Get familiar with networking terms

Network :A network is just a collection of devices and end systems connected to each other and able to communicate with each other.There are two types of topologies in networking. 

The physical topology is what the network looks like and how all the cables and devices are connected to each other.
The logical topology is the path our data signals take through the physical topology.

Protocols are rules that govern how devices communicate and share information across a network. Examples of protocols include: 
• IP – Internet Protocol 
• HTTP - Hyper Text Transfer Protocol 
• SMTP – Simple Mail Transfer Protocol 

Multiple protocols often work together to facilitate end-to-end network communication, forming protocol suites or stacks. 

Network reference models were developed to allow products from different manufacturers to interoperate on a network. A network reference model serves as a blueprint, detailing standards for how protocol communication should occur. 

The Open Systems Interconnect (OSI) and Department of Defense (DoD) models are the most widely recognized reference models. 

Considerations in network
Speed –The biggest consideration
Delay – There must be specific delay for sending datas across the network.VOIP applications must follow time delay for proper communications
Availability – Network should be always available for applications accessing it 

Types of Networks
Local area networks (LANs) are used to connect networking devices that are in a very close geographic area, such as a floor of a building, a building itself, or a campus environment
Wide area networks (WANs) are used to connect LANs together. Typically, WANs are used when the LANs that must be connected are separated by a large distance.

A MAN (Metropolitan Area Network) is another category of network, though the term is not commonly  used. A MAN is defined as a network that connects LAN’s across a city-wide geographic area. 

An internetwork is a general term describing multiple networks connected together. The Internet is the largest and most well-known inter network. 

Some networks are categorized by their function, as opposed to their size. A SAN (Storage Area Network) provides systems with high-speed, lossless access to high-capacity storage devices. 

A VPN (Virtual Private Network) allows for information to be securely sent across a public or unsecure network, such as the Internet. Common uses of a VPN are to connect branch offices or remote users to a main office.

Methods of Network Communication
Unicast : One to One Communication.used in both IPv4 and IPv6
Broadcast: One to all communication.Used in Ipv4 only
Multicast : One to a group communication.Used in both IPv4 and IPv6
Anycast : One to nearest Communication.Used in Ipv6

Broadcast Domain : A logical division of network where all devices can reach each othjer by broadcast
Collision Domain : It is a logical seperation of a network where data packets will collide each other.when collision occur every devices in collision domain will get effected by it.

CSMA/CD : CSMA/CD (carrier sense muli access/Collision detection) is a protocol used in wired network/LAN to detect collision and over come it.CSMA/CD is only used in half duplex communication

Half-Duplex – hosts can transmit or receive, but not simultaneously
Full-Duplex – hosts can both transmit and receive simultaneously

CSMA/CA : (carrier sense muli access/Collision avoidance) is a protocol used in wireless network to avoid collision.

Ethernet is a family of technologies that provides data-link and physical specifications for controlling access to a shared network medium. It has emerged as the dominant technology used in LAN networking

Power over Ethernet (PoE) allows both data and power to be sent across the same twisted-pair cable, eliminating the need to provide separate power connections. This is especially useful in areas where installing separate power might be expensive or difficult.
PoE can be used to power many devices, including:
·         Voice over IP (VoIP) phones
·         Security cameras
·         Wireless access points

HUB : A hub is nothing more than a physical repeater, if it receives an electrical signal on one interface it will repeat it by sending it on all its interfaces except the one it originated from.There is no intelligence in a hub and it only operates on the physical layer of the OSI model.Hub have one broadcast domain and one collision domain 

Switches: Switches work in layer 2 and layer 3.Switches working in layer 3 have both routing and switching capacity.New switches work in full duplex mode.switches have one broadcast domain and mulitple collision domain.Collision domain is equal to number of active ports in that switch
there are three things that switches do that hubs do not:
·         Hardware address learning
·         Intelligent forwarding of frames
·         Loop avoidance 
Three types of layer -2 forwarding methods 

Cut-through switching: The switch will start forwarding the frame before the whole frame has entered the switch. The switch only needs to know the destination MAC address so as soon as it reads it it can start forwarding. This is fast but less reliable if you have corrupt frames.

Store-and-forward: The switch will receive the complete frame, check if it‟s errors free and then forward it. If it‟s corrupt it will be discarded.

Fragment-free: The switch will check if the first 64 bytes are OK, basically this is a trade-off between cut-through and store-and-forward switching. 

Routers: Routers interconnect networks and choose the best path to each network
Destination.Routers work on layer 3 ie network layer.Routers dont forward broadcasts.Routers are capable for seperating broadcast domains
Routers build routing tables to perform forwarding decisions, which contain the following:
·         The destination network and subnet mask
·         The next hop router to get to the destination network
·         Routing metrics and Administrative Distance 
The routing table is concerned with two types of Layer-3 protocols:

Routed protocols - assigns logical addressing to devices, and routes packets between networks. Examples include IP and IPX.

