Top 115 CCNA Interview Questions & Answers

Basic CCNA Interview Questions with Answers.


CCNA Interview Questions & Answers

Here some basic CCNA interview Questions & Answers and this is help you in CCNA exam. But before we reading this topic, we have learned some of basic CCNA related certification.

CCNA is an IT certification from Cisco. There are certain levels in CCNA. These Industry leading networking certifications are into divided 3 levels like Associate Level, Professional Level & Expert Level.

• CCNA: – Cisco Certified Networking Associate.
A beginner level certification & we have learn like Cloud, Collaboration, Cyber Operation, Data Center, Industrial, Routing & Switching, Security, Service Provider and Wireless Network.

• CCNP: – Cisco Certified Network Professional.
This is a Professional level Cisco Certification, a successor of CCNA, those students are deeper understanding of each concept on this certification.

• CCIE: – Cisco Certified Internetwork Expert.
This is a highest-level Cisco certification and very difficult to achieve. It is world most demanded, highest paying job.

Covered CCNA certifications exams: –
Routing Technologies, LAN Switching Technologies, Network Fundamentals, Network Access, WAN Technologies, IP Services, IP Connectivity, Security, Fundamentals, Automation and Programmability, Infrastructure Security, Infrastructure Services, Infrastructure Maintenance, Infrastructure Management.

CCNA Interview Questions and Answers 2023

Q1. What is CCNA?
Ans: – CCNA stands for Cisco Certified Network Associate. It is a one of the popular certifications in Information Technology for computer networking people from cisco system. It certifies a technician’s ability to understand install/ uninstall, setup configures, troubleshoots problems and operated a medium sized routed and switched computer network.

Q2. What is the Router User Mode?
Ans: – This mode is used to Login to be Router.
Command: –

Q3. What is Router Privileged Mode?
Ans: – This mode is used to see all router configurations.
Command: –

Q4. What is Router Global Configuration Mode?
Ans: – This mode is used to configure the router globally.
Command: –
Router (Config)#

Q5. What is different between User mode & Privileged mode?
Ans: – In User mode, no configuration can made but some commands of Privilege mode can change the configuration. We can only check the reachability and some basis commands in User mode but in Privilege mode we save, delete and modify the configuration filter.

Q6. Give some description about Telnet Remote service?
Ans: –
It is a TCP oriented service.
Its port no. is 23.
It creates session in clear text.
No encryption is there.
It can be used from both Windows, Linux and Mac system.
It is a remote connection protocol.

Q7. Give some description about SSH remote service?
Ans: –
Secure Shell (SSH) is a protocol which provides a secure remote access connection to network devices.
It is using TCP and its port no. 22.
It is more secure then Telnet.
It is use cryptographic algorithm to encrypt session.
It encrypts password using RSA (River Shamir Addelman) algorithm.

Q8. What is RSA Algorithm?
Ans: – RSA algorithm is a public key encryption technique and it is the most secure way of encryption process. In 1978, it was invented by Rivest, Shamir and Addleman and that’s way this name is RSA algorithm.

Q9. Give some description about TACACS+?
Ans: –
It’s full from Terminal Controller Access Control System plus.
It uses TCP service.
It is Cisco proprietary, but it uses with Kerberos and Microsoft network.
It is an additional, authentication, authorization, accounting service for providing secure remote access.
This service is known as AAA service (Authentication, Authorization and Accounting).

Q10. What is Routing?
Ans: – Routing is a process by which we make two or more different networks communicate. The devices named router are used for routing process and these devices are network layered of OSI model to complete the process.

CCNA Routing Interview Questions and Answers

Q11. What is Switching?
Ans: – Switching is the forward or exchange the data packets/ signals from one point to another point.

Q12. What are the types of Routing?
Ans: – There are 3 types of routing –
• Static Routing
• Dynamic Routing
• Default Routing

Q13. What is Static Routing? What are disadvantages of Static Routing uses?
Ans: –
Here routers are added manually by the administrator.
Here administrator overhead is high.
It is can be configured low end router.
It is secure & fast.
Mandatory need of destination network ID.
Administrator distance for Static Routing is 0 & 1.

