50+ IBM Interview Questions and Answers

Questions related to TCP/IP layers, subnet mask, VLAN, ARP, port number, IP and MAC addresses.

• Transport layer is needed for reliable communication and error correction.

• Subnet mask is used to identify the network and host portions of an IP address.

• VLAN is needed for network segmentation and security.

• Switches and routers send packets or frames based on destination IP address.

• Types of ARP include ARP request and ARP reply.

• Port number is used to identify the application or servic...read more

A ticket can be managed by following a systematic approach.

• Acknowledge the ticket and assign it to the appropriate team member

• Set a priority level based on the severity of the issue

• Communicate with the customer and provide regular updates

• Resolve the issue and close the ticket

• Document the entire process for future reference

The IP phone boot up process involves several steps to initialize the device and connect to the network.

• The phone powers on and performs a self-test

• It obtains an IP address from the DHCP server

• It downloads the firmware and configuration files from the TFTP server

• It registers with the call manager or PBX

• It is ready to make and receive calls

SIP call flow is the process of establishing, maintaining, and terminating a session initiated by Session Initiation Protocol (SIP).

• SIP INVITE message is sent from the caller to the callee

• Callee responds with a SIP 100 Trying message

• Callee sends a SIP 180 Ringing message to indicate the phone is ringing

• Callee sends a SIP 200 OK message to indicate the call is accepted

• Media negotiation takes place between the caller and callee

• Call termination is initiated by either party with ...read more

Private IP is used within a network while public IP is used to communicate over the internet.

• Private IP is assigned to devices within a local network and is not visible to the internet.

• Public IP is assigned by the internet service provider and is used to communicate over the internet.

• Private IP addresses are in the range of 10.0.0.0 to 192.168.0.0.

• Public IP addresses are unique and can be traced back to a specific device or location.

• Private IP addresses are used for internal ...read more

Modem connects to the internet, router connects devices to the network, switch connects devices to each other.

• Modem converts digital signals to analog for transmission over phone lines or cable lines.

• Router directs traffic between devices on a network and connects to the internet through a modem.

• Switch connects devices to each other within a network.

• Example: Modem - cable modem, Router - Linksys router, Switch - Netgear switch

L3 switch is a switch with routing capabilities while a router is a dedicated device for routing.

• L3 switch operates at layer 2 and layer 3 of the OSI model while a router operates only at layer 3.

• L3 switch can perform routing functions like a router but also has the ability to switch frames between ports like a switch.

• Routers are typically used to connect different networks while L3 switches are used to segment a network into smaller subnets.

• Examples of L3 switches include Ci...read more

A client can get an IP address through DHCP (Dynamic Host Configuration Protocol) or by manually configuring it.

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

• Clients can also manually configure their IP address, subnet mask, gateway, and DNS server

• IP addresses can be obtained through IPv4 or IPv6 protocols

Native VLAN is used for untagged traffic, default VLAN is used when no VLAN is specified, DHCP process involves client requesting IP address from server.

• Native VLAN is used for untagged traffic on a trunk port

• Default VLAN is used when no VLAN is specified, typically VLAN 1

• DHCP process involves client sending a DHCP discover message, server offering an IP address, client requesting the offered IP address, and server acknowledging the request

TCP 3 way handshake is a process of establishing a connection between two devices over a network.

• The client sends a SYN packet to the server

• The server responds with a SYN-ACK packet

• The client sends an ACK packet to the server to confirm the connection

• This process is used to ensure reliable communication between devices

Packet flow between same network involves communication between devices within the same IP subnet.

• Devices communicate directly without needing to go through a router.

• Packet headers contain source and destination IP addresses for proper routing.

• Switches forward packets based on MAC addresses within the same network.

• Firewalls may inspect and filter packets within the same network.

• Examples: File sharing between devices on the same LAN, printing to a network printer within the sa...read more

Packet flow between different networks involves routing, switching, and encapsulation.

