Trang

chapter 5 CCNA V5.0 routing and switching 2013 /2014

Thứ Sáu, 27 tháng 12, 2013

chapter 5 routing & switching V5.0

Which statement is true about MAC addresses?
  • The first three bytes are used by the vendor assigned OUI

What is a characteristic of a contention-based access method?
  • It is a nondeterministic method

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 data link layer uses LLC to communicate with the upper layers of the protocol suite

What is the purpose of the preamble in an Ethernet frame?
  • is used for timing synchronization

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

Which two statements are correct about MAC and IP addresses during data transmission if NAT is not involved? (Choose two.)
  • 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

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
  • If a device receiving an ARP request has the destination IPv4 address, it responds with an ARP reply

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

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

What are two potential network problems that can result from ARP operation? (Choose two.)
  • 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

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 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

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

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

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 two statements describe a fixed configuration Ethernet switch? (Choose two.)
  • A fixed configuration switch may be stackable
  • The number of ports on the switch cannot be increased

How does adding an Ethernet line card affect the form factor of a switch?
  • By expanding the port density

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

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

What statement illustrates a drawback of the CSMA/CD access method?
  • Collisions can decrease network performance

Fill in the blank. The binary number 0000 1010 can be expressed as ______ in hexadecimal.
  • 0A    ("zero-a", not the letter o!)

Match...
  • Field 1 - Preamble
  • Field 2 - Start Frame Delimiter
  • Field 3 - Destination MAC Address
  • Field 4 - Source MAC Address
  • Field 5 - Length field
  • Field 6 - Data  Field
  • Field 7 - Frame Check Sequence

Match the characteristic to the forwarding method. (Not all options are used.)
Cut-through:
  • low latency 
  • may forward runt frames 
  • begins forwarding when the destination address is received 
Store and forward:
  • always stores the entire frame
  • checks the CRC before forwarding
  • checks the frame length before forwarding
A store-and-forward switch always stores the entire frame before forwarding, and checks its CRC and frame length. A cut-through switch can forward frames before receiving the destination address field, thus presenting less latency than a store-and-forward switch. Because the frame can begin to be forwarded before it is completely received, the switch may transmit a corrupt or runt frame. All forwarding methods require a Layer 2 switch to forward broadcast frames.

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

Không có nhận xét nào:

Đăng nhận xét