Disadvantage: –
It is used for small network.
Everything to manually configure.
Network changes affect the complete network.

Q14. What is Default Routing?
Ans: –
It is the last preferred routing.
It is done between companies EDGE router/ Gateway router and Service Provider router (ISP).
It is configured for unknown destinations.
It helps in reducing the size of your routing table.

Q15. What is Dynamic Routing? Advantage of Dynamic Routing?
Ans: –
This is the most advance routing.
Here, Administrator need to advertise only the connected networks in the router.
Here, no need to know the other unknown networks.
Routing protocol will find out how to reach to other networks.
Some protocols are RIP, EIGRP, OSPF, BGP, Is-Is.

Advantage: –
There is no need to know the destination network.
Need to advertise directly connected networks.
Updates the topology changes dynamically, Administrator work is reduced.
Used for large organizations.
Neighbor routers exchange routing information and build the routing table automatically.

Q16. What is Routing Protocol & Routed Protocol?
Ans: –
• Routing Protocol: – Routing protocol will calculate the best path for source to destination for data delivery.
Example: – RIP, RIPv2, OSPF, BGP, Is-Is.

• Routed Protocol: – Routed protocol will carry the data from source to destination.
Example: – IP, IPX, XNS, Apple Talk.

Q17. What are types of Dynamic Routing protocol?
Ans: – Dynamic Routing protocol are 3 types –

1) Distance Vector Routing Protocol.
Example: – RIP, RIPv2, IGRP.

2) Link State Routing Protocol.
Example: – OSPF, IS-IS.

3) Hybrid or Advanced Routing Protocol.
Example: – EIGRP.

Q18. What are the features of Distance Vector Protocol?
Ans: –
It works with Bellman Ford Algorithm.
It performs periodic updates.
It uses classful routing protocol.
Its full routing table are Exchanged.
Its updates are through Broadcast (
It also known as “Routing by Rumor”.
Example: – RIP, IGRP.

Q19. What is the feature of Link State Protocol?
Ans: –
It works with Dijkstra or SPF (Shortest Path First) algorithm to find the best path to a destination.
It performs link state updates.
It uses classless routing protocol.
Here missing route are exchanged (incremental update).
It also known as “Routing by Intelligence”.
Example: OSPF, Is-Is.

Q20. What are the features of Hybrid protocol or Advance Distance Vector protocol?
Ans: –
It works with DUAL algorithm (Diffuse Update Algorithm).
It uses classless routing protocol.
Here missing route are exchanged.
Its updates are through multicast.
It also known as “Routing by Intelligence”.
Example: EIGRP.

Q21. What is Bellman Ford algorithm?
Ans: – Bellman Ford algorithm is used to calculate routes, based on the distance. This distance is replaced by more accurate values to reach the correct solution. The true distance is replaced by its old value with the length of a new path.

Q22. What is Dijkstra’s algorithm?
Ans: – Dijkstra’s algorithm is used to find the shortest path between the nodes in a network. Based on the shortest path, it creates the path tree and forwards the packet to the network.

Q23. What is DUAL?
Ans: – Diffusing Update Algorithm (DUAL) is used by the EIGRP routing protocol. It creates loop free network, routing and selecting the best path to destination network.

Q24. What is Autonomous System?
Ans: –
It is a logical group where routes are exchanged between routers.
It is a unique number identifying the routing domain of the routers.
An autonomous system is a collection of networks under a common administrative domain.
It ranges from 1 – 65535.

Q25. Comparison of different Dynamic Routing protocol?
Ans: –

Routing ProtocolAD ValueMetricPeriodic UpdatesAlgorithm
RIP120Hop CountYes
RIPv2120Hop CountYes
OSPF110Cost, BandwidthYes
Multicast to
EIGRP90Bandwidth, Load,
Delay, Reliability

Q26. What is Triggered Update?
Ans: –
Triggered update allows a device to advertise routing information changes immediately, which speeds up network convergence.

