Chapter 5 Test
27. What statement describes a characteristic of MAC addresses? They must be globally unique. They are only routable within the private network. They are added as part of a Layer 3 PDU. They have a 32-bit binary value.
They must be globally unique.*
15 When would a switch record multiple entries for a single switch port in its MAC address table? when the switch is configured for Layer 3 switching when another switch is connected to the switch port when a router is connected to the switch port when multiple ARP broadcasts have been forwarded
when another switch is connected to the switch port*
14 What statement illustrates a drawback of the CSMA/CD access method? Collisions can decrease network performance. Deterministic media access protocols slow network performance. CSMA/CD LAN technologies are only available at slower speeds than other LAN technologies.
Collisions can decrease network performance.*
7 Which two statements are correct about MAC and IP addresses during data transmission if NAT is not involved? (Choose two.) Destination MAC addresses will never change in a frame that goes across seven routers. A packet that has crossed four routers has changed the destination IP address four times. 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. Every time a frame is encapsulated with a new destination MAC address, a new destination IP address is needed.
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.*
28. Which destination address is used in an ARP request frame? 0.0.0.0 255.255.255.255 FFFF.FFFF.FFFF 127.0.0.1 01-00-5E-00-AA-23
FFFF.FFFF.FFFF*
30. Which switching method uses the CRC value in a frame? cut-through fast-forward fragment-free store-and-forward
store-and-forward*
38. 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
10 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? level 1 cache buffering shared memory buffering fixed configuration buffering port-based buffering
shared memory buffering*
39. 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
21 Fill in the blank. The binary number 0000 1010 can be expressed as _________ in hexadecimal.
"A"
16 Which two statements describe a fixed configuration Ethernet switch? (Choose two.) An SVI cannot be configured on the switch. A fixed configuration switch may be stackable. The number of ports on the switch cannot be increased. The port density of the switch is determined by the Cisco IOS. The switch cannot be configured with multiple VLANs.
A fixed configuration switch may be stackable.* The number of ports on the switch cannot be increased.*
8 What is the Layer 2 multicast MAC address that corresponds to the Layer 3 IPv4 multicast address 224.139.34.56? FE-80-00-0B-22-38 01-00-5E-0B-22-38 FF-FF-FF-0B-22-38 00-00-00-0B-22-38 01-5E-00-0B-22-38
01-00-5E-0B-22-38*
25. What are the two sizes (minimum and maximum) of an Ethernet frame? (Choose two.) 56 bytes 64 bytes 128 bytes 1024 bytes 1518 bytes
1518 bytes* 64 bytes*
22 What are two features of ARP? (Choose two.) 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. An ARP request is sent to all devices on the Ethernet LAN and contains the IP address of the destination host and its multicast MAC address. When a host is encapsulating a packet into a frame, it refers to the MAC address table to determine the mapping of IP addresses to MAC addresses. If a device receiving an ARP request has the destination IPv4 address, it responds with an ARP reply.
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.*
26. What statement describes Ethernet? It defines the most common LAN type in the world. It is the required Layer 1 and 2 standard for Internet communication. It defines a standard model used to describe how networking works. It connects multiple sites such as routers located in different countries.
It defines the most common LAN type in the world.*
13 What is a characteristic of a contention-based access method? It processes more overhead than the controlled access methods do. It scales very well under heavy media use. It is a nondeterministic method. It has mechanisms to track the turns to access the media.
It is a nondeterministic method.*
2 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 a request to the DNS server for the destination MAC address. It will send an ARP request for the MAC address of the destination device. It will send the frame and use its own MAC address as the destination. It will send the frame with a broadcast MAC address. It will send an ARP request for the MAC address of the default gateway.
It will send an ARP request for the MAC address of the default gateway.*
33. The ARP table in a switch maps which two types of address together? Layer 3 address to a Layer 2 address Layer 3 address to a Layer 4 address Layer 4 address to a Layer 2 address Layer 2 address to a Layer 4 address
Layer 3 address to a Layer 2 address*
17 Which two statements describe features or functions of the logical link control sublayer in Ethernet standards? (Choose two.) Logical link control is implemented in software. The LLC sublayer interacts directly with the NIC driver software. The data link layer uses LLC to communicate with the upper layers of the protocol suite. The LLC sublayer is responsible for the placement and retrieval of frames on and off the media. Logical link control is specified in the IEEE 802.3 standard.
