers

• Each layer adds its own header information to the packet

• Example: A user sends a...read more

Firewalls are security systems that monitor and control incoming and outgoing network traffic. IPS and IDS are intrusion prevention and detection systems that analyze network traffic for malicious activity.

• Firewalls act as a barrier between a trusted internal network and untrusted external networks.

• IPS (Intrusion Prevention System) actively monitors network traffic for potential threats and takes action to prevent them.

• IDS (Intrusion Detection System) passively monitors netwo...read more

DNS stands for Domain Name System. It is a decentralized 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.

• The DNS process involves recursive and iterative queries.

• DNS caching is used to improve performance and reduce network traffic.

• DNS records like A, CNAME, MX, etc., store information about a domain.

• DNSSEC provides security by digita...read more

To configure DHCP in a router through CMD, use the 'ip dhcp pool' command and specify the network and default gateway.

• Open CMD and access the router's CLI

• Enter 'enable' to access privileged mode

• Enter 'configure terminal' to enter global configuration mode

• Enter 'ip dhcp pool [pool name]' to create a DHCP pool

• Specify the network and default gateway using the 'network' and 'default-router' commands

• Exit configuration mode and save changes with 'exit' and 'write memory'

• Example: 'i...read more

To configure VLAN in a router through CMD, use the 'vlan' command and specify the VLAN ID and name.

• Open CMD and connect to the router's console

• Enter 'enable' to access privileged mode

• Enter 'configure terminal' to enter global configuration mode

• Enter 'vlan [VLAN ID]' to create the VLAN

• Enter 'name [VLAN name]' to assign a name to the VLAN

• Exit configuration mode by entering 'exit'

• Save the configuration by entering 'write memory'

• Example: 'vlan 10' and 'name Sales' will create a V...read more

Electricity is generated at power plants using various sources like coal, natural gas, or renewable energy. It is then transmitted through power lines to homes and businesses. In a computer, electricity is converted into readable form through components like the power supply, motherboard, and processor.

• Electricity is generated at power plants using sources like coal, natural gas, or renewable energy

• It is transmitted through power lines to homes and businesses

• In a computer, el...read more

DHCP stands for Dynamic Host Configuration Protocol. It is a network protocol that assigns IP addresses to devices on a network.

• DHCP automates the process of assigning IP addresses to devices on a network.

• It helps to avoid IP address conflicts and makes it easier to manage a large network.

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

• Without DHCP, network administrators would have to manually assign IP addresses to each de...read more

OSPF is a routing protocol used in computer networks to determine the best path for data to travel.

• OSPF stands for Open Shortest Path First

• It is a link-state routing protocol

• OSPF routers exchange information about the network topology to determine the best path for data to travel

• There are several stages in OSPF: neighbor discovery, database synchronization, and route calculation

• OSPF uses a hierarchical structure with areas to reduce the amount of routing information that need...read more

The port number used by DHCP is 67 (server) and 68 (client).

• Port 67 is used by DHCP server to listen for client requests

• Port 68 is used by DHCP client to send requests to the server

• DHCP uses UDP protocol for communication

Data link layer is responsible for transferring data between adjacent network nodes and detecting errors in transmission.

• Data link layer is the second layer of the OSI model.

• It provides a reliable link between two devices over a physical layer.

• It is responsible for framing, error detection and correction, flow control, and access control.

• Examples of data link layer protocols include Ethernet, Wi-Fi, and PPP.

• Data link layer devices include switches and bridges.

A firewall is a network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules.

• Firewalls can be hardware or software-based

• They can be used to block unauthorized access to a network or specific devices

• Firewalls can also be used to restrict access to certain websites or applications

• Examples of popular firewall software include Norton, McAfee, and Windows Firewall

• Firewalls are an important component of network secur...read more

To troubleshoot BGP going down, check BGP neighbor status, analyze BGP routing table, verify BGP configuration, and check for any network connectivity issues.

• Check BGP neighbor status to see if the neighbors are up and if there are any flaps

• Analyze BGP routing table to identify any inconsistencies or missing routes

• Verify BGP configuration for any errors or misconfigurations

• Check for any network connectivity issues such as link failures or routing protocol mismatches

Yes, I have a good understanding of C programming and principles.

• I have experience in writing C programs for various applications.

• I am familiar with the syntax and structure of C programming language.

• I understand the principles of data types, variables, functions, and control structures in C.

• I have worked with C libraries and APIs.

• I rate myself 8 out of 10 in C programming.

To share a printer in a network, you need to set up printer sharing and configure the necessary settings.

• Connect the printer to a computer that will act as the print server

• Enable printer sharing on the computer

• Configure the printer settings on the print server

• Add the shared printer to other computers on the network

• Test the printer to ensure it is working properly

Modulation techniques are used to encode information onto a carrier signal for transmission over a communication channel.

• Modulation techniques vary in terms of the type of carrier signal used (analog or digital), the type of modulation (amplitude, frequency, phase), and the complexity of the modulation scheme.

• Examples of modulation techniques include amplitude modulation (AM), frequency modulation (FM), phase modulation (PM), and quadrature amplitude modulation (QAM).

• Modulati...read more

OSPF, ISIS, and BGP are three essential protocols in the Networking domain.

• OSPF (Open Shortest Path First) is a link-state routing protocol used for interior routing within a single autonomous system.