Routing protocols - dynamically builds the information in routing tables. Examples include RIP, EIGRP, and OSPF

Interview Questions
·         What is Routing?
·         What is Protocol?
·         Explain difference between Router,Switch and Hub ?
·         What is the difference between OSI and TCP/IP Model ?
·         What is the size of IP Address?
·         IEEE standard for wireless networking?
·         What is the range of class A address?
·         What is the range of class B address?
·         What is the range of class C address?
·         What is PoE (Power over Ethernet) ?
·         What is a peer-peer process?
·         What is the difference between broadcast domain and collision domain ?
·         What is ping? Why you use ping?
·         Explain difference between straight and cross over cable with examples ?
·         What is the difference between tracert and traceroute
·         What is Round Trip Time?
·         What is TTL ?
·         Define the terms Unicasting, Multiccasting and Broadcasting and Anycasting?
·         Where do we use cross and standard cable?
·         How many pins do serial ports of routers have?
·         What are the differences between static ip addressing and dynamic ip addressing?
·         What is APIPA?
·         Difference between CSMA/CD and CSMA/CA ?
·         What is DHCP scope?
·         What is Checksum?
·         What is  Redundancy ?
·         What are the criteria necessary for an effective and efficient network?
·         What is the key advantage of using switches?
·         When does network congestion occur?
·         Does a bridge divide a network into smaller segments?
·         What are the different memories used in a CISCO router?
·         What is BootP?
·         What are the different types of passwords used in securing a CISCO router?
·         What is the use of "Service Password Encryption" ?
·         Brielfly explain the conversion steps in data encapsulation.?
·         In configuring a router, what command must be used if you want to delete the configuration data that is stored in the NVRAM?
·         Differentiate Logical Topology from Physical Topology?
·         what is AS (Autonomous System) ?
·         What is the difference between Private IP and Public IP ?
·         Explain different cable types ?
·         How does RIP differ from EIGRP?
·         Differentiate User Mode from Privileged Mode
·         What is 100BaseFX?
·         Differentiate full-duplex from half-duplex ?
·         What is MTU?
·         What does the show protocol display?
·         What is HDLC?
·         What is PPP?
·         What is POP3 ?

For Complete list of Networking questions click here

Click here to View and download complete CCNA / CCNP notes and interview questions for $ 


  1. I am a disabled veteran from the US Army and I have been sick for awhile and I would like to know if my answers are right with these questions. Can you email me the answers that you have so I can match and see if what I have is right Please.

  2. Thank you very much Rudy

  3. Hello Sir, can you email me the answers for the questions posted above so that I may prepare myself for the interview way please...


  4. I don't understand why don't you just post the answers online as well?

  5. please email the answers to

    1. if u have answers for the questions posted above then plz send me on Email :

  6. Hi Shabeer,

    Could you please email the answers for the above interview questions.

    Email :

    With hope.....

  7. Dear Author,

    My name is Richard Ricard from US, I am teacher who teaches networking it would be great if you can email me the answers for this questions to my email id


  8. I have an interview with Cisco tomorrow and would love the answers to these questions (as a review). My email is This blog is an awesome review tool. Thanks.

  9. I just came across this blog and found it very very useful. Can you send me answers to the questions and also more questions that will help in crack the interview. Thank you very much for your help. my email id is

  10. Can you send me the answers. Appreciate your help.

  11. Hi Shabeer,

    Awesome work Bro, really appreciate the efforts you have put in, can you please email me the answers for all the interview questions which you have mentioned in the entire section, it will be really a great help. My email ID is

    Thanks & Regards,
    Sufyan Samar.

  12. Could you please send me the answers.

    1. You can buy it through paypal button at the bottom of this blog

  13. Please email me the answers.

  14. Please can you email me the answers too.

  15. Please ca you email me the answers too on

  16. This is awesome.. Keep up the good work :)

  17. plz email me as

    1. Hello sir,
      Could you please email the answers for the above interview questions.

    2. Hi Shabeer,

      Excellent, I am really appreciate the efforts you have, can you please email me the answers for all the interview questions which you have mentioned in the entire section, it will be really a great help to me. My email ID is

  18. Hi, great work can you please email

    1. You can buy entire notes and Q&A through paypal link mentioned in this blog

  19. Can someone please email the answer to the question @


  21. HI Sir,

    This is Anjaz khan

    Can u email all Questions and answers u have related to CCNA,


  22. can u send me answers for the questions posted above then plz send me on :P Email :

  23. Hello,

    Can you please email me all Questions and Answers related to CCNA on I have interview on Monday.

    Thanks and Regards

  24. Hello Sir,
    Please send me my email( above those answers.

  25. can you send me also the answer of thoes question, thanks,

  26. Very useful material

  27. Hey, can you send me the answers of those questions, Thanks,

  28. hi shabeer,

    tell me the procedure to get the pdf of ccna and ccnp pdf

    1. Please drop a email to shabeeribm @ .

  29. Hi Shabeer

    i am in bangarore.your notes is very good.

    i want to buy complete ccna & ccnp notes with all intv questions-answers.pls give me details how to pay.

    1. Please drop me a mail at

  30. Thank u boss....its very useful...... :)

  31. Please email me the answer thank you so much

  32. Could you please send me the answers to the above questions. Thanks in advance

  33. could you send me the answer of theas question. i am fresher my mail id is
    thank you sir

  34. Can someone email me the answers. Thank you so much. I really appreciate it.

  35. Hello Sir, can you email me the answers for the questions posted above so that I may prepare myself for the interview way please...
    E-mail id -

  36. Please Email me the answer for the above questions. Email ID:

    Thanks in advance for your time

  37. Can you email me the answer too :

  38. hello sir plz send me Question answer this me mail id thanks

  39. Hi,can you send me also the answer of those question, thanks,

  40. Can you send me the interview question & answer @ Thanks

  41. Hey i have a interview tomorrow can you please send me the interview questions to my email

  42. please share me answers i have interview my mail id

  43. please send me answers on

  44. thank u so much this is pretty good explanation.

  45. Can you please send the answers to

  46. Could you please email me answers to

  47. Hi can you send the answers to

  48. Hi, great work sir , can you please email me the answers to

  49. Hi Shabeer this is Gautam from Delhi I want to buy ccna and ccnp notes with questions and answers kindly send the procedure my email is