CCNA Chapter 5

Match the seven fields of an Ethernet frame to their respective contents. Beginning of frame - Field 1

Preamble

What happens to runt frames received by a Cisco Ethernet switch?

The frame is dropped.

A network administrator is connecting two modern switches using a straight-through cable. The switches are new and have never been configured. Which three statements are correct about the final result of the connection?

The link between the switches will work at the fastest speed that is supported by both switches. The link between switches will work as full-duplex. The auto-MDIX feature will configure the interfaces eliminating the need for a crossover cable.

What statement describes a characteristic of MAC addresses?

They must be globally unique.

How does adding an Ethernet line card affect the form factor of a switch?

by expanding the port density

Fill in the blank. ARP _____________ is a technique that is used to send fake ARP messages to other hosts in the LAN. The aim is to associate IP addresses to the wrong MAC addresses.

spoofing

Which switching method uses the CRC value in a frame?

store-and-forward

Open the PT Activity. Perform the tasks in the activity instruction and then answer the question. What destination address will PC1 include in the destination address field of the Ethernet frame that it sends to PC2?

0030.a3e5.0401

Match the seven fields of an Ethernet frame to their respective contents. Field 6

Encapsulated Data

What are two features of ARP?

If a host is ready to send a packet to a local destination device and it has the IP address but not the MAC address of the destination, it generates an ARP broadcast. If a device receiving an ARP request has the destination IPv4 address, it responds with an ARP reply.

Refer to the exhibit. The exhibit shows a small switched network and the contents of the MAC address table of the switch. PC1 has sent a frame addressed to PC3. What will the switch do with the frame?

The switch will forward the frame to all ports except port 4.

Which statement describes the treatment of ARP requests on the local link?

They are received and processed by every device on the local network.

What is the Layer 2 multicast MAC address that corresponds to the Layer 3 IPv4 multicast address 224.139.34.56?

01-00-5E-0B-22-38

What statement illustrates a drawback of the CSMA/CD access method?

Collisions can decrease network performance.

Which two statements are correct about MAC and IP addresses during data transmission if NAT is not involved?

Destination and source MAC addresses have local significance and change every time a frame goes from one LAN to another. Destination IP addresses in a packet header remain constant along the entire path to a target host.

Which destination address is used in an ARP request frame?

FFFF.FFFF.FFFF

Match the seven fields of an Ethernet frame to their respective contents. End of frame - Field 7

Frame Check Sequence

What statement describes Ethernet?

It defines the most common LAN type in the world.

What is a characteristic of a contention-based access method?

It is a nondeterministic method.

A host is trying to send a packet to a device on a remote LAN segment, but there are currently no mappings in its ARP cache. How will the device obtain a destination MAC address?

It will send an ARP request for the MAC address of the default gateway.

The ARP table in a switch maps which two types of address together?

Layer 3 address to a Layer 2 address

Refer to the exhibit. PC1 issues an ARP request because it needs to send a packet to PC2. In this scenario, what will happen next?

PC2 will send an ARP reply with its MAC address.

Which statement is true about MAC addresses?

The first three bytes are used by the vendor assigned OUI.

What is auto-MDIX?

a feature that detects Ethernet cable type

Match the characteristic to the forwarding method. Cut-Through

low latency may forward runt frames begins forwarding when the destination address is received

Refer to the exhibit. The switches are in their default configuration. Host A needs to communicate with host D, but host A does not have the MAC address for its default gateway. Which network hosts will receive the ARP request sent by host A?

only hosts B, C, and router R1

What addressing information is recorded by a switch to build its MAC address table?

the source Layer 2 address of incoming frames

When would a switch record multiple entries for a single switch port in its MAC address table?

when another switch is connected to the switch port

What are the two sizes (minimum and maximum) of an Ethernet frame?

64 bytes 1518 bytes

Which two statements describe a fixed configuration Ethernet switch?

A fixed configuration switch may be stackable. The number of ports on the switch cannot be increased.

Match the seven fields of an Ethernet frame to their respective contents. Field 3

Destination MAC Address

Refer to the exhibit. A switch with a default configuration connects four hosts. The ARP table for host A is shown. What happens when host A wants to send an IP packet to host D?

Host A sends out a broadcast of FF:FF:FF:FF:FF:FF. Every other host connected to the switch receives the broadcast and host D responds with its MAC address.

Fill in the blank. A collision fragment, also known as a _____________ frame, is a frame of fewer than 64 bytes in length.

RUNT

Match the seven fields of an Ethernet frame to their respective contents. Field 5

Length/Type

Which two statements describe features or functions of the logical link control sublayer in Ethernet standards?

Logical link control is implemented in software. The data link layer uses LLC to communicate with the upper layers of the protocol suite.

Which address or combination of addresses does a Layer 3 switch use to make forwarding decisions?

MAC and IP addresses

What are two potential network problems that can result from ARP operation?

On large networks with low bandwidth, multiple ARP broadcasts could cause data communication delays. Network attackers could manipulate MAC address and IP address mappings in ARP messages with the intent of intercepting network traffic.

Match the seven fields of an Ethernet frame to their respective contents. Field 4

Source MAC Address

Match the seven fields of an Ethernet frame to their respective contents. Field 2

Start Frame Delimiter

True or False? When a device is sending data to another device on a remote network, the Ethernet frame is sent to the MAC address of the default gateway.

True

A network administrator issues the following commands on a Layer 3 switch: DLS1(config)# interface f0/3 DLS1(config-if)# no switchport DLS1(config-if)# ip address 172.16.0.1 255.255.255.0 DLS1(config-if)# no shutdown DLS1(config-if)# end What is the administrator configuring?

a routed port

Match the characteristic to the forwarding method. Store-and-Forward

always stores the entire frame checks the CRC before forwarding checks the frame length before forwarding

What is the purpose of the preamble in an Ethernet frame?

is used for timing synchronization

Fill in the blank. On a Cisco switch, _____________ memory buffering is used to buffer frames in queues linked to specific incoming and outgoing ports.

port-based

A Layer 2 switch is used to switch incoming frames from a 1000BASE-T port to a port connected to a 100Base-T network. Which method of memory buffering would work best for this task?

shared memory buffering