CCNA 2 Chapter 4 v6 Exam Answers

Match the borderless switched network guideline description to the principle. (Not all options are used.)

Which network device can serve as a boundary to divide a Layer 2 broadcast domain?

Layer 1 and 2 devices (LAN switch and Ethernet hub) and access point devices do not filter MAC broadcast frames. Only a Layer 3 device, such as a router, can divide a Layer 2 broadcast domain.

What are two advantages of modular switches over fixed-configuration switches? (Choose two.)

Fixed-configuration switches, although lower in price, have a designated number of ports and no ability to add ports. They also typically provide fewer high-speed ports. In order to scale switching on a network that consists of fixed-configuration switches, more switches need to be purchased. This increases the number of power outlets that need to be used. Modular switches can be scaled simply by purchasing additional line cards. Bandwidth aggregation is also easier, because the backplane of the chassis can provide the bandwidth that is needed for the switch port line cards.

What is one function of a Layer 2 switch?

A switch builds a MAC address table of MAC addresses and associated port numbers by examining the source MAC address found in inbound frames. To forward a frame onward, the switch examines the destination MAC address, looks in the MAC address for a port number associated with that destination MAC address, and sends it to the specific port. If the destination MAC address is not in the table, the switch forwards the frame out all ports except the inbound port that originated the frame.

What does the term “port density” represent for an Ethernet switch?

The term port density represents the number of ports available in a switch. A one rack unit access switch can have up to 48 ports. Larger switches may support hundreds of ports.

A local law firm is redesigning the company network so that all 20 employees can be connected to a LAN and to the Internet. The law firm would prefer a low cost and easy solution for the project. What type of switch should be selected?

By looking at the graphic in 1.1.2.2 #2 and #3 and comparing those photos to the graphics used in the Cisco switch design model shown in 1.1.1.5 #2, you can see that the smaller rack unit fixed configuration switch is used as an access layer switch. The modular configuration switch would be used at the distribution and core layers.

A small publishing company has a network design such that when a broadcast is sent on the LAN, 200 devices receive the transmitted broadcast. How can the network administrator reduce the number of devices that receive broadcast traffic?

By dividing the one big network into two smaller network, the network administrator has created two smaller broadcast domains. When a broadcast is sent on the network now, the broadcast will only be sent to the devices on the same Ethernet LAN. The other LAN will not receive the broadcast.

Which solution would help a college alleviate network congestion due to collisions?

Switches provide microsegmentation so that one device does not compete for the same Ethernet network bandwidth with another network device, thus practically eliminating collisions. A high port density switch provides very fast connectivity for many devices.

What two criteria are used by a Cisco LAN switch to decide how to forward Ethernet frames? (Choose two.)

Cisco LAN switches use the MAC address table to make decisions of traffic forwarding. The decisions are based on the ingress port and the destination MAC address of the frame. The ingress port information is important because it carries the VLAN to which the port belongs.

What is the destination address in the header of a broadcast frame?

In a Layer 2 broadcast frame, the destination MAC address (contained in the frame header) is set to all binary ones, therefore, the format of FF-FF-FF-FF-FF-FF. The binary format of 11 in hexadecimal is 00010001. 255.255.255.255 and 0.0.0.0 are IP addresses.

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Match the functions to the corresponding layers. (Not all options are used.)

Which statement describes a result after multiple Cisco LAN switches are interconnected?

In Cisco LAN switches, the microsegmentation makes it possible for each port to represent a separate segment and thus each switch port represents a separate collision domain. This fact will not change when multiple switches are interconnected. However, LAN switches do not filter broadcast frames. A broadcast frame is flooded to all ports. Interconnected switches form one big broadcast domain.

Which type of address does a switch use to build the MAC address table?

When a switch receives a frame with a source MAC address that is not in the MAC address table, the switch will add that MAC address to the table and map that address to a specific port. Switches do not use IP addressing in the MAC address table.

A network designer must provide a rationale to a customer for a design which will move an enterprise from a flat network topology to a hierarchical network topology. Which two features of the hierarchical design make it the better choice? (Choose two.)

A hierarchical design for switches helps network administrators when planning and deploying a network expansion, performing fault isolation when a problem occurs, and providing resiliency when traffic levels are high. A good hierarchical design has redundancy when it can be afforded so that one switch does not cause all networks to be down.

Which two previously independent technologies should a network administrator attempt to combine after choosing to upgrade to a converged network infrastructure? (Choose two.)

A converged network provides a single infrastructure that combines voice, video, and data. Analog phones, user data, and point-to-point video traffic are all contained within the single network infrastructure of a converged network.

Match the forwarding characteristic to its type. (Not all options are used.)

Which network device can be used to eliminate collisions on an Ethernet network?

A switch provides microsegmentation so that no other device competes for the same Ethernet network bandwidth.

What is a definition of a two-tier LAN network design?

Maintaining three separate network tiers is not always required or cost-efficient. All network designs require an access layer, but a two-tier design can collapse the distribution and core layers into one layer to serve the needs of a small location with few users.

Refer to the exhibit. How many broadcast domains are displayed?

A router defines a broadcast boundary, so every link between two routers is a broadcast domain. In the exhibit, 4 links between routers make 4 broadcast domains. Also, each LAN that is connected to a router is a broadcast domain. The 4 LANs in the exhibit result in 4 more broadcast domains, so there are 8 broadcast domains in all.

Refer to the exhibit. How is a frame sent from PCA forwarded to PCC if the MAC address table on switch SW1 is empty?

When a switch powers on, the MAC address table is empty. The switch builds the MAC address table by examining the source MAC address of incoming frames. The switch forwards based on the destination MAC address found in the frame header. If a switch has no entries in the MAC address table or if the destination MAC address is not in the switch table, the switch will forward the frame out all ports except the port that brought the frame into the switch.

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What is a collapsed core in a network design?

A collapsed core design is appropriate for a small, single building business. This type of design uses two layers (the collapsed core and distribution layers consolidated into one layer and the access layer). Larger businesses use the traditional three-tier switch design model.

Fill in the blank.
A __ network is one that uses the same infrastructure to carry voice, data, and video signals.

Refer to the exhibit. Consider that the main power has just been restored. PC3 issues a broadcast IPv4 DHCP request. To which port will SW1 forward this request?​

What are two reasons a network administrator would segment a network with a Layer 2 switch? (Choose two.)

A switch has the ability of creating temporary point-to-point connections between the directly-attached transmitting and receiving network devices. The two devices have full-bandwidth full-duplex connectivity during the transmission.

What is a basic function of the Cisco Borderless Architecture distribution layer?

One of the basic functions of the distribution layer of the Cisco Borderless Architecture is to perform routing between different VLANs. Acting as a backbone and aggregating campus blocks are functions of the core layer. Providing access to end user devices is a function of the access layer.