1. How many (minimum and maximum) ports are present in a router?

Please answer to this question

2. What is the draw back of OSPF protocol?

i) Single Area

ii) High Hardware Requirements

iii) Troubleshooting

3. Which protocol comes under Hybrid dynamic type?


4. Which protocol works only on Cisco routers?


5. What is the size of Hello Packets in EIGREP protocol?


6. How much hold down time of EIGREP protocol?


7. What is Formula of Hold down time of EIGRP protocol?


8. After how long EIGRP protocol Advertise its routing table?


9. Which multicast IP EIGRP protocol use?

10. Which protocol called Rapid protocol?


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11. What is the name of Algorithm of EIGRP protocol?


12. How many hop counts are by default and how much you can increase in EIGRP protocol?

By default 100 counts, and maximum 25

13. How much internal and External AD of EIGRP protocol?

Internal =90 and Externa =170

14. What is the name of best path in EIGRP protocol?


15. What is the second best path name of EIGRP?


16. When DR communicate with BDR which multicast ip it use?

17. What is the command for change serial cost?

IP OSPF COST (which want to set)

18. If bandwidth will increase what will happen?


19. What is the default bandwidth size of T1 Routers?

1544 BYTES

20. What is hold down time formula of OSPF?


21. How many types of OSPF Configuration?

There are Two Types



22. What is default cost of serial interface in OSPF?


23. On which bas OSPF take decision?


24. Wild card mask always in odd value or even?


25. On which interface we always Apply Access-List?

Fast Ethernet

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26. What is the default behavior of Access-List?


27. When we use extended Access-List?

When there is source and Destination

28. When we use standard Access-List?

When there is no Destination

29. What is the difference between named and Extended ACL?

In named Access-list we can edit and also give name

30. 2500 value in which type of Access list?


31. 1900 value in which type of Access list?


32. 1350 value in which type of Access-list?


33. Which protocol can do load balancing on unequal cost also?


34. In EIGRP metric parameters which 2 Options are enable by default?

i) Bandwidth

ii) Delay

35. What is the matric of EIGRP protocol?

i) Bandwidth

ii) Load

iii) Delay

iv) Reliability

v) MTU

vi) Maximum Transmission Unit

36. What is the draw back of EIGRP protocol?


37. Which type of updates EIGRP protocol do?


38. After how long keep alive messages exchange in EIGRP?


39. How many types of ends in WAN?

i) DTE (Data Terminal Equipment

ii) DCE (Data Communication Equipment)


40. Which 2 Protocols are in WAN technology?

i) HDLC ( High Level Data Link Control )

ii) PPP (Point to Point Protocol)

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41. What is overlaod?

It's another name of PAT (Port Address Translation)

42. How many types of NAT?

i) Static

ii) NAT

iii) Dynamic NAT

iv) PAT (Port Address Translation)

43. Which reserve port NO HTTP use?


44. Which reserve port Number Talent use?


45. What does EQ means?


46. In port based Access-List which command u give instead of IP?


47. In which Access- list type you can't do editing?

Standard and Extended

48. In stead of wild card mask what u can write after IP?


49. Which peer authentication method and which IPSEC mode is used to connect to the branch locations? (Choose two)

A - Digital Certificate
B - Pre-Shared Key
C - Transport Mode
D - Tunnel Mode
E - GRE/IPSEC Transport Mode
F - GRE/IPSEC Tunnel Mode

Answer: B D

50. Which algorithm as defined by the transform set is used for providing data confidentiality when connected to Tyre?


*Answer: D


In the site-to-site VPN branch we see something like this but in the Tranform Set sub-branch, we see

so the answer should be ESP-3DES-SHA2 or ESP-3DES?

To answer this question, we should review the concept:

“Data confidentiality is the use of encryption to scramble data as it travels across an insecure media”. Data confidentiality therefore means encryption.

“The transform set is a group of attributes that are exchanged together, which eliminates the need to coordinate and negotiate individual parameters”. In the picture above, we can see 3 parts of the transform-set ESP-3DES-SHA2:

IPsec protocol: ESP
IPsec encryption type: 3DES
IPsec authentication: SHA2

The question wants to ask which algorithm is used for providing data confidentiality (encryption), therefore the answer should be D - ESP-3DES.

51. Which defined peer IP address an local subnet belong to Crete? (Choose two)

Chat Room

IPSEC related questions and their answers

* Question

Which IPSec rule is used for the Olympia branch and what does it define? (Choose two)

A - 102
B - 116
C - 127
D - IP traffic sourced from destined to will use the VPN.
E - IP traffic sourced from destined to will use the VPN.
F - IP traffic sourced from destined to will use the VPN.