Q27. What is the type of Gateway protocol?
Ans: –
It is 2 types –

IGP (Interior Gateway Protocol): –
It handles routing within a single autonomous system.
Example: – RIP, IGRP, EIGRP and OSPF.

EGP (Exterior Gateway Protocol): –
It handles routing between different autonomous systems.
Example: – BGP.

Q28. What is the difference between an IGP and an EGP?
Ans: –
An Interior Gateway Protocol (IGP) is a routing protocol that routes within an autonomous system but an Exterior Gateway Protocol (EGP) is a routing protocol that routes between Autonomous systems.

Q29. What is AD value (Administrative Distance)?
Ans: –
Administrative Distance is a measure of the trustworthiness if the source of the routing information.
The number is between 0 to 255.
Less value is more trusted.

Q30. What is the different protocol of AD value?
Ans: –

Routing ProtocolAdministrative Distance
Directly Connected0
Static Route1
Internal EIGRP90
External EIGRP170

Q31. What is Metrics?
Ans: –
Metrics are used to make routing decisions in a router and it is the variable used in the algorithm. When calculate routing decisions, every routing protocol uses different metrics to choose the best path.
Example – Bandwidth, Delay, Path Cost & MTU.

Q32. What is Bandwidth?
Ans: –
Bandwidth is defined as the amount of data that can be carried from one node to another node within a time period. Bandwidth is normally expressed as bits per second (bps), Megabits per second (Mbps) and Gigabits per second (Gbps).

Q33. What is Delay?
Ans: –
Delay is defined as how long the bit of data travels between source and destination nodes. Normally it is measured in Seconds.

Q34. What is Path Cost?
Ans: –
Path Cost is determined based on the bandwidth of the links.

Q35. What is MTU (Maximum Transmission Unit)?
Ans: –
The Maximum Transmission Unit (MTU) is the size of the protocol data unit that can travel through the communication. MTU is associated with interfaces like NIC and serial ports.

Q36. What is RIP? What are the features of RIP?
Ans: –
Routing Information Protocol (RIP) is a Dynamic protocol. It is used to find the best path or route from source to destination over a network by using a routing metrics/ hop count algorithm.

Features: –
It is an Open Standard protocol.
It is 2 version (RIPv1 – Classful & RIPv2 – Classless).
It is a Dynamic and Distance Vector routing protocol.
Its updates are Broadcasted (
Its Administrative Distance is 120.
Its metric Hop Count.
Its maximum Hop Counts 15.
Its maximum routers 16.
Its Load Balancing of 4 equal paths.
It is used for small organizations.
It exchanges the entire routing table for every 30 seconds.

Q37. What is RIP Request & RIP Response message types?
Ans: –

• RIP Request message type: –
In this type of message forwarding, RIP enabled routers to sends a request message to the next connected router for a dynamic update using the Broadcast message

• RIP Response message type: –
Here, the next router replies via a Broadcast message with its connected route information.

Q38. What are RIP Update timers?
Ans: –
Every 30 seconds the entire routing table is updated to neighbor routers.

Q39. What are RIP Invalid/ Hold timers?
Ans: –
180 seconds time a router waits to gets updates, if no updates receive within 180 seconds the route is marked as unreachable (16th Hop).

Q40. What are RIP Route Flash timers?
Ans: –
240 seconds the marked unreachable route will be cleared from the routing table.

Q41. What is different between RIPv1 & RIPv2?
Ans: –

The original specification of RIP.To overcome insufficiencies of the original RIP specification, RIPv2 was developed.
It supports only classful routing (does not support VLSM).It supports classless routing (support VLSM).
Here, No authentication.Here, Authentication is available.
It uses Broadcast for RIP updates.It uses Multicast for RIP updates instead of Broadcast.
It sends routing updates periodically every 30 seconds as broadcasts, using along with the destination IP address.It sends routing updates as multicast traffic at the destination, multicast address of
It does not support Triggered updates.It is supports a Triggered update.