Logical link control is implemented in software.* The data link layer uses LLC to communicate with the upper layers of the protocol suite.*
3 Which address or combination of addresses does a Layer 3 switch use to make forwarding decisions? MAC and IP addresses MAC address only MAC and port addresses port address only IP address only
MAC and IP addresses*
4 What are two potential network problems that can result from ARP operation? (Choose two.) Multiple ARP replies result in the switch MAC address table containing entries that match the MAC addresses of hosts that are connected to the relevant switch port. 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. Manually configuring static ARP associations could facilitate ARP poisoning or MAC address spoofing. Large numbers of ARP request broadcasts could cause the host MAC address table to overflow and prevent the host from communicating on the network.
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.*
12 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? RT1 will send an ARP reply with its Fa0/0 MAC address. PC2 will send an ARP reply with its MAC address. RT1 will send an ARP reply with the PC2 MAC address. SW1 will send an ARP reply with its Fa0/1 MAC address. SW1 will send an ARP reply with the PC2 MAC address.
PC2 will send an ARP reply with its MAC address.*
37. Fill in the blank. A collision fragment, also known as a ________ frame, is a frame of fewer than 64 bytes in length.
RUNT
23. Match the seven fields of an Ethernet frame to their respective contents. (Not all options are used.) Field 1-7 Sort elements Start Frame Delimiter -> Source MAC Address -> Encapsulated Data -> Preamble -> Destination MAC Address -> Length/Type -> Frame Check Sequence ->
Start Frame Delimiter -> Field 2 Source MAC Address -> Field 4 Encapsulated Data -> Field 6 Preamble -> Beginning of frame - Field 1 Destination MAC Address -> Field 3 Length/Type -> Field 5 Frame Check Sequence -> End of frame - Field 7
19 Which statement is true about MAC addresses? The first three bytes are used by the vendor assigned OUI. MAC addresses are implemented by software. The ISO is responsible for MAC addresses regulations. A NIC only needs a MAC address if connected to a WAN.
The first three bytes are used by the vendor assigned OUI.*
24. What happens to runt frames received by a Cisco Ethernet switch? The frame is dropped. The frame is returned to the originating network device. The frame is broadcast to all other devices on the same network. The frame is sent to the default gateway.
The frame is dropped.
11 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? (Choose three.) The auto-MDIX feature will configure the interfaces eliminating the need for a crossover cable. The connection will not be possible unless the administrator changes the cable to a crossover cable. The duplex capability has to be manually configured because it cannot be negotiated. If both switches support different speeds, they will each work at their own fastest speed. The link between switches will work as full-duplex. 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 link between the switches will work at the fastest speed that is supported by both switches.* The auto-MDIX feature will configure the interfaces eliminating the need for a crossover cable.*
20 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. The switch will forward the frame to all ports except port 4. The switch will forward the frame only to port 2. The switch will discard the frame. The switch will forward the frame only to ports 1 and 3.
The switch will forward the frame to all ports except port 4.*
36. Which statement describes the treatment of ARP requests on the local link? They must be forwarded by all routers on the local network. They are received and processed by every device on the local network. They are dropped by all switches on the local network. They are received and processed only by the target device.
They are received and processed by every device on the local network.*
31. What is auto-MDIX? a type of Cisco switch an Ethernet connector type a type of port on a Cisco switch a feature that detects Ethernet cable type
a feature that detects Ethernet cable type*
18 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 Cisco Express Forwarding instance a routed port a trunk interface a switched virtual interface
a routed port*
6 How does adding an Ethernet line card affect the form factor of a switch? by increasing the back plane switching speed by expanding the port density by expanding the NVRAM capacity by making the switch stackable
by expanding the port density*
1. Match the characteristic to the forwarding method (Not all options are used) Sort elements cut-through (A) -> cut-through (B) -> cut-through (C) -> store-and-forward (D) -> store-and-forward (E) -> store-and-forward (F) ->
cut-through (A) -> low latency (A) cut-through (B) -> may forward runt frames (B) cut-through (C) -> begins forwarding when the destination address is received (C) store-and-forward (D) -> always stores the entire frame (D) store-and-forward (E) -> checks the CRC before forwarding (E) store-and-forward (F) -> checks the frame length before forwarding (F)
9 What is the purpose of the preamble in an Ethernet frame? is used to identify the destination address is used to identify the source address is used as a padding for data is used for timing synchronization
is used for timing synchronization*
29. What addressing information is recorded by a switch to build its MAC address table? the destination Layer 3 address of incoming packets the destination Layer 2 address of outgoing frames the source Layer 3 address of outgoing packets the source Layer 2 address of incoming frames
the source Layer 2 address of incoming frames
32. 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 false
true*