Answer: B E


From the output above, we learn that the IPSec Rule is 116. Next click on “IPSec Rules” and select the Name/Number of 116 to view the rule applied to it. You will see a “permit” rule for traffic from to (notice that the picture shown the wildcard masks, which are inverse subnet masks)


Which defined peer IP address an local subnet belong to Crete? (Choose two)

A - peer address
B - peer address
C - peer address
D - subnet
E - subnet
F - subnet

Answer: A D

52. Which IPSec rule is used for the Olympia branch and what does it define? (Choose two)

A - 102
B - 116
C - 127
D - IP traffic sourced from destined to will use the VPN.
E - IP traffic sourced from destined to will use the VPN.
F - IP traffic sourced from destined to will use the VPN.

Answer: B E

53. What is the difference between simple authentication and MD5?

MD5 encrypted form and simple authentication in clear text form

54. Which protocols do periodically updates?

Distance vector

55. What is Trigger RiP and from which IOS version it starts?

As link down it removes from its routing table - Version = 12.4

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56. How many hope count Rip or Rip2 can send updates?

15 hope count

57. Define Class full Protocol?

Which protocols advertise their networks without subnet mask.

58. Explain load balancing?

When data divide in different paths

59. How many maximum paths you can give on Latest IOS in RIP?

0 to 15

60. Why we use filter option?

When we specifically block, one router update for other routers

61. What is the name of distance vector algorithm?


62. On which base distance vector choose best path?

HOPE count

63. What is matric?

Formula of path selection

64. Which Dynamic Type draw back is, if single link down, it removes its routing table?

Distance Vector

65. Which protocols are link states?


66. What is difference between RIP and RIPv2?


No authentication
Support FLSM


Support VLSM

67. Explain protocol?

Set of rules

68. Which protocol used before part of CCNA?


69. Which command we give for live view of remote site routers?

Terminal monitor

70. Why we use debug command?

For live view

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71. What is difference between IGP and EIGRP?

IGP = use in Autonomous and EIGP = use with multiple autonomous

IGP= Interior gateway routing protocol.

EIGRP= Enhanced Interior Gateway routing protocol

72. What is difference between routing and routed protocols?

i) Routing use for best path selection

ii) Routed protocol keeps source and destination information.

73. When we do default route?

When there is multiple destination and single gateway.

74. How many parts of Ping?

Tow parts - eco and eco reply

75. Which type of routing you did in CCNA?

Traditional Routing

76. What is difference between static and dynamic routing?

In Static route we add others connected network and in dynamic, we advertise our network

77. What does routing mean?

For best path selection

78. What does synchronization mean?

Routers are ready to communication with each other

79. Which command we give for see routing table?

Show ip route

80. Which command we give if router IOS stucked?

Crl +Shift+F6 and X

81. When written <CR > what does it mean?

Command complete

82. Interface 0/0 what does it mean?

Card number / card interface number

83. What s the formula for metric of OSPF?


84. What is refresher?

Every 30 min of topology table exchange time called refresher OR

Exchange time of topology table in OSPF protocol called refresher

85. After how long OSPF exchange its topology table?

After 30 min

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86. What are partial updates?

Any change in network

87. Which updates called incremental updates?

Change based

88. Which table find best path?

Routing table

89. When OSPF protocol advertise its routing table?

When it discover neighbor with the help of hello packets

90. How many tables are in OSPF protocol?


1- Neighbor

2- Topology

3- Routing

91. What is default time of hello packets in OSPF?

10 sec

92. What is default size of Hello packets in OSPF?

50 bytes

93. What is name of OSPF Algo?

Dijecstra or SPF (shortest part first)

94. What is difference between FLSM and VLSM?

In FLSM subnet mask of all subnets will b same. But in
FLSM it varies.

95. What is CIDR?

Class Less Inter domain Routing Protocol - another name of Supernetting.

96. What is subnetting?

Subnetting is tool reduce the wastage of IP

97. Do we subletting of IP?

NO, we do subletting of NID

98. How many potions of IP?

Two portions of IP. Network and host

99. Which classes are assignable?

A, B and C

100. Which company mange IP's?

IANA (Internet Assigned Number of Authority)

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101. What is the minimum and maximum request timer?

