A network engineer needs to set up a topology that will not fail if there is an outage on a
single piece of the topology. However, the computers need to wait to talk on the network to
avoid congestions. Which of the following topologies would the engineer implement?
Answer : C
Explanation: Token Ring networks are quite rare today. Token Ring networks use the ring topology. Despite being called a Ring topology, the ring is logical and the physical network structure often forms a star topology with all computers on the network connecting to a central multistation access unit (MAU). The MAU implements the logical ring by transmitting signals to each node in turn and waiting for the node to send them back before it transmits to the next node. Therefore, although the cables are physically connected in a star, the data path takes the form of a ring. If any computer or network cable fails in a token ring network, the remainder of the network remains functional. The MAU has the intelligence to isolate the failed segment. To ensure that the computers need to wait to talk on the network to avoid congestions, a Token Ring network uses a token. The token continually passes around the network until a computer needs to send data. The computer then takes the token and transmits the data beforereleasing the token. Only a computer in possession of the token can transmit data onto the network.
A host has been assigned the address 169.254.0.1. This is an example of which of the
following address types?
Answer : A
Explanation: APIPA stands for Automatic Private IP Addressing and is a feature of Windows operating systems. When a client computer is configured to use automatic addressing (DHCP), APIPA assigns a class B IP address from 169.254.0.0 to 169.254.255.255 to the client when a DHCP server is unavailable. When a client computer configured to use DHCP boots up, it first looks for a DHCP server to provide the client with IP address and subnet mask. If the client is unable to contact a DHCP server, it uses APIPA to automatically configure itself with an IP address from a range that has been reserved especially for Microsoft. The client also configures itself with a default class Bsubnet mask of 255.255.0.0. The client will use the self-configured IP address until a DHCP server becomes available.
The network install is failing redundancy testing at the MDF. The traffic being transported is
a mixture of multicast and unicast signals. Which of the following would BEST handle the
rerouting caused by the disruption of service?
Answer : A
Explanation: The question states that the traffic being transported is a mixture of multicast and unicast signals. There are three basic types of network transmissions: broadcasts, which are packets transmitted to every node on the network; unicasts,which are packets transmitted to just one node; and multicasts, which are packets transmitted to a group of nodes. Multicast is a layer 3 feature of IPv4 & IPv6. Therefore, we would need a layer 3 switch (or a router) to reroute the traffic. Unlike layer 2switches 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.
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?
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 ASs on the Internet, using an exterior gateway protocol such as the Border Gateway Protocol (BGP). If a WAN link goes down, BGP will route datathrough another WAN link if redundant WAN links are available.
A technician is connecting a NAS device to an Ethernet network. Which of the following
technologies will be used to encapsulate the frames?
Answer : C
Explanation: A NAS or a SAN will use either iSCSI or Fiber Channel. In this question, the NAS is connected to an Ethernet network. Therefore, iSCSI will most likely be used (Fiber Channel over Ethernet (FCoE) can be used but is less common). ISCSI means Internet SCSI. ISCSI uses TCP (Transmission Control Protocol) which enables it to be used over TCP/IP networks such as Ethernet. For Fiber channel,a separate Fiber Channel network would be required unless FCoE is used.
Which of the following is used to define how much bandwidth can be used by various
protocols on the network?
Answer : A
Explanation: If a network connection becomes saturated to the point where there is a significant level of contention, network latency can rise substantially. Traffic shaping is used to control the bandwidth used by network traffic. In a corporate environment, business-related traffic may be given priority over other traffic. Traffic can be prioritized based on the ports used by the application sending the traffic. Delayed traffic is stored in a buffer until the higher priority traffic has been sent.
Corporate headquarters provided your office a portion of their class B subnet to use at a
new office location. Allocate the minimum number of addresses (using CIDR notation)
needed to accommodate each department.
Explanation: An IPv4 address consists of 32 bits. The first x number of bits in the address is the network address and the remaining bits are used for the host addresses. The subnet mask defines howmany bits form the network address and from that, we can calculate how many bits are used for the host addresses. The formula to calculate the number of hosts in a subnet is 2n - 2. The "n" in the host's formula represents the number of bits used for host addressing.If we apply the formula (22 2), we can determine that the following subnets should be configured: Sales network /26 This will provide up to 62 usable IP addresses (64-2 for subnet and broadcast IP) HR network - /27 This will provide for up to 30usable IPs (32-2) IT - /28 This will provide for up to 14 usable IPs (16-2) Finance - /26 Note that a /27 is 32 IP addresses but 2 of those are reserved for the network and broadcast IPs and cant be used for hosts. Marketing - /28 If we add up howmany IP blocks are used that is 64+32+16+64+16=192. A /24 contains 256 IP addresses, so 256-192=64. So the last unused box should be a /26, which equates to 64 addresses
Joe, a network technician, is setting up a DHCP server on a LAN segment. Which of the
following options should Joe 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).
