questions about networking

8/12/2019 Questions About Networking

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QUESTIONS WITH ANSWERS:

What is difference between Switch & Hub?

Switch:Switches operate at Layer 2 Data Link Layer

Address LearningForward / Filter decision using MAC addressLoop Avoidance

Breakup collision domains

Switches create separate collision domains but a single broadcast domain

Hub:Hub operates at Layer 1 Physical Layer

No FilteringNo Addressing

Hub creates single collision domain and single broadcast domainMake forwarding to all the ports when signal is arrived

What is PING utility?

PINGPacket Internet Gopher

A utility that verifies connections to one or more remote hosts. The pingcommand uses the ICMP echo request and echo reply packets to determine

whether a particular IP system on a network is functional. Ping is useful fordiagnosing IP network or router failures.

What is a VLAN? What does VLAN provide?

VLAN

Virtual Local Area NetworkVlan is a logical grouping or segmenting a network connected to administratively

defined ports on a switch, they provide Broadcast control, Security and Flexibility.


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What is Subnetting? Why is it used?Used in IP Networks to break up larger networks into smaller subnetworks. It isused to reduce network traffic, Optimized network performance, and simplify

management i.e. to identify and isolate network problems.

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.

What is RAID?A method used to standardize and categorize fault-tolerant disk systems. RAID

levels provide various mixes of performance, reliability, and cost. Some serversprovide three of the RAID levels: Level 0 (striping), Level 1 (mirroring), and Level

5 (striping & parity).

What are 10Base2, 10Base5 and 10BaseT Ethernet LANs?10Base2 an Ethernet term meaning a maximum transfer rate of 10 Megabits persecond 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 persecond that uses two pairs of twisted-pair baseband signaling, with a contiguous

cable segment length of 100 meters.


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What are the two types of Transmission Technology available?PointtoPoint and Broadcast

What is point-to-point protocol?An industry standard suite of protocols for the use of point-to-point links totransport multiprotocol datagrams.

What are the possible ways of data exchange?SimplexHalf-duplex

Full-duplex

What is difference between Baseband and Broadband Transmission?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.

What is Protocol Data Unit?The processes at each layer of the OSI model.

Layers PDUTransport Segments

Network Packets/Datagrams

Data Link FramesPhysical Bits


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What are major types of Networks and explain?Peer-to-Peer Network

Computers can act as both servers sharing resources and as clients using theresources.

Server-based NetworkProvide centralized control of network resources and rely on server computers to

provide security and network administration

What is Passive Topology?

When the computers on the network simply listen and receive the signal, they arereferred to as passive because they dont amplify the signal in any way.

What is Mesh Network?A network in which there are multiple network links between computers toprovide multiple paths for data to travel.

How Gateway is different from Routers?Gateway

A device connected to multiple physical TCP/IP networks capable of routing or

delivering IP packets between them.Router

Its 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 CollisionDomain.

What is Brouter?


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Its a Hybrid device that combines the features of both bridges and routers.

What is Subnet?A subdivision of an IP network.

What is 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.

What is Terminal Emulation, in which layer it comes?The use of software, installed on PC or LAN server, that allows the PC to functionas 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.

What is 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 stationthought to be down.

What are NetBIOS and NetBEUI ?NetBIOSNetwork Basic Input / Output System

An application-programming interface (API) that can be used by programs on alocal area network (LAN). NetBIOS provides programs with a uniform set of


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commands for requesting the lower-level services required to manage names,

conduct sessions, and send datagrams between nodes on a network.NetBEUINetBIOS 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 areanetworks (LANs) of 1 to 200 clients. It can use Token Ring source routing as its

only method of routing.

What is Cladding ?A layer of a glass surrounding the center fiber of glass inside a fiber-optic cable.

What is Attenuation?

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

What is 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.

What is ICMP ?ICMPInternet Control Message Protocol

It is a Network Layer Internet protocol, which can report errors and statusinformation. 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 andtroubleshoot common TCP/IP connectivity problems.

What is difference between ARP and RARP ?