Minimum = 180 sec
Maximum = 300 Sec

102. When IP confliction accord in subnet which IP assigned automatically and what it called?

169.254.x.x APIPA (Automatic Private Internet Protocol address)

103. When we use loop back IP?

For Self hardware test

104. Which mode we can't skip when we come back from interface mode?

2nd mode we can't skip

105. Which command we give on privilege mode for coming back to user execution mode?


106. On Which mode we give debug command?

Privilege mode / live view (2nd mode)

107. When we use interface mode?

For specific interface commands

108. Which mode called privilege mode?

Second mode

109. In which IOS version 182 people can access router through telenet?

Onward 12.2 version

110. What is IOS?

Internet Operating system. Its router's operating system.

111. How many ways to access router?

3 ways

i) Telnet (IP)

ii) AUX (Telephone)

iii) Console (cable)

112. Which cable we connect in DB-9?

Roll over calbe

113. Which cable called roll-over?

Console access able

114. How many types of Ethernet?

4 types

i) Ethernet

ii) Fast Ethernet

iii) Gigabit

iv) 10 Giga.

115. What cable called V.35?

Serial Connectivity cable

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116. Which works router Do?

1- Path selection and

2- Packet Switching {frame relay}

117. When we use Router?

For communication between different networks

118. How many types of router?

Two types

i) Modular

ii) Non-Modular

119. Which command we use for ping in IPv6?

Ping6 source IP -s Destination IP

120. What is loop back IP in IPV6?

::1 and ping 6

121. What we called 64 Bit Mac-address in IPV6?

EUI= Enhanced universal identifier - 16 bits add in IPv6 so it's called EUI

122. HUB in Star topology or Bus Topology?

In star topology, but logically works like a bus topology.

123. If there is only 2 Host in Bus Topology is that possible collision accord?

Yes, because end terminal will not absorb signals. Signal will be bounce back and collision will accord.

124. Which way of communication bus topology use?


125. What is the difference between half duplex and full duplex?

In half duplex, sender should b one. In full duplex, sender can be multiple.

126. Which Type of Transmission Bus Topology Support?

Half Duplex

127. What is Collision?

When signal hits each other, collision accord.

128. Types of Resource Sharing?

Intranet , Extranet and Internet .

129. Types of communication in IPv6 ?

Unicast, Multicast and Anycast

130. Explain Types of communication in IPv4?

Unicast, Multicast and Broad cast

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131. Define Network?

Communication, Resource sharing and Media (When multiple host share their resources with each other OR when multiple devices connect with each other for resource sharing )

132. What is quality of IPv6?

a) Router processing will rapid because field size wills 8 bytes (but in IPv4 it was 12 byres)

b) No Fragmentation

c) No Checksum

133. Which mathematically form used inIPv6?


134. How many fillers we can put in one IP of IPv6?

ONE (:: called filler)

135. Default Packet Size of IPv6?

8 Bytes = 16*8 =128 bit

136. What is MAC address size of IPv6?

64 bits

137. In which protocol supenetting is enable by default?


138. In which protocol you manually enable route summarization?


139. How many valid IP will b in /21 in route Summarization?


140. What will be the prefix length of 224 in VLSM?

27 (carry 3 bits from host (128+64+16=224) and add in network ports (24+3=27) )

141. What is the subnetmask of / 27 in network based and host based?

In network based 224 { 128+64+32}and in host based 248 (128+64+64+16+8)

142. How many broadcast domains are in Switch?


143. How many collision domains are in switch?

Equal number of ports

144. How ARP brings MAC address for switch?

Through Broadcast

145. On which base switches take decisions?

Mac Address

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146. If line up, but protocol down which layer should be troubleshot?

Data link problem - Layer 2

147. If line down and protocol also down; in this case which layer move problem?

Physical Layer - Layer 1

148. Which type for communication switch do?

In case of any new event switch do broadcast, after that always do Unicast.

149. What is CAM?

Content Address Memory. its another name of MAC address table.

150. Which protocol switch use for filling its MAC-Table?

ARP - Address Resolution Protocol

151. Is hub intelligent device?

No; because it not use header

152. What is the difference between bus topology and HUB?

Hub is Centralized device ( series ) .Bus topology is Decentralized device (in parallel)

153. What are the ranges of private IPS?

A Class = -
B Class = -
C Class = -

154. How many types of IPS?

Three Types of IP
1- Public
2- Private
3- Special IP

155. What is Syntax of IPV4?


156. What is the size of IPV4?

32 bits

157. Why IP address called logical address?

Private IP called logical address because they are change able.

