CompTIA Network+ Question B-7

A company wants to create highly available datacenters. Which of the following will allow the company to continue to maintain an Internet presence at all sites in the event that a WAN circuit at one site goes down?

A. Load balancer
B. VRRP
C. OSPF
D. BGP

Correct Answer: D

Explanation:
A collection of networks that fall within the same administrative domain is called an autonomous system (AS). In this question, each datacenter will be an autonomous system.
The routers within an AS use an interior gateway protocol, such as the Routing Information Protocol (RIP) or the Open Shortest Path First (OSPF) protocol, to exchange routing information among themselves. At the edges of an AS are routers that communicate with the other AS’s on the Internet, using an exterior gateway protocol such as the Border Gateway Protocol (BGP).
If a WAN link goes down, BGP will route data through another WAN link if redundant WAN links are available.

CompTIA Network+ Question A-75

A network engineer is designing a new network for a remote site. The remote site consists of ten desktop computers, ten VoIP phones, and two network printers. In addition, two of the desktop computers at the remote site will be used by managers who should be on a separate network from the other eight computers. Which of the following represents the BEST configuration for the remote site?

A. One router connected to one 24-port switch configured with three VLANS: one for the manager’s computers and printer, one for the other computers and printer, and one for the VoIP phones
B. Two routers with each router connected to a 12-port switch, with a firewall connected to the switch connected to the manager’s desktop computers, VoIP phones, and printer
C. One router connected to one 12-port switch configured for the manager’s computers, phones, and printer, and one 12-port switch configured for the other computers, VoIP phones, and printer
D. One router connected to one 24-port switch configured with two VLANS: one for the manager’s computers, VoIP phones, and printer, and one for the other computers, VoIP phones, and printer

Correct Answer: A

CompTIA Network+ Question A-73

A network administrator notices that the border router is having high network capacity loads during non-working hours which is causing web services outages. Which of the following is the MOST likely cause?

A. Evil twin
B. Session hijacking
C. Distributed DoS
D. ARP cache poisoning

Correct Answer: C

CompTIA Network+ Question A-69

A technician needs to limit the amount of broadcast traffic on a network and allow different segments to communicate with each other. Which of the following options would satisfy these requirements?

A. Add a router and enable OSPF.
B. Add a layer 3 switch and create a VLAN.
C. Add a bridge between two switches.
D. Add a firewall and implement proper ACL.

Correct Answer: B

Explanation:
We can limit the amount of broadcast traffic on a switched network by dividing the computers into logical network segments called VLANs.
A virtual local area network (VLAN) is a logical group of computers that appear to be on the same LAN even if they are on separate IP subnets. These logical subnets are configured in the network switches. Each VLAN is a broadcast domain meaning that only computers within the same VLAN will receive broadcast traffic.
To allow different segments (VLAN) to communicate with each other, a router is required to establish a connection between the systems. We can use a network router to route between the VLANs or we can use a ‘Layer 3’ switch. Unlike layer 2 switches that can only read the contents of the data-link layer protocol header in the packets they process, layer 3 switches can read the (IP) addresses in the network layer protocol header as well.

CompTIA Network+ Question A-58

A technician is diagnosing an issue with a new T1 connection. The router is configured, the cable is connected, but the T1 is down. To verify the configuration of the router, which of the following tools should the technician use?

A. Loopback adapter
B. Cable tester
C. Tone generator
D. Multimeter

Correct Answer: A

CompTIA Network+ Question A-46

A technician has finished configuring AAA on a new network device. However, the technician is unable to log into the device with LDAP credentials but is able to do so with a local user account. Which of the following is the MOST likely reason for the problem?

A. Username is misspelled is the device configuration file
B. IDS is blocking RADIUS
C. Shared secret key is mismatched
D. Group policy has not propagated to the device

Correct Answer: C

Explanation:
AAA through RADIUS uses a Server Secret Key (a shared secret key). A secret key mismatch could cause login problems.
Authentication, authorization, and accounting (AAA) allows a network to have a single repository of user credentials. A network administrator can then, for example, supply the same credentials to log in to various network devices (for example, routers and switches). RADIUS and TACACS+ are protocols commonly used to communicate with an AAA server.

CompTIA Network+ Question A-42

A network technician has configured a point-to-point interface on a router, however, once the fiber optic cables have been run, the interface will not come up. The technician has cleaned the fiber connectors and used an optical power meter to confirm that light is passing in both directions without excessive loss. Which of the following is the MOST likely cause?

A. Distance limitation
B. Wavelength mismatch
C. cross-talk
D. EMI
E. Macro bend

Correct Answer: B

CompTIA Network+ Question A-38

A technician add memory to a router, but that memory is never recognized by the router. The router is then powered down, and the technician relocates all of the memory to different modules. On startup, the router does not boot and displays memory errors. Which of the following is MOST likely the cause?

A. VTP
B. Driver update
C. ESD
D. Halon particles

Correct Answer: B

CompTIA Network+ Question A-32

A user is unable to connect to a server in another building. A technician is troubleshooting the issue and determines the following:
1) Client PC 1 has an IP address if 192.168.10.25/25
2) PC 1 can successfully ping its gateway of 192.168.10.1/25 which is an interface of router A
3)Server A is named ‘BLDGBFILESRVR01’ and has an IP address of 192.168.10.145/25
4) PC 2 with an IP address of 192.168.10.200/25 can successfully ping server A
However, when PC 1 pings server A, it receives a destination host unreachable responds. Which of the following is the MOST likely cause?

A. Link from touter A to PC 1 are on different subnets
B. Link from router A to server A is down
C. Link from PC 1 to router A has duplex issues
D. Link from server A top PC 2 is down

Correct Answer: B

Explanation:
PC 1 cannot connect to Server A. PC 1 and Server A are on different subnets that are connected by Router A. PC 1 can connect to Router A; therefore there is no problem with the link or IP address configuration between PC 1 and Router A.
PC 2, which is on the same subnet as Server A, can connect to Server A; therefore Server A is up.
As PC 1 can connect to Router A but cannot connect to Server A, and Server A is up; the problem must be the connection (link) between Router A and Server A.

CompTIA Network+ Question A-23

Peter, a network technician, is setting up a DHCP server on a LAN segment. Which of the following options should Peter configure in the DHCP scope, in order to allow hosts on that LAN segment using dynamic IP addresses, to be able to access the Internet and internal company servers? (Select THREE).

A. Default gateway
B. Subnet mask
C. Reservations
D. TFTP server
E. Lease expiration time of 1 day
F. DNS servers
G. Bootp

Correct Answer: ABF

Explanation:
The question states that the client computers need to access the Internet as well as internal company servers. To access the Internet, the client computers need to be configured with an IP address with a subnet mask (answer B) and the address of the router that connects the company network to the Internet. This is known as the ‘default gateway’ (answer A).
To be able to resolve web page URLs to web server IP addresses, the client computers need to be configured with the address of a DNS server (answer F).