Q42. What is Topological Database?
Ans: –
A Topological Database is a collection of information gathered from LSAs.

Q43. What is the SPF algorithm (Dijkstra algorithm)?
Ans: –
The Shortest Path First (SPF) algorithm is a calculation performed on the database resulting in the SPF tree.

Q44. What is Routing Table?
Ans: –
A list of the known paths and interfaces stored in the Routing Table.

Q45. What is OSPF? What are the features of OSPF?
Ans: –
OSPF stands for Open Shortest Path First. It is a link-state routing protocol that can connect a large number of networks without having any limitation to the number of hops.

Features: –
It was developed by IETF (Internet Engineering Task Force).
It is the successor of RIP.
It is a classless routing protocol.
It is an Open Standard protocol, not Cisco proprietary.
It uses SPF algorithm (Dijkstra algorithm), developed by Edger Dijkstra.
It is a Link State routing protocol.
It works with Link State Advertisements.
• Here update is through Multicast (
Its AD value is 110.
Hello packets are sent every 10 seconds.
Here Area 0 is called the Backbone Area.
Unlimited Hop count.
Metric is Cost.
It supports VLSM and CIDR.
It supports only equal-cost load balancing.
It Incremental updates.

Q46. Give some characteristics of DR & BDR?
Ans: –

The router having the highest priority is DR.
The router with the second-highest priority is BDR.
The default priority value is 1.
In the case of a tie, the router with the highest router ID is DR and the second-highest router ID becomes the BDR.
If router priority is 0 it cannot become the DR & BDR.
Router which is not a DR or BDR is called DROTHER.
DR & BDR election is not preemptive.

Q47. What is Hello Protocols?
Ans: –
Hello Protocols provides dynamic neighbor discovery and it also maintains neighbor relationships, when a hello goes from an OSPF-enabled router to a designated router it uses and address to reach and when it goes from DR to the client it uses

Q48. What is EIGRP (Enhanced Interior Gateway Routing Protocol)? What are the features of EIGRP?
Ans: – This is a Cisco proprietary enhanced distance vector routing protocol.

Feature: –
It is a Hybrid (Advanced Distance Vector) routing protocol.
It is used in large networks.
It provides classless routing protocol/ VLSM support.
It gives an auto summarization feature.
It supports IP, IPX, and Apple Talk protocols.
It uses Diffusing Updates Algorithm (DUAL) for best-path selection.
It uses Reliable Transport Protocol (RTP) for communication.
It AD value 90.
It has the maximum Hop Count 255 but default 100.
It provides a Hello packet for Neighbor discovery in every 5 seconds.
It supports equal-cost and unequal cost load balancing.

Q49. What is RTP (Reliable Transport Protocol)?
Ans: –
RTP is used in EIGRP for reliable connection-oriented communication. It simply provides sequencing and acknowledgment for EIGRP packets between neighbors.

Q50. What is EIGRP K-value? Define the different types of K-value?
Ans: –
EIGRP metric value is called K-value.

K1Bandwidth (Value – 1)
K2Load (Value – 0)
K3Delay (Value – 1)
K4Reliability (Value – 0)
K5MTU (Value – 0)

CCNA 200 – 301 Interview Questions and Answers

Q51. What are tables are maintained in EIGRP?
Ans: –
EIGRP maintains are 3 tables –
• Neighbor Table: – Contains a list of directly connected routers.
• Routing Table: – The best route to the destination.
• Topology Table: – List of all the best routes learned from each neighbor.

Q52. What is Successor Route & Feasible Successor Route?
Ans: –

• Successor Route: – This is the best route as per the DUAL algorithm which is stored in the routing table.

• Feasible Successor Route: – This is the second-best route but it is kept in the topology table. If the successor route goes down then it is going to be injected instantly to the routing table.

Q53. What is Load Balancing?
Ans: –
Load Balancing is the process of sending packets over multiple paths to the same destinations.