Answer : A,B,F
Explanation: The question statesthat 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 thecompany 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).
Which of the following would be used in an IP-based video conferencing deployment?
Answer : D,E
Explanation: The term "codec" is a concatenation of "encoder" and "decoder. In video conferencing, a codec is software (or can be hardware) that compresses (encodes) raw video data before it is transmitted overthe network. A codec on the receiving video conferencing device will then decompress (decode) the video signal for display on the conferencing display. The Session Initiation Protocol (SIP) is a protocol for initiating an interactive user session that involves multimedia elements such as voice, chat, gaming, or in this case video.
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
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. Toallow 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.
A technician, Joe, has been tasked with assigning two IP addresses to WAN interfaces on
connected routers. In order to conserve address space, which of the following subnet
masks should Joe use for this subnet?
Answer : E
Explanation: An IPv4 addressconsists of 32 bits. The first x number of bits in the address is the network address and the remaining bits are used for the host addresses. The subnet mask defines how many bits form the network address and from that, we can calculate how many bits are used for the host addresses. In this question, the /30 subnet mask dictates that the first 30 bits of the IP address are used for network addressing and the remaining 2 bits are used for host addressing. The formula to calculate the number of hosts in a subnet is 2n - 2. The "n" in the host's formula represents the number of bits used for host addressing. If we apply the formula (22 2), a /30 subnet mask will provide 2 IP addresses.
Which of the following network infrastructure implementations would be used to support
files being transferred between Bluetooth-enabled smartphones?
Answer : A
Explanation: PAN stands for Personal Area Network. It is a network of devices in the area of a person typically within a range of 10 meters and commonly using a wirelesstechnology such as Bluetooth or IR (Infra-Red).
A SQL server needs several terabytes of disk space available to do an uncompressed
backup of a database. Which of the following devices would be the MOST cost efficient to
use for this backup?
Answer : C
Explanation: A NAS is a Network Attached Storage device; typically a bunch of cheap hard disks, usually arranged in a Raid and consisting of either SAS (serial attached SCSI) or Sata disks just like the ones in most desktops. A NAS is essentially a file server that connects to an Ethernet network and is configured with a TCP/IP address. A NAS supports Windows networking and works at the file level as opposedto a SAN (Storage Area Network) which works at the block level when dealing with data. You can access file shares on a NAS in the same way that you would access file shares on a file server. A NAS is a much cheaper option than a SAN.
Which of the following is MOST likely to use an RJ-11 connector to connect a computer to
an ISP using a POTS line?
Answer : C
Explanation: Before ADSL broadband connections became the standard for Internet connections, computers used analog modems to connect to the Internet. By todays standards, analog modems are very slow typically offering a maximum bandwidth of 56Kbps. An analog modem (modulator/demodulator) converts (modulates) a digital signal from a computerto an analog signal to be transmitted over a standard (POTS) phone line. The modem then converts (demodulates) the incoming analog signal to digital data to be used by the computer. An analog modem uses an RJ-11 connector to connect to a phone line (POTS)in the same way a phone does.
A technician just completed a new external website and setup access rules in the firewall.
After some testing, only users outside the internal network can reach the site. The website
responds to a ping from the internal network and resolves the proper public address. Which
of the following could the technician do to fix this issue while causing internal users to route
to the website using an internal address?
Answer : B
Explanation: Split horizon DNS (also known as Split Brain DNS) is a mechanism for DNS servers to supply different DNS query results depending on the source of the request. This can be done by hardware-basedseparation but is most commonly done in software. In this question, we want external users to be able to access the website by using a public IP address. To do this, we would have an external facing DNS server hosting a DNS zone for the website domain. Forthe internal users, we would have an internal facing DNS server hosting a DNS zone for the website domain. The external DNS zone will resolve the website URL to an external public IP address. The internal DNS server will resolve the website URL to an internal private IP address.