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ARPAddress Resolution Protocol

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

The protocol within the TCP/IP stack that maps MAC addresses to IP addresses.

What is the difference between TFTP and FTP application layer protocols?TFTPTrivial File Transfer Protocol

A stripped down version of FTP, easy to use and fast. TFTP has no Directorybrowsing, no Authentication and insecure it can only send and receive files.

FTPFile Transfer ProtocolThe 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.

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 segmentsonly three of segments can be populated.

What MAU ?MAUMultistation Access Unit

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.

What is logical link control ?One of two sublayers of the data link layer of OSI reference model, as defined by


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the IEEE 802 standard. This sublayer is responsible for error detection but not

correction, flow control and framing.

What is 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.

What is Virtual Path ?Along any transmission path from a given source to a given destination, a groupof virtual circuits can be grouped together into what is called path.

What is multicast routing ?Sending a message to a group multicast address is called multicasting, and its

routing algorithm is called multicast routing.

What is IGP (Interior Gateway Protocol) ?Any protocol used by an internetwork to exchange routing data within an

autonomous system. E.g. RIP, IGRP and OSPF.

What is EGP (Exterior Gateway Protocol) ?It is the protocol the routers in neighboring autonomous systems use to identifythe set of networks that can be reached within or via each autonomous system.

What is Autonomous System ?A group of Networks under mutual administration that share the same routing

methodology. Autonomous Systems are subdivided by Areas and must beassigned an individual 16-bit number by the IANA.


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What is BGP (Border Gateway Protocol) ?

It is a protocol used to advertise the set of networks that can be reached within

an autonomous system. BGP enables this information to be shared with theautonomous system. This is newer than EGP (Exterior Gateway Protocol).

What is Gateway-to-Gateway protocol ?It is a protocol formerly used to exchange routing information between Internet

core routers.

What is Kerberos ?An authentication mechanism used to verify user or host identity. Kerberos uses

encryption to prevent intruders from discovering passwords and gainingunauthorized access to files.

What is OSPF (Open Shortest Path First) ?OSPF is the first Open Standard Link State Routing Protocol.

Its a Classless Routing Protocol meaning when updates are sent they send both

IP address and Subnet mask.Administrative Distance is 110.

Metric used is Cost i.e. Cost= 108

---------------BandwidthOSPF uses algorithm to build Routing Table called Dijisktra.

Sends only Incremental and Triggered updates. Route updates sent within therouters will be secured with the help of MD5 encrypted password.

Routing updates are sent as Multicast addresses i.e.224.0.0.5SPF (all OSPF routers)


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224.0.0.6Designated router and Backup Designated router

OSPF maintains 3 types of Routing table i.e. Routing Table (Dijisktra), TopologyTable (SPF) and Neighborship Table.

In OSPF Routers can be connected in two methods i.e.

Point-to-Point LinkPoint to Multipoint Link

In OSPF a single large Autonomous system is break into small areas. There

should be atleast one area by name Area 0. Its called as Backbone Area.

The Router that connects more than one Area is called as Area Border Routers.The Router that connects to other Autonomous system is called as Autonomous

System Boundary Router.

Router IDIf the priority is set 1 to all the routers then there is a tie in priority, in this case it

will check if there is any loopback address is given to any router if not the router

with highest value of IP address will be elected as Router ID.This router will be then called as Designated Router and the router with lessvalue of IP address after Designated Router will be called as Backup Designated

Router.

If a Router has all interfaces existing in single area than that router is called asInternal Router.

Whenever a router send routing updates to DR and BDR it uses Destination

address as 224.0.0.6 and when DR send updates to all the routers it usesDestination address as 224.0.0.5.

In OSPF routing updates are called as Link State Advertisements.

If an OSPF router wants to send updates to other OSPF router then it shouldcarry 3 requirements i.e.

Hello Packets ReceivedIt contains Area Id, Uptime, Password, Hello Interval, Dead Interval,

Neighborship Table and Router Id.

Point-to-Point Link Point to Multipoint Link

Halo Interval10 Halo Interval30Dead Interval40 Dead Interval120

Adjacency Built

If both router interfaces belongs to same Area, same Password then Hallo andDead Intervals should be set same.