Q54. What is Equal Cost Load Balancing & Unequal Cost Load Balancing
Ans: –

• Equal Cost Load Balancing: – The EIGRP has the capability to distribute traffic over all routers that have the same metric for the target destination, this is known as Equal Cost Load Balancing.

• Unequal Cost Load Balancing: – The EIGRP can distribute traffic over routers that have different metrics, this is known as Unequal Cost Load Balancing.

Q55. What is the difference between equal-cost and unequal-cost load balancing?
Ans: –
Equal-cost load sharing distributes traffic equally among multiple paths with equal metrics. Unequal-cost load sharing distributes packets among multiple paths with different metrics.

Q56. What is the EIGRP packet format?
Ans: –
There are 5 packet formats –
• Update.
• Query.
• Reply.
• Hello.
• Ack.

Q57. What is BGP? What are the features of BGP?
Ans: –
BGP (Border Gateway Protocol) is an exterior gateway protocol used to connect two or more different autonomous systems. It has an AD value of 20 for external routes and 200 for internal routes.

Features: –
It is an Open Standard protocol.
It is a TCP-oriented protocol that uses port no. 179.
It is an Exterior Gateway routing protocol.
Designated for Inter-As domain routing.
Designated to scale huge inter-network like the internet.
It is a Classless protocol.
It Updates are incremental and trigger.
path vector protocol.
It Metric is Attributes.
It sends updates to manually defined neighbors as unicast.
It AD value – 20 (E-BGP) & 200 (I-BGP).

Q58. What are the types of BGP?
Ans: –
There are 2 types of BGP –
• E-BGP (External BGP)
• I-BGP (Internal BGP)

Q59. What is ACL? Classification of ACL?
Ans: –
ACL (Access Control List) is a list of conditions that are used to filter packets.
ACL are 2 types –
• Name ACL: –
It is 2 types – Standard Name ACL & Extended Name ACL

• Number ACL: –
It is 2 types – Standard Number ACL & Extended Number ACL

Q60. What are the features of Numbered ACL?
Ans: –

• Numbered ACL has a unique number to all ACLs.
• Addition or deletion in not possible, the whole list must to deleted and recreated.

Q61. What is the feature of Named ACLs?
Ans: –

Named ACL is identified by a unique name which is unique.
The naming is based on the function of that access list.
Addition or deletion of a specific line is possible.

Q62. Where do we use Standard ACL?
Ans: –
Standard ACL is used to source IP addresses to filter traffic.

Q63. Where do we use Extended ACL?
Ans: –
Extended ACL is used to source IP address & destination IP address.

Q64. What is the difference between Standard & Extended ACLs?
Ans: –

Standard ACLExtended ACL
Filter based on the source.Filter based on the source and destination.
Permits or denies the entire TCP/ IP protocol suite.Action a specific IP protocol and port number.
The normal range is 1 to 99.The normal range is 100 to 199.
The expended range is 1300 to 1999.The expended range is 2000 to 2699.

Q65. What is NAT? Advantages & disadvantages of using NAT?
Ans: –
Network Address Translation (NAT) is also one of the IP services. This service is used to translate a private IP address to a public IP address.

Advantage: –
It prevents the depletion of global IPv4 addresses.
It provides additional security. (The original source and destination address are hidden)
It increases flexibility when connecting to the public internet.
• It allows the use of a private IPv4 addressing system and prevents internal address changes if users change the service provider.

Disadvantage: –
NAT consumes a lot of processor and memory because it translated the IP addresses of all incoming and outgoing datagrams.
Sometimes it comes delays in communication.

Q66. What are the types of NAT?
Ans: –
There are 3 types of NAT –
• Static NAT
• Dynamic NAT

Q67. What is Static NAT?
Ans: –
Static NAT is also called ‘Inbound Mapping’. It is the process of mapping an unregistered IP address to a registered IP address on a one-to-one basis.

Q68. What is Dynamic NAT?
Ans: –
Dynamic NAT maps private IP addresses to public addresses. Dynamic NAT uses a pool of public addresses and assigns them on a first-come, first-serve basis.