• Packet travels from source device to destination device through routers and switches

• Routers determine the best path for the packet based on routing tables

• Switches forward the packet within the same network based on MAC addresses

• Encapsulation involves adding headers and trailers to the packet at each network layer

• Example: Packet from a computer in one network to a server in another network

The DORA process is used for IP address assignment in a network. It consists of four steps: Discover, Offer, Request, and Acknowledge.

• Discover: The client sends a broadcast message to find available DHCP servers.

• Offer: DHCP servers respond with an IP address lease offer.

• Request: The client selects an IP address and sends a request to the DHCP server.

• Acknowledge: The DHCP server acknowledges the request and assigns the IP address to the client.

IP and TCP headers explained with purpose of each field

• IP header contains source and destination IP addresses, version, header length, type of service, total length, identification, flags, fragment offset, time to live, protocol, header checksum

• TCP header contains source and destination port numbers, sequence number, acknowledgement number, data offset, reserved, flags, window size, checksum, urgent pointer

• Purpose of each field in IP and TCP headers is to provide necessary in...read more

BBU is connected to RRH using single-mode fiber optic cable.

• Single-mode fiber optic cable is used for long distance communication.

• It has a smaller core diameter than multimode fiber optic cable.

• It allows for higher bandwidth and longer transmission distances.

• It is commonly used in telecommunications and data centers.

• Examples of single-mode fiber optic cable include OS1 and OS2.

An IP address can be found by checking network settings on a device or using online tools.

• Check network settings on device (e.g. Windows: Control Panel > Network and Sharing Center > Change adapter settings)

• Use online tools like ipchicken.com or whatismyip.com

• Command prompt: type 'ipconfig' (Windows) or 'ifconfig' (Mac/Linux)

The power dbm in BBU to RRH is determined by the distance between them and the required signal strength.

• The power dbm is dependent on the distance between the BBU and RRH.

• The required signal strength also plays a role in determining the power dbm.

• Factors such as obstacles and interference can affect the power dbm.

• The power dbm can be adjusted through the use of attenuators or amplifiers.

ARP (Address Resolution Protocol) is used to map a network address (such as an IP address) to a physical address (such as a MAC address).

• ARP is used in Ethernet networks to find the MAC address of a device based on its IP address.

• When a device needs to send data to another device on the network, it sends an ARP request asking for the MAC address of the destination device.

• The destination device responds with its MAC address, allowing the sending device to send the data directl...read more

IPSEC messages are used for secure communication. Troubleshooting scenarios include connectivity issues and misconfigured settings.

• IPSEC messages are used to establish and maintain secure communication between two devices

• Common troubleshooting scenarios include connectivity issues, such as failed VPN connections

• Misconfigured settings can also cause IPSEC issues, such as incorrect encryption or authentication settings

• Tools such as packet captures and debug logs can be used to ...read more

The question covers various topics related to networking protocols and technologies.

• OSI layers: Understand the flow and purpose of each layer in the OSI model.

• DHCP & DHCP Relay: Know how DHCP works and the role of DHCP relay agents.

• DNS: Understand the DNS resolution process and various record types.

• TCP: Learn about TCP connection establishment, data transfer, and termination.

• HTTP & HTTPS: Understand the basics of HTTP and the differences with HTTPS.

• SSL/TLS Handshake: Know the...read more

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

• DNS is like a phonebook for the internet

• It helps to locate websites by translating domain names into IP addresses

• DNS servers store information about domain names and their corresponding IP addresses

• DNS queries are sent by web browsers to DNS servers to resolve domain names

• DNS can also be used for other purposes such as email routing and network diagnostics

WAN IP is the public IP address assigned to a network by the ISP, while IPv4 is a specific type of IP address used for identifying devices on a network.

• WAN IP is used for communication over the internet, while IPv4 is used for communication within a local network.

• WAN IP is unique to each network and can be dynamic or static, while IPv4 addresses are unique to each device on a network.