Neighborship Built

If both routers are adjacent to each other then Neighborship is built in Routers.When one routerRA sends updates i.e. Link State Advertisements to other

routerRB it will send that update to Topology Database of routerRB and will runan algorithm SPF on routerRB to create a new Topology Table. After that Dijisktra


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Algorithm is run to find the best path and that entry will be put in Routing Table.

The router when sends Hallo packets to other router a Neighborship Table is seton that Router.

What is SLIP (Serial Line Internet Protocol) ?An industry standard serial encapsulation for point-to-point connections thatsupports only a single routed protocol, TCP/IP.

What is RIP (Routing Information Protocol) ?Rip run on any Routers hence called as Open Standard Distance Vector RoutingProtocol.

Its a classful routing protocol meaning when updates are sent they send only IP

address but not subnet mask.Administrative Distance is 120.

Metric used is Hop counts (number of routers to cross to reach the destination).Rip uses algorithm name Bellman Ford Algorithm to determine the best pathselection.

Supports maximum 15 Hops.

Supports 6 paths if there is a tie in metric i.e. same metric.

RIP TimersRoute update timer30secondsRoute invalid timer180 seconds

Holddown timer180 seconds

Route flush timer240 seconds

What is the HELLO protocol used for ?The HELLO protocol uses time instead of distance to determine optimal routing.

It is an alternative to the Routing Information Protocol.


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What is the difference between interior and exterior neighbor gateways ?Interior gateways connect LANs of one organization, whereas exterior gateways

connect the organization to the outside world.

What protocol do DNS name servers use ?DNS uses UDP for communication between servers. It offers a connectionless

datagram service that guarantees neither delivery nor correct sequencing of

delivered packets (much like IP).

What is a DNS resource record ?A resource record is an entry in a name server's database. There are several

types of resource records used, including name-to-address resolutioninformation. Resource records are maintained as ASCII files.

BOOTP helps a diskless workstation boot. How does it get a message tothe network looking for its ip address ?A protocol used primarily on TCP/IP networks to configure diskless workstations.BOOTP sends a UDP message with a subnetwork broadcast address and waits

for a reply from a server that gives it the IP address.

What is anonymous FTP and why would you use it ?Anonymous FTP enables users to connect to a host without using a valid login

and password. Usually, anonymous FTP uses a login called anonymous or guest,

with the password usually requesting the user's ID for tracking purposes only.Anonymous FTP is used to enable a large number of users to access files.


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How do Data Link layer addresses and Network addresses differ? Give adescription of each.Besides the names suggesting that addresses reside at different layers, otherdifferences do exist. Data Link layer addresses are assigned by the manufacturer

and identify the actual hardware device. A Network layer address is a logicaladdress assigned by the network administrator to identify a device running a

Network layer protocol, such as IP.

What are the differences or similarities, if any, between repeaters, hubs,

and concentrators ?First, they are all Physical layer devices. Repeaters regenerate and amplify thesignal traveling on the wire to extend the normal distance limitation of the signal.

A repeater can connect two network segments. A hub and a concentrator are the

same thing, with hub being the more common term used today. Hubs arerepeaters with 824 ports. When one machine attached to the hub sends

anything over the network, all the devices attached to the hub receive that signal.

Describe, in general terms, the reasons for implementing LANsegmentation.

It confines user traffic to a segment and addresses and solves distance limitation

problems. Segmentation also cuts down on the traffic generated by broadcastsand multicasts, and thereby increases performance. Because of the reduction of

the size of the segment, collisions and overall traffic also are reduced.

Which of the three switching methods is fastest, and why ?Cut-Through switching is the fastest method because the switches read only the

first six bytes of the frame before forwarding it.

What services do bridges and switches provide ?Bridges and switches can determine whether a frame is destined for the local


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network segment or needs to be forwarded to another network segment based

on the destination MAC address.