Q69. What is PAT (Port Address Translation)?
Ans: –
NAT overload is also called PAT, which maps multiple unregistered or private IP addresses to a single registered or public IP address by using different ports.

Q70. What is Frame Relay?
Ans: –
Frame Relay is a wide area network technology that is used to specify the Physical and Data Link layers (OSI model) of digital telecommunications changes using packet switching.

Q71. What is X.25?
Ans: –

This is a protocol used for packet switching across computer networks.
The X.25 protocols work on the Physical, Data Link, and Network layers of the OSI model.
Each X.25 packet contains a maximum of 128 bytes of data.
It is used in ATM networks, a variety of mainframe terminal or server applications and credit card verification networks.

Q72. What is ISDN?
Ans: –
ISDN (Integrated Services Digital Network) is a system of digital phone connections. This system allows voice and data to be transmitted simultaneously across the world using end-to-end digital connectivity.

Q73. What is VPN?
Ans: –
A VPN (Virtual Private Network) is a private network that uses a public network to connect remote sites or users together.

Q74. What is AAA?
Ans: –
It is a service to use in TACACS. It is Authentication, Authorization, and Accounting (AAA) services for providing secure remote access.

Q75. What is an AAA server?
Ans: –

AAA is a server program used to handle user requests to access computer resources in an enterprise.
It provides Authentication, Authorization, and Accounting (AAA) services.
The AAA server interacts which network access, gateway servers, database and directories containing the user’s information.
The current standard by which devices or applications communicate Dial-in User Service (RADIUS).

Q76. What is PPP?
Ans: –
Point to Point Protocol (PPP) is an Open Standard Protocol. It supports authentication and compression. It is a Data Link layer protocol of the OSI model. Internet Service Providers (ISP) have used these protocols for customer dial-up access to the internet.

Q77. What are the types of PPP?
Ans: –
There are 2 types of authentication in PPP –
• PAP (Password Authentication Protocol)
• CHAP (Challenge Handshake Authentication Protocol)

Q78. What is PAP?
Ans: –

It sends username and password are in cleartext.
It is an insecure protocol.

Q79. What is CHAP?
Ans: –

It sends username in clear text and password in encrypted form.
It is a secure protocol.

Q80. What is MPLS?
Ans: –
Cisco IOS MPLS (Multiple Protocol Label Switching) enables enterprises and service providers to build next-generation intelligent networks that deliver a wide variety at advanced, value-added services over a single infrastructure.

Q81. What is ‘Vty’?
Ans: –
The ‘Virtual tty’ line is a virtual connection. This line is used for a Telnet or SSH login to a router. Different routers and switches can have different numbers of connections in the VTY port.

Q82. What is Radius?
Ans: –

Remote Authentication Dial-in User service encrypts just the password and uses UDP.
It is a generic standard that uses centralized authentication when more than one remote access server is being used.
Database is maintained on the RADIUS server, instead of maintaining a database of authorized users on each remote access server.
All remote access servers forward their authentication request to this RADIUS server.

Q83. What is EtherChannel?
Ans: –
EtherChannel is a port-channel technology developed by Cisco. It is a technology that can logically group several first or gigabit ethernet ports into one logical channel. It works on the Data Link layer of the OSI model.

Q84. What is CRC?
Ans: –
Data communicated through the network, may have errors in it. One way of checking for errors in the transmitted data is by using the Cyclic Redundancy Checking (CRC) method.

Q85. What is the mean of these terms’ Multicast, Unicast, Anycast and Broadcast?
Ans: –

Multicast: –It is used to specify one-to-one communication.
Unicast: –It is used to specify one-to-group/ many communications.
• Broadcast: –It is used to specify all communications.
Anycast: –It is used to specify one-to-nearest association communication.

Q86. What is different between RIP & IGRP?
Ans: –
RIP will depend on the number of hops for the determination of the best route to the network. In IGRP, several factors like Reliability, Bandwidth, Hops Count and MTU are considered to decide the best route to the network.

