1 Refer to the exhibit. Host A is communicating with host F. What happens to a frame sent from host A to host F as it travels over the Ethernet segments?
- The frame format is modified as it passes through each switch.
- The frame format remains the same across each Ethernet segment.*
- The frame format is modified as the media speed changed at switch B and switch E.
- The frame format is modified as the media material changes between copper and fiber at switch C and switch D.
2 Which of the following are specified by IEEE standards as sublayers of the OSI data link layer? (Choose two.)