• Examples of WAN IP addresses include 203.0.113.1, while examples of IPv4 addresses include 19...read more

The blue screen of death is an error screen displayed on Windows operating systems when a fatal system error occurs.

• It is also known as a stop error or a system crash.

• It is typically caused by hardware or driver issues.

• When a blue screen of death occurs, the system is forced to restart.

• The error message displayed on the blue screen provides information about the cause of the crash.

• Examples of blue screen of death errors include DRIVER_IRQL_NOT_LESS_OR_EQUAL, PAGE_FAULT_IN_NON...read more

Yes, TCP Header Flags are used to control the flow of data between devices.

• TCP Header Flags are 6 bits long and are used to control the flow of data between devices.

• There are 6 TCP Header Flags: URG, ACK, PSH, RST, SYN, and FIN.

• URG is used to indicate that the data is urgent and should be prioritized.

• ACK is used to acknowledge receipt of data.

• PSH is used to push data to the receiving device.

• RST is used to reset the connection.

• SYN is used to synchronize sequence numbers.

• FIN is...read more

Forwarding, delegation, and stub zones are all methods of DNS resolution.

• Forwarding involves sending DNS queries to another DNS server for resolution.

• Delegation involves assigning responsibility for a subdomain to another DNS server.

• Stub zones are a copy of a zone's NS records used to reduce DNS query traffic.

• All three methods can improve DNS performance and reliability.

• Forwarding and delegation can be configured at the DNS server level.

• Stub zones are configured on the DNS cl...read more

I am flexible with shift timings and job location to ensure smooth operations and adaptability.

• I am open to working different shifts, including nights and weekends, to ensure 24/7 coverage for network security

• I am willing to relocate if necessary to take on new opportunities and challenges in different locations

• I understand the importance of being adaptable in the fast-paced field of network security

TLS Handshake is a process of establishing a secure connection between a client and a server.

• TLS Handshake involves a series of steps to establish a secure connection

• It includes negotiation of encryption algorithm, exchange of keys, and verification of digital certificates

• TLS Handshake ensures confidentiality, integrity, and authenticity of data transmitted over the network

• Examples of applications using TLS Handshake are HTTPS, SMTPS, FTPS, etc.

PUSH flag is used to indicate the start of a new TCP session while URG flag is used to indicate urgent data.

• PUSH flag is set when a sender wants to push data to the receiver without waiting for a full buffer

• URG flag is set when a sender wants to indicate that some data is urgent and should be processed immediately

• PUSH flag is used to initiate a new session while URG flag is used to indicate the presence of urgent data within an existing session

Encryption and deception of packet

• Encryption is the process of converting plain text into cipher text to protect data from unauthorized access

• Packet deception is a technique used to mislead attackers by sending fake packets to divert their attention

• Combining encryption and packet deception can enhance network security by making it difficult for attackers to intercept and decipher data

• Tools like honeypots and honeynets can be used for packet deception

TCP 3-way handshake is a process of establishing a connection between two devices. SSL handshake is a process of establishing a secure connection between a client and a server.

• TCP 3-way handshake involves SYN, SYN-ACK, and ACK packets exchanged between the client and server to establish a connection.

• SSL handshake involves exchanging certificates, negotiating encryption algorithms, and generating session keys.

• TCP 3-way handshake is used in TCP/IP protocol, while SSL handshake ...read more

32-bit and 64-bit refer to the size of the memory addresses used by a computer's processor.

• 32-bit systems can address up to 4GB of RAM, while 64-bit systems can address much larger amounts of RAM.

• 64-bit systems can handle larger files and perform more complex calculations than 32-bit systems.

• 64-bit systems provide better performance and can run 32-bit software as well.

• Some software may not be compatible with both 32-bit and 64-bit systems.

TCP/IP is a set of protocols that governs the way data is transmitted over the internet.

• TCP/IP stands for Transmission Control Protocol/Internet Protocol.