158. How we can see MAC address from DOS Prompt?


159. Who controls MAC address uniqueness and how?

IEEE (Institute of Electrical Electronics and Engineering) Controls its uniqueness.
They divide 48 bits MAC address in two parts. First 24 bits part called OUI (Organizational unique identifier) and other 24 bits are device code.

160. Why MAC address called Physical address?

Because it's not changeable

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161. What is Size of IPv4 MAC Address?

48 Bits

162. What is BIA?

Burn in Address other name is MAC address

163. What is Encapsulation and De-encapsulation?

To send data called encapsulation and receive data called De-encapsulation.

164. What is FCS?

Frame Check Sequence -
CRC (Cyclic Redundancy Check) algorithm runs in switch that called FCS (Frame Check Sequence)

165. Which layer called error detection layer?

Data link layer

166. What is segmentation and fragmentation?

To divide data in pieces is called segmentation and divide segmentation in pieces called Fragmentation.

167. Do you know How many types of Data?

Voice, video, text

168. Which decision called socket base?

IP plus port (IP on layer 3 and port on Layer 4 - In Encapsulation, socket base decision on Network Layer -Layer 3)

169. Tell me How many reserve ports?

0 - 1023

170. Which layer are called upper layer?

a) Application Layer - 7
b) Presentation Layer - 6
c) Session Layer - 5

171. What is the default size of Frame?

1518 bytes

172. What is OSI?

Open System Interconnection. t was first name of 7 Layer

173. What is the IGP (Interior Gateway Protocol)?

Any protocol used by an internetwork to exchange routing data within an autonomous system. E.g. RIP, IGRP and OSPF.

174. What is the multicast routing?

Sending a message to a group multicast address is called multicasting, and its routing algorithm is called multicast routing.

175. What is the Virtual Path?

Along any transmission path from a given source to a given destination, a group of virtual circuits can be grouped together into what is called path.

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176. What is the Virtual Channel?

A logical circuit that is created by Virtual channel links. It carries data between two endpoints in a network.

The other name for Virtual Channel is Virtual Circuit.

177. What is the logical link control?

One of two sublayers of the data link layer of OSI reference model, as defined by the IEEE 802 standard. This sublayer is responsible for error detection but not correction, flow control and framing.

178. What is the difference between routable and non- routable protocols?

Routable protocols can work with a router and can be used to build large networks. Non-Routable protocols are designed to work on small, local networks and cannot be used with a router.

179. What is the MAU?

MAU - Multistation Access Unit

180. Explain 5-4-3 rule?

In a Ethernet network, between any two points on the network, there can be no more than five network segments or four repeaters, and of those five segments only three of segments can be populated.

181. What is the difference between TFTP and FTP application layer protocols?

TFTP - Trivial File Transfer Protocol
A stripped down version of FTP, easy to use and fast. TFTP has no Directory browsing, no Authentication and insecure it can only send and receive files.

FTP - File Transfer Protocol
The TCP/IP protocol used for transmitting files between network nodes. FTP allows access to both Directories and files, manipulating directories, typing file contents and copying files between hosts.

182. What is the difference between ARP and RARP?

ARP - Address Resolution Protocol
The protocol that traces IP addresses to MAC addresses.

RARP - Reverse Address Resolution Protocol
The protocol within the TCP/IP stack that maps MAC addresses to IP addresses.

183. What is the ICMP protocol?

ICMP - Internet Control Message Protocol
It is a Network Layer Internet protocol, which can report errors and status information. We can use the ping command to send ICMP echo request messages and record the receipt of ICMP echo reply messages. With these messages, we can detect network or host communication failures and troubleshoot common TCP/IP connectivity problems.

184. What is the MAC address?

The address for a device as it is identified at the Media Access Control (MAC) layer in the network architecture. MAC address is usually stored in ROM on the network adapter card and is unique.

185. What is the Attenuation?

In communication weakening or loss of signal energy, typically caused by distance.

186. What is the Cladding?

A layer of a glass surrounding the center fiber of glass inside a fiber-optic cable.

187. What are the NetBIOS and NetBEUI?

NetBIOS - Network Basic Input / Output System
An application-programming interface (API) that can be used by programs on a local area network (LAN). NetBIOS provides programs with a uniform set of commands for requesting the lower-level services required to manage names, conduct sessions, and send datagrams between nodes on a network.

NetBEUI - NetBIOS Extended User Interface
An improved version of the NetBIOS protocol, a network protocol native to Microsoft Networking. It is usually used in small, department-size local area networks (LANs) of 1 to 200 clients. It can use Token Ring source routing as its only method of routing.