• ISIS (Intermediate System to Intermediate System) is a link-state routing protocol used for interior routing within a single autonomous system.

• BGP (Border Gateway Protocol) is a path-vector routing protocol used for routing between autonomous systems.

• OSPF and ISIS are used for in...read more

RIP, OSPF, EIGRP, and BGP are all routing protocols used in networking.

• RIP is a distance-vector protocol that uses hop count as its metric.

• OSPF is a link-state protocol that uses cost as its metric.

• EIGRP is a hybrid protocol that uses both distance-vector and link-state characteristics.

• BGP is an exterior gateway protocol used for routing between different autonomous systems.

• RIP and OSPF are used within a single autonomous system, while EIGRP and BGP are used between different...read more

Routers connect different networks, switches connect devices within a network, and hubs connect devices to a network.

• Routers operate at the network layer and use IP addresses to forward packets between networks.

• Switches operate at the data link layer and use MAC addresses to forward frames within a network.

• Hubs operate at the physical layer and simply broadcast data to all connected devices.

• Routers can provide security by blocking unwanted traffic, while switches and hubs can...read more

I would start by checking the physical connections, then troubleshoot the network devices and configurations.

• Check physical connections (cables, modem, router)

• Restart network devices (modem, router)

• Check network configurations (IP settings, DNS settings)

• Run network diagnostics tools (ping, traceroute)

OSI model is a conceptual framework for understanding network communication. Satellite communication is a type of wireless communication.

• OSI model has 7 layers, each with a specific function in network communication

• Networking involves connecting devices to share resources and information

• Satellite communication uses satellites to transmit signals over long distances

• Satellite communication is used for TV broadcasting, GPS, and internet access in remote areas

GSM and CDMA are two different technologies used in mobile communication.

• GSM uses SIM cards while CDMA does not.

• GSM allows for easy switching of phones while CDMA does not.

• GSM has better international roaming capabilities than CDMA.

• CDMA has better call quality and network capacity than GSM.

• GSM is more widely used globally while CDMA is mostly used in the US and parts of Asia.

DNS is a system that translates domain names to IP addresses. DHCP assigns IP addresses to devices. FSMO is a role in Active Directory. Cluster is a group of servers working together.

• DNS stands for Domain Name System and is responsible for translating domain names to IP addresses.

• DHCP stands for Dynamic Host Configuration Protocol and assigns IP addresses to devices on a network.

• FSMO stands for Flexible Single Master Operations and is a role in Active Directory that controls ...read more

To check IP route through CMD, use the 'route print' command.

• Open Command Prompt

• Type 'route print' and press Enter

• The IP route table will be displayed

• You can filter the results using various parameters like destination IP, interface, etc.

BGP is a routing protocol used to exchange routing information between different networks on the internet.

• BGP stands for Border Gateway Protocol.

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

• BGP is a path-vector protocol, which means it selects the best path for data to travel based on a number of factors such as shortest path, least number of hops, etc.

• BGP is used by internet service providers (ISPs) to exchange routing information with each other.

• B...read more

DHCP assigns IP addresses, DNS translates domain names to IP addresses, VLAN separates network traffic, IPv4 has 32-bit addresses, IPv6 has 128-bit addresses.

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

• DNS (Domain Name System) translates domain names to IP addresses.

• VLAN (Virtual Local Area Network) separates network traffic into different segments.

• IPv4 has 32-bit addresses, allowing for approximately 4.3 billion unique ...read more

ITIL fundamentals are a set of best practices for IT service management.

• ITIL stands for Information Technology Infrastructure Library

• It includes processes for service strategy, design, transition, operation, and continual improvement

• ITIL helps organizations align their IT services with business needs and improve efficiency

• Examples of ITIL processes include incident management, problem management, and change management

Alarms related to fiber cut can vary depending on the network infrastructure.

• Loss of signal alarm

• Optical power alarm

• High bit error rate alarm

• Path protection switch alarm

• Equipment failure alarm

VLAN stands for Virtual Local Area Network. It is used to logically segment a network into smaller broadcast domains.

• VLANs are created by configuring network switches.

• Devices in the same VLAN can communicate with each other as if they are on the same physical network.

• VLANs can improve network performance and security by reducing broadcast traffic and isolating network traffic.

• VLANs can be used to group devices by department, function, or security level.

• VLANs can span multiple...read more

Routers connect multiple networks, switches connect devices within a network, L3 switches combine routing and switching functions, repeaters amplify signals, hubs simply broadcast data to all connected devices.

• Routers connect multiple networks and make decisions about the best path for data to travel.

• Switches connect devices within a network and use MAC addresses to forward data to the correct destination.

• L3 switches combine routing and switching functions, allowing for more ...read more

Switches operate at layer 2 of the OSI model and forward data based on MAC addresses, while routers operate at layer 3 and forward data based on IP addresses.

• Switches operate at layer 2 of the OSI model, while routers operate at layer 3.

• Switches forward data based on MAC addresses, while routers forward data based on IP addresses.

• Switches are used to create LANs, while routers are used to connect different networks.

• Switches are typically used within a single network, while ro...read more

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

• OSPF is used to efficiently route traffic in large networks by calculating the shortest path between routers.

• It is a link-state routing protocol that uses Dijkstra's algorithm to determine the best path.

• OSPF is preferred over other routing protocols like RIP due to its faster convergence time and scalability.

• It supports VLSM (Variable Length Subnet Masking) and ...read more