• It is a suite of communication protocols used to connect network devices on the internet.

• TCP ensures that data is reliably transmitted between devices.

• IP is responsible for addressing and routing data packets across networks.

• Examples of TCP/IP applications include web browsing, email, and file transfer.

Time Machine is a concept in science fiction that refers to a device or technology capable of traveling through time.

• Time Machine is a popular concept in science fiction literature, movies, and TV shows.

• It is often depicted as a device or technology that allows individuals to travel to the past or future.

• The concept of Time Machine was popularized by H.G. Wells' novel 'The Time Machine' published in 1895.

• Time travel in Time Machine can be achieved through various means such a...read more

Active Directory is a directory service developed by Microsoft for managing network resources and user accounts.

• Active Directory is used to centrally manage and authenticate users, computers, and other network resources in a Windows domain.

• It provides a hierarchical structure of objects, such as users, groups, and organizational units (OUs), which can be organized and managed based on administrative needs.

• Active Directory enables single sign-on (SSO) functionality, allowing u...read more

I will handle customers by providing timely and effective communication, understanding their needs, and offering solutions to their problems.

• Listen actively to understand customer concerns

• Communicate clearly and effectively to address customer needs

• Offer solutions and follow up to ensure customer satisfaction

The customer base of petrol pumps in my city consists of a diverse range of individuals and businesses who rely on fuel for transportation and other purposes.

• Individual car owners who need to refuel their vehicles regularly

• Commercial truck drivers who require fuel for their transportation businesses

• Motorcyclists and scooter riders who depend on petrol for their daily commute

• Delivery services and ride-sharing companies that need fuel for their operations

I expect a hike percentage that is in line with industry standards and my experience.

• I would like to discuss the salary range for this position and understand the company's compensation philosophy.

• Based on my research and experience, I would expect a hike percentage of around 10-15%.

• However, I am open to negotiation and would consider other factors such as benefits and growth opportunities.

• Ultimately, my priority is to join a company where I can contribute my skills and grow ...read more

GSM architecture refers to the network structure of a GSM system.

• Consists of three main components: Mobile Station, Base Station Subsystem, and Network and Switching Subsystem

• Mobile Station includes the physical device and SIM card

• Base Station Subsystem includes Base Transceiver Station and Base Station Controller

• Network and Switching Subsystem includes Mobile Switching Center, Home Location Register, and Visitor Location Register

• Allows for communication between mobile device...read more

BSOD stands for Blue Screen of Death. It is an error screen displayed on Windows operating systems when a system error occurs.

• BSOD is caused by hardware or software issues

• To resolve BSOD, try restarting the computer or running a system diagnostic

• Update drivers and software to prevent future BSODs

• Examples of BSOD errors include IRQL_NOT_LESS_OR_EQUAL and SYSTEM_SERVICE_EXCEPTION

IPv4 uses 32-bit addresses while IPv6 uses 128-bit addresses.

• IPv4 uses a 32-bit address format, allowing for approximately 4.3 billion unique addresses.

• IPv6 uses a 128-bit address format, allowing for an enormous number of unique addresses.

• IPv4 addresses are written in decimal format (e.g., 192.168.0.1), while IPv6 addresses are written in hexadecimal format (e.g., 2001:0db8:85a3:0000:0000:8a2e:0370:7334).

• IPv4 has a limited address space and is running out of available addres...read more

The TEC difference between 2G, 3G, and 4G refers to the technological advancements and capabilities of each generation.

• 2G (Second Generation) technology primarily focused on voice communication and introduced digital encryption.

• 3G (Third Generation) technology brought faster data transfer speeds, enabling internet access and video calling.

• 4G (Fourth Generation) technology further improved data speeds, allowing for high-quality video streaming and online gaming.

• Each generation...read more

OSPF and EIGRP are both routing protocols used in computer networks, but they differ in several ways.

• OSPF is a link-state protocol, while EIGRP is a distance-vector protocol.