188. What is the Beaconing?

An FDDI frame or Token Ring frame that points to serious problem with the ring, such as a broken cable. The beacon frame carries the address of the station thought to be down.

189. What is the Terminal Emulation, in which layer it comes?

The use of software, installed on PC or LAN server, that allows the PC to function as if it were dumb terminal directly attached to a particular type of mainframe.
Telnet is also called as terminal emulation. It belongs to application layer.

190. What is the Frame relay, in which layer it comes?

Frame relay is an industry standard, shared access, switched Data Link Layer encapsulation that services multiple virtual circuits and protocols between connected mechanism.
Frame relay is a packet-switched technology.

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191. What is the network Subnet?

A subnet is the subdivision of an IP network.

192. What is the network Brouter?

It's a Hybrid device that combines the features of both bridges and routers.

193. How network Gateway is different from Routers?

A device connected to multiple physical TCP/IP networks capable of routing or delivering IP packets between them.

It's a layer 3 device that connects 2 different networks and routes packets of data from one network to another. It breaks up Broadcast domain as well as Collision Domain.

194. What is the Mesh Network?

A network in which there are multiple network links between computers to provide multiple paths for data to travel.

195. What is Passive Topology in ccna?

When the computers on the network simply listen and receive the signal, they are referred to as passive because they don't amplify the signal in any way.

196. What are major types of Networks and explain?

Peer-to-Peer Network
Computers can act as both servers sharing resources and as clients using the resources.

Server-based Network
Provide centralized control of network resources and rely on server computers to provide security and network administration

197. What is Protocol Data Unit in ccna?

The processes at each layer of the OSI model.
Data Link-------Frames

198. What is difference between Baseband and Broadband Transmission in ccna?

In a baseband transmission, the entire bandwidth of the cable is consumed by a single signal.

In broadband transmission, signals are sent on multiple frequencies, allowing multiple signals to be sent simultaneously.

199. What are the possible ways of data exchange in ccna?

Possible ways of data exchange in ccna are

200. What is point-to-point protocol in ccna?

An industry standard suite of protocols for the use of point-to-point links to transport multiprotocol datagrams.

201. What are the two types of Transmission Technology available in ccna?

Two types of Transmission Technology available in ccna are Point - to - Point and Broadcast

202. What are 10Base2, 10Base5 and 10BaseT Ethernet LANs?

10Base2 an Ethernet term meaning a maximum transfer rate of 10 Megabits per second that uses baseband signaling, with a contiguous cable segment length of 200 meters (185mts). Known as Thinnet.

10Base5 an Ethernet term meaning a maximum transfer rate of 10 Megabits per second that uses baseband signaling, with a contiguous cable segment length of 500 meters. Known as Thicknet.

10BaseT an Ethernet term meaning a maximum transfer rate of 10 Megabits per second that uses two pairs of twisted-pair baseband signaling, with a contiguous cable segment length of 100 meters.

203. What is RAID in ccna?

A method used to standardize and categorize fault-tolerant disk systems. RAID levels provide various mixes of performance, reliability, and cost. Some servers provide three of the RAID levels: Level 0 (striping), Level 1 (mirroring), and Level 5 (striping & parity).

204. Difference between the Communication and Transmission?

Communication is the process of sending and receiving data by means of a data cable that is connected externally.
Transmission means the transfer of data from the source to the destination.

205. What is Subnetting? Why is it used?

Used in IP Networks to break up larger networks into smaller subnetworks. It is used to reduce network traffic, Optimized network performance, and simplify management i.e. to identify and isolate network problems.

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206. What is a VLAN? What does VLAN provide?

VLAN - Virtual Local Area Network
Vlan is a logical grouping or segmenting a network connected to administratively defined ports on a switch, they provide Broadcast control, Security and Flexibility.

207. What is PING utility?

PING - Packet Internet Gopher
A utility that verifies connections to one or more remote hosts. The ping command uses the ICMP echo request and echo reply packets to determine whether a particular IP system on a network is functional. Ping is useful for diagnosing IP network or router failures.

208. What is difference between Switch & Hub?

Switches operate at Layer 2 Data Link Layer
Address Learning
Forward / Filter decision using MAC address
Loop Avoidance
Breakup collision domains
Switches create separate collision domains but a single broadcast domain

Hub operates at Layer 1 Physical Layer
No Filtering
No Addressing
Hub creates single collision domain and single broadcast domain
Make forwarding to all the ports when signal is arrived