Q87. What is PoE?
Ans: –
PoE stands for Power Over Ethernet. It will be used to pass the electric signal with the data at a time.

Q88. What are the different types of passwords that are used to secure the Cisco router?
Ans: –
There are 5 types of passwords are used to secure Cisco router –
• Consol
• Aux
• Vty
• Enable password
• Enable Secret

Q89. What are the main function of the router?
Ans: –

Packet Switching
Packet Filtering
Internetwork Communication
Path Selection
Quality of Service

Q90. What is the function of CDP?
Ans: –
CDP stands for Cisco Discovery Protocol that is a Data Link layer (OSI model) protocol and works on the basis of MAC address. It is also used to find out port numbers, ios details, IP address, switch modules, router models, interface details, and device ID.

Q91. What is Latency?
Ans: –
Latency is considered the amount of time delay. It can be measured as the time difference between the time when the network will receive data and when it will be sent by another network.

Q92. What is VLAN?
Ans: –
VLAN is a Virtual LAN. It is also called a switch inside the switch. We create our switch port into different VLANs to divide a single broadcast domain into the different broadcast domains.

Q93. What is the Backbone Area?
Ans: –
Area 0 is in OSPF is called as Backbone Area as to avoid loop mechanism every area must pass traffic from Backbone Area.

Q94. What is BPDU?
Ans: –
BPDU or Bridge Protocol Data Unit is original of an 802.1d standard. It is a type of STP message which switches use to exchange information of each other. BPDU contains information that helps the switch to determine the topology. The topology BPDU is sent in every 2 sec.

Q95. What is BPDU Guard?
Ans: –
BPDU Guard is used for protecting the switch port which is using the port fast.

Q96. What is STP?
Ans: –
STP (Spanning Tree Protocol) is a Cisco proprietary switching protocol that is used to avoid loops in the switching environment. The new version is IEEE802.1d. STP is a bridge-to-bridge protocol used to maintain a loop-free network.

Q97. What is Frame Relay?
Ans: –
Frame Relay is a packet-switching technology, it is used to join two or more routers with a single interface. It is cheaper in cost belongs to ISP.

Q98. What is HSRP?
Ans: –
Hot Standby Router Protocol (HSRP). HSPR is a redundancy protocol developed by Cisco to provide gateway redundancy without any additional configuration on the end devices in the subnet.

Q99. What is BootP?
Ans: –
BootP is a short form of Boot Program. It is a protocol that is used to boot diskless workstations connected to the network. BootP is also used by the diskless workstations to determine their own IP address and also the IP address of the server PC.

Q100. What is HDLC?
Ans: –
HDLC stands for High-Level Data Control protocol. It is the property protocol of Cisco which is the default encapsulation operated with Cisco routers.

Q101. What are the different memories used in a Cisco router?
Ans: –

• NVRAM: – NVRAM stores the startup configuration file.
• DRAM: – DRAM stores the configuration file that is being executed.
• Flash Memory: – Flash memory stores the cisco ios.

Q102. What is NVRAM?
Ans: –
NVRAM stands for Non-Volatile Random-Access Memory.
It is used to store the startup configuration file even if the router shuts down.

Q103. What is Checksum?
Ans: –
Checksum is nothing but a code or count of bits that were transmitted with the data and then the receiver can check that code or count of bits.

Q104. What is Route Poisoning?
Ans: –
Route Poisoning is used to prevent the router from sending packets to the invalid route within the network. Normally, this is used in a Distance Vector Routing protocol. This technique is used in order to prevent problems caused by inconsistent updates on a route.

Q105. What is VTP (VLAN Trunking Protocol)?
Ans: –
VTP is a Cisco proprietary protocol. It is used to share the VLAN configuration with multiple switches and to maintain a large network with many interconnected switches.

Q106. What is IEEE502.1Q or dot1q?
Ans: –
This is a Standard protocol for trunking multiple VLANs between cross-platform switches. 802.1Q is the IEEE standard for frame tagging on a trunk and supports up to 4096 VLANs.