• OSPF uses a hierarchical network design, while EIGRP uses a flat network design.

• OSPF supports multiple paths to a destination, while EIGRP only supports a single path.

• OSPF uses a metric based on bandwidth, while EIGRP uses a composite metric based on bandwidth, delay, reliability, load, and MTU.

• OSPF is an...read more

To resolve network issues, start by identifying the problem and then troubleshoot using various tools and techniques.

• Identify the problem by checking network connectivity, IP addresses, and DNS settings.

• Use network diagnostic tools like ping, traceroute, and nslookup to troubleshoot.

• Check network hardware like routers, switches, and cables for any issues.

• Update network drivers and firmware to ensure they are up-to-date.

• Reset network settings or restart network devices if nece...read more

DHCP process is a network protocol that dynamically assigns IP addresses to devices on a network.

• DHCP client sends a broadcast request for an IP address to DHCP server

• DHCP server receives the request and offers an IP address

• DHCP client accepts the offer and requests the IP address

• DHCP server assigns the IP address to the client

• DHCP client acknowledges the assignment

I address escalations by actively listening, empathizing, investigating root causes, collaborating with stakeholders, and implementing solutions.

• Listen to the concerns of the parties involved

• Show empathy and understanding towards the situation

• Investigate the root causes of the escalation

• Collaborate with all stakeholders to find a resolution

• Implement solutions to prevent future escalations

IPSEC VPN is a secure network connection that uses encryption and authentication to protect data transmitted over the internet.

• IPSEC VPN stands for Internet Protocol Security Virtual Private Network.

• It provides secure communication between two or more networks over the internet.

• IPSEC VPN uses encryption algorithms to ensure confidentiality of data.

• It also uses authentication protocols to verify the identity of the communicating parties.

• IPSEC VPN can be used to establish secur...read more

API flow involves passing data from controller to service layer for processing.

• Controller receives API request and extracts data

• Controller calls appropriate service method with the extracted data

• Service layer processes the data and returns the result to the controller

Yes, I have used maps extensively in my work as a GIS Engineer.

• I have experience working with various types of maps, including topographic, thematic, and digital maps.

• I have used maps to analyze spatial data and create visual representations of data.

• I have also used maps to perform geocoding and geolocation tasks.

• Examples of software I have used to work with maps include ArcGIS, QGIS, and Google Maps API.

Dependency injection is a design pattern in which components are given their dependencies rather than creating them internally.

• Dependency injection helps in achieving loose coupling between classes.

• It allows for easier testing and maintenance of code.

• There are three types of dependency injection: constructor injection, setter injection, and interface injection.

CSS elements are the building blocks of Cascading Style Sheets that define the appearance of HTML elements.

• CSS elements are used to style HTML elements

• They include selectors, properties, and values

• Selectors target specific HTML elements, while properties define their appearance

• Values determine the specific style of the property

• Examples of CSS elements include color, font-size, margin, padding, etc.

The working domain in my previous project was e-commerce

• Developed and maintained an online marketplace for various products

• Implemented payment gateway integration for secure transactions

• Designed and optimized the user interface for better user experience

I primarily work with tools such as LabVIEW, MATLAB, and Python for data analysis and automation.

• LabVIEW

• MATLAB

• Python

LVM commands for creating logical volumes

• Use 'pvcreate' to initialize physical volumes

• Use 'vgcreate' to create volume groups

• Use 'lvcreate' to create logical volumes within volume groups

• Use 'lvextend' to extend the size of logical volumes

• Use 'lvresize' to resize logical volumes

ARP, DNS, and DHCP are essential networking protocols that facilitate communication between devices on a network.

• ARP (Address Resolution Protocol) is used to map IP addresses to MAC addresses on a local network.

• DNS (Domain Name System) translates domain names into IP addresses to enable communication over the internet.

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

• ARP operates at the data link layer, DNS at the application ...read more