What are some of the advantages to using bridging and switching insteadof routing ?a) Increased overhead and latencyb) Reduced overhead and latency

c) Broadcast propagation

d) Lower equipment costsAnswer A is incorrect because it is a negative aspect of routing as compared to

switching. Answer B is correctbecause bridges and switches look only at

Data Link layer information, whereas routers must process all the logicaladdress information in the route tables. Answer C is incorrect becauseswitches do not have this effect. Answer D is incorrect because switches are now

very sophisticated and can cost as much as routers.

What would be the best network segmentation device if you wanted to

connect two dissimilar networks, such as Ethernet and Token-Ring ?a) A bridge or a switchb) A concentrator or a hub

c) A routerd) A gateway

Answer A is incorrect because bridges and switches cant perform protocol

translation. Answer B is incorrect because neither a concentrator nor a hub can

segment a network. Answer C is correct because routers can providetranslation between dissimilar protocols, among other things. Answer D is

incorrect because a gateway functions as a translator, not a segmentation

device.

Why is overhead or latency associated with routers? (Choose all thatapply.)a) Routers must work at layer 3, which is inherently slower.b) Routers must examine the frame header before passing it.


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c) Routers must hold a frame for a given period of time for security purposes.

d) Routers must translate the signal, but then the signal can cut through directly.Answer A is correctbecause resolving those addresses is more time

consuming. Answer B is correct because the router must examine and

consider the frame header detail before passing it, which slowsprocessing. Answers C and D are incorrect because they are simply not

accurate.

Which of the following represents Physical layer devices?a) Repeaters, bridges, and concentrators

b) Repeaters, hubs, and concentrators

c) Repeaters, routers, and bridgesd) Repeaters, routers, and switchesAnswer B is correctbecause repeaters, hubs, and concentrators comprise

the only combination that resides at the Physical layer. Answers A, C, and D

are combinations of devices that reside at different layers.

How do routers make routing decisions?a) They build tables and make their decisions based on those tables.b) They perform lookups and make their decisions dynamically with discovery.

c) They use hello packets to discover routes on the fly.d) They query NetBIOS cache for the appropriate paths.

Answer A is correctbecause routing decisions are made based on the

contents of routing tables. Answer B is incorrect because routers are incapable

of making decisions without tables already in place. Answer C is incorrectbecause hello packets are used to calculate routes when new routers are added

to a network. Answer D is incorrect because it is simply inaccurate.

Choose the devices that are used for Data Link layer segmentation.a) Concentrators and switchesb) Routers and bridges


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c) Bridges and switches

d) Bridges and hubsAnswer A is incorrect because concentrators reside at the Physical layer and

switches at the Data Link layer. Answer B is incorrect because routers are level 3

devices and bridges are level 2 devices. Answer C is correctbecause bridgesand switches reside at the Data Link layer. Answer D is incorrect because

bridges reside at the Data Link layer and hubs at the Physical layer.

What is an advantage of having a VLAN (Virtual LAN) ?a) Traffic control between VLANs is processor intensive.

b) Broadcasts of multicast traffic are contained within one VLAN.

c) Theyre more flexible because they enable device assignment only on a port-byportbasis.

d) With VLANs, users are not inherently isolated by group.

Answer A is incorrect because there is nothing more or less processor intensiveabout VLANs. Answer B is incorrect because there is no such thing as a

broadcast of multicast traffic; the words broadcast and multicast are mutually

exclusive.Answer C is correct because VLANs extend the flexibility of LANs

by enabling the port-by-port isolation of users and assignment to distinctVLANs if desired.Answer D is incorrect because VLANs by their definition

segment workgroups.

Which two characteristics describe Store and Forward switching ?a) The entire frame is copied into the buffer.b) The frame is forwarded based on the first six bytes.

c) It provides higher throughput.

d) It provides error checking.Answers A and D are correctbecause Store and Forward switching copies

the entire frame into the buffer before forwarding, which also provides for

error checking. Answers B and C are incorrect because they describe Cut-Through.