Q107. What is Bridge ID?
Ans: –
A Bridge ID is a single 8-byte value that consists of two fields. They are Bridge Priority & Mac addresses.

Q108. What is Bridge Priority?
Ans: –
The Bridge Priority is a 2-byte value assigned to the switch. It is a value existing between 0 to 65535. The default value is 32768.

Q109. Name of the Router Port and their function?
Ans: –

Port Function Color
Power Port To provide Electricity.
Console PortTo provide Administration/
To configure the device and Password recovery.
Sky Blue
Ethernet PortIt is used to connect LAN to the Router.
4 type –
10BaseT -It is known as an Ethernet port.
100BaseT -It is a Fast Ethernet port.
1000BaseT -It is a Gigabit Ethernet port.
10000BaseT -It is a 10 Gigabit Ethernet port.
Auxiliary PortIt is known as Remote Administrative Port & used for remote administration or connect a modem to the router.Black
Serial PortIt is known as a WAN port.
It is used to connect to another Router. It is 2 types –
Serial Port – 60 pins & Speed is Less.
Smart Serial – 26 pins & Speed is Higher.
USB PortIt is used to connect any USB device.
BRI PortIt is used to connect the ISDN devices.

Q110. What is Aux Port?
Ans: –
This is also known as an Auxiliary port. This is also a physical access port on the router. Not every router has this port. It is a backup configuration port for the console and it also uses configure a password.

Q111. What is Auto Summarization?
Ans: –
Auto Summarization will summarize the classless subnets into classful subnets automatically. There are some routing protocols that have these features. Example – RIP & EIGRP.

Q112. What is Wildcard Mask?
Ans: –
Wildcard Masks are used to specify a range of network addresses. They are commonly used with routing protocols like OSPF and access list. It is 32 bits long like a subnet mask. It acts as an inverted subnet mask, but with a wildcard mask, the zero bits indicate that the corresponding bit position must match the same bit position in the IP address. The one bit indicates that the corresponding bit position doesn’t have to match the bit position in the IP address.

Q113. What is Syslog?
Ans: –
Syslog is using as the popular server to store the log files, usually known as a Syslog server. Most network equipment, like routers and switches, can send Syslog messages. Not only that, but Unix/ Linux servers also have the ability to generate Syslog data.

Q114. What is PuTTY?
Ans: –
PuTTY is an Open Source application or it is a terminal emulator and network file transfer application. We use this application to make communication between the Switch and your PC.

Q115. Comparison of data speeds by various generation mobile technology?
Ans: –

SymbolStandardFull NameMaximum Download Speed (Theoretical)Maximum Upload Speed (Theoretical)
2GGSMGlobal System for Mobile Communications14.4 kb/s14.4 kb/s
GGPRSGeneral Packet Radio Service53.6 kb/s26.8 kb/s
EEGDEEnhanced Data rates for GSM Evolution217.6 kb/s108.8 kb/s
3GUMTSUniversal Telecommunications System384 kb/s128 kb/s
HHSPAHigh Speed Packet Access7.2 Mb/s3.6 Mb/s
H+HSPA+High Speed Packet Access Release28.0 Mb/s5.76 Mb/s
4GLTELong Term Evolution100 Mb/s50 Mb/s
4GLTE-ALong Term Evolution Advanced150 Mb/s50 Mb/s

CCNA Interview Questions and Answers PDF

Also Read: –
Top 160 Networking Interview Questions & Answers
Top 60 Linux System Administrator Interview Questions
Top 50 Linux Interview Questions & Answers
Computer Hardware MCQ Questions & Answers
Cisco Router ports Function
VLAN trunking protocol-vtp
VLAN in network
Computer network switching function technics mode
Cisco router, ports, function

Conclusion: – These CCNA questions and answers help you in networking interviews. I suggest all the students, at first read carefully the CCNA related books, clear the concept, and then read this blog. “Good luck with your interview”.

—–Thank You—–

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