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Which two characteristics describe Cut-Through switching?a) The entire frame is copied into the buffer.

b) The frame is forwarded based on the first six bytes.c) It provides higher throughput.

d) It provides error checking.Answers B and C are correctbecause Cut-Through switching provides

forwarding based on what is contained in the first six bytes of the frame,which provides higher throughput. Answers A and D are incorrect because

they describe Store and Forward switching.

Name the Cisco proprietary protocol that allows VLANs to be managed

within domains.VTP (VLAN Trunking Protocol) allows multiple VLANs to be managed within a

single VTP domain.

Name the three VTP modes in which a switch can operate.VTP switches operate in one of three modes: server, client, or transparent.

Name the Cisco proprietary protocol used on Fast Ethernet VLAN trunklinks.ISL (Inter-Switch Link) protocol is used to encapsulate VLAN traffic over Fast

Ethernet trunk links.

At what layer of the OSI model do VLANs operate?VLANs operate at layer 2 of the OSI model.


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To allow Inter-VLAN communication, what does your router require?You need a router that has some kind of viable trunking connection, such as FastEthernet (ISL), and must be configured with subinterfaces.

Choose one method of decreasing broadcasts across a switched network.a) Set up an Intra-LAN.

b) Set up a workgroup banded by a server cluster.c) Set up a VLAN to isolate traffic.

d) Set up a firewall to isolate traffic.

Answers A and B are incorrect because they are simply false. Answer C iscorrectbecause each VLAN becomes its own broadcast domain. Answer D

is incorrect because a firewall is meant to shelter internal networks from intrusion

from the outside.

Choose two benefits of VLAN implementation.a)VLANs incorporate only one router per routed subnet.

b) VLANs control broadcasts.c) VLANs amplify broadcasts.

d) VLANs ease security restrictions.

e) VLANs provide increased network security.Answer A is incorrect because routers are not at all necessary for a VLAN to

operate.Answers B and E are correct because VLAN implementationcontrols broadcasts and provides isolation, therefore security. Answers C

and D are simply incorrect.

What is the purpose of a trunking protocol?a) To connect the backbone of a primary VLAN to the backbone of a secondary

VLAN

b) For one switch fabric to be integrated with another switch fabricc) For a VLAN on one switch to be linked to a VLAN on another switch

d) To enable multiple trunking protocols to communicateAnswers A is incorrect because it uses wrong terminology. Answer B is incorrect


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because switch fabric is a hardware-related component of a switch and belongs

to one switch only.Answer C is correct because trunking protocols allowmanagement of VLANs with similar or dissimilar trunking protocols.Answer

D is incorrect because a trunking protocol does not enable multiple trunking

protocols to communicate.

Choose the encapsulation protocol used on Fast Ethernet links.a) Cisco Switch Link

b) Dedicated Switch Linkc) Inter-Switch Link

d) VLAN Switch Link

Answer C is correctbecause Inter-Switch Link protocol is theencapsulation protocol used on Fast Ethernet links. Answers A, B, and D isincorrect because no such links exist.

At which layer of the OSI model does ISL function?a) Data Link layer

b) Network layer

c) Physical layerd) LLC Data Link sublayer

Answer A is correctbecause ISL functions at the Data Link layer of the OSImodel. Answers B and C are incorrect because ISL does not function at those

layers of the OSI model. Answer D is incorrect because the specific sublayer

does not have any distinction in this context.

Which method is used by VTP to convey VLAN configuration informationwithin its management domain?a) Through directed broadcastsb) Through LSAs local service advertisements

c) Through multicast advertisementsd) Through port flooding


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Answer C is correctbecause multicast advertisement convey configuration

information to all connected switches in the same managementdomain. Answers A, B, and D is incorrect because they do not convey

information within management domains.

In ATM LANE, what factor determines the type of trunking protocol used ?a) The link type

b) The encapsulation mode

c) The density of VLANsd) The ATM LANE Module type

Answer A is correct because the link type determines the type of trunking

protocol used.Answers B and C are incorrect because they are simply false.Answer D is incorrect because the ATM LANE Module is a hardware card anddoes not affect trunking protocols.

What is VTP designed to do ?a) It enables an administrator to manage VLANs across multiple trunk links.

b) nIt enables an administrator to manage VLANs across dissimilar trunking

protocols.c) It enables an administrator to merge the management duties of more than two

trunk links together.d)It is used to synchronize VTP advertisements across multiple trunk links.

Answer A is incorrect because trunk links do not address the aspect of

communication. Answer B is correctbecause VTP is designed to enable an

administrator to manage VLANs running dissimilar trunkingprotocols. Answer C is incorrect because a trunk link does not necessary entail

management duties on its own. Answer D is incorrect because it is simply false.

What is a limitation of Intra-VLAN traffic ?a) Communication is limited to VLANs directly connected to a router.B) Communication is limited to VLANs off the same switch backplane.


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C) Communication is limited to devices within the same VLAN.

d) Communication is limited to devices between VLANs.Answer A is incorrect because VLANs are connected for Inter-VLAN

communication. Answer B is incorrect because the backplane is where traffic is

actually switched, and it is a hardware component. Answer C is correctbecause that is the very definition of Intra-VLAN traffic. Answer D is incorrect

because VLANs cannot talk to each other without a router.

VTP (Virtual Trunking Protocol) exists at which layer and for what purpose ?A) Layer 2, to maintain VLAN configuration consistency

B) Layer 2, to maintain trunking protocol synchronization

C) Layer 2, to maintain domain synchronizationD) Layer 3, to maintain access listsAnswer A is correctbecause VTP operates at layer 2 and maintains VLAN

configuration consistency. Although the OSI layer is correct, answers B and C

are incorrect because the second portion of the answers is incorrect. Answer D isincorrect because VTP and switching do not operate at layer 3 and access lists

are maintained on routers.

What two basic steps are necessary to create access list filters ?The first step is to build the list at global configuration mode using the access-listcommand followed by an access list number signifying the type. The second step

is to apply the list to an interface by using the [protocol type] access-group

command followed by the access list number and parameters.

Identify the appropriate access list range values used to create accesslists.

IP standard access list = 199

IP extended access list = 100199IPX standard access list = 800899

IPX extended access list = 900999

IPX SAP filter = 10001099


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What is the purpose of a wildcard mask?To enable an administrator to apply an access list rule to a group of hosts or

subnets by masking off bits within an IP address, making the bit positions within

the mask variable.Name the access list keywords.

any = 0.0.0.0 255.255.255.255host = specific IP address of an end host (192.16.10.2 0.0.0.0)

How does the direction in which an access list is applied affect datagramprocessing?

Access lists applied to an interface in an inbound direction determine whether adatagram received on an interface will be forwarded or blocked. Access listsapplied to an interface in an outbound direction determine whether a datagram

already received will be forwarded out that interface.

What is the access list number range used to identify an IP standard

access list ?a) 0100b) 1100

c) 199d) 110

e) 101199

Answer C is correctbecause the correct value range to identify an IP

standard access list is 199. Answers A, B, D, and E are incorrect becausethey are not ranges used to identify an IP standard access list.

Which of the following represents the default wildcard mask value ?a)0.0.0.0

b) 255.255.255.255c) 0.0.255.255


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d) 255.255.255.0Answer A is correctbecause, if unspecified, the default mask used is0.0.0.0. Answers B and C are incorrect because neither are the default mask.

Answer D is incorrect because it is a regular mask, which is not used for wildcard

masking.

Write the command that would apply access list 100 to interface E0 in an

outbound direction. (Assume you are already at interface configurationmode of the Ethernet interface.)a) IP access-group 100 out

b) IP access-list 100 out

c) IP access-group 100 ind) IP access-group E0 out

Answer A is correct because IP access-group 100 out is the command that

would apply access list 100 to interface E0 in an outbound direction.Answers B, C, and D are simply incorrect.Which of the following commands creates a standard IP extended access

list that enables ping echo requests to be sent from any host on network

166.10.0.0 to network 155.10.0.0 ?a) Access-list 12 permit IP 166.10.0.0.0.0.255.255 host 155.10.0.0b) Access-list 120 permit ICMP 166.10.0.0 0.0.255.155 155.10.0.0 0.0.0.255 eq

echo

c) Access-list 120 permit 166.10.0.0.0.0.255.255 host 155.10.0.0

d) Access-list 120 permit ICMP 166.10.0.0 0.0.255.255 155.10.0.0 0.0.255.255 eqecho

Answer A is incorrect because the access list number is not an extended list

number. Also, the protocol type is IP not ICMP, and the destination is specifyingthe host keyword but using a subnet value instead, which is invalid. Answer B is

incorrect because it uses an incorrect inverse mask for the destination network.

Answer C is incorrect because it does not specify the protocol after the permitstatement and also is using the host keyword with the destination

network. Answer D is correctbecause it uses a valid access list number andsyntax to forward ICMP echo requests.


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Write the command to view all access lists created on your routerregardless of protocol.a) show access-listsb) show ip access-lists

c) show ipx interfacesd) show ipx servers

Answer A is correctbecause show access-lists enables you to view all

access lists created on your router regardless of protocol. Answers B, C,and D are incorrect because these commands do not enable you to perform that

specific function.

Which of the following best describes the function of the following accesslist line ?

Access-list 87 permit 145.19.2.1 0.0.0.0 155.6.0.0 0.0.255.255

a) Any host on subnet 155.6.0.0 can access host 145.19.2.1.b) it is an IPX standard access list allowing host 145.19.2.1 to access any host on

subnet 155.6.0.0.

c) It is an extended IP access list allowing hosts on network 145.19.0.0 to accesshosts on network 145.19.0.0, which can access host 155.6.255.255.

d) It is an IP standard access list enabling host 145.19.2.1 to access any host onsubnet 155.6.0.0.

Answers A and C are incorrect because they do not state the actions of this

access list correctly. Answer B is incorrect because this is not an IPX standard

list.Answer D is correctbecause it correctly describes the access listbehavior.

Which of the following commands applies IPX SAP filter 1010 to aninterface in the outbound direction?a) IPX access-group 1010 outb) IPX output-sap-filter 1010


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c) IPX output sap-filter 1010

d) IPX-sap-filter 1010 outAnswer A is incorrect because it is the syntax used to define a standard or

extended list.Answer B is correctbecause it uses the correct syntax.

Answer C is incorrect because it is missing the hyphen between the output andsap commands. Answer D is incorrect because it is a completely invalid

command.

Which command can you use to display a list of access list filters

configured on your router for IP only?a) show IP access-lists

b) show access-listsc) show IPX interfacesd) show IPX servers

Answer A is correctbecause show IP access-lists enables you to display a

list of access list filters configured on your router for IP only. Answers B, C,and D are incorrect because these commands do not enable that specific

function.

Write the command to bind IPX extended access list 901 to interface serial0 on an inbound direction.a) IPX access-group 901 in

b) IPX access-group 901 S0 out

c) IPX access-group 910 in

d) IPX access-group 901 outAnswer A is correctbecause IPX access-group 901 in is the command that

will bind the IPX extended access list 901 to interface serial 0 on an

inbound direction. Answers B, C, and D are incorrect because they are simplyfalse.

Which two of the following commands will enable Telnet traffic from all


26/26

hosts on network 166.10.0.0 to be forwarded to the Telnet server137.2.10.1?a) Access-list 110 permit TCP 166.10.0.0 0.0.255.255 host 137.2.10.1 eq Telnet

b) Access-list 99 permit TCP 166.10.0.0 0.0.255.255 137.2.10.1 0.0.0.0. eq 23

c) Access-list 110 permit TCP 166.10.0.0 0.0.255.255 137.2.10.1 0.0.0.0 eq 23d) Access-list 110 permit IP 166.10.0.0 0.0.255.255 137.2.10.1 0.0.0.0. eq 23

Answers A and C are correct. The only difference between the two is thatAnswer A uses the host keyword and the Telnet keyword instead of a port

number. Answer B is incorrect because the access list number is 99, which isused for standard lists. Answer D is incorrect because it uses IP instead of TCP

after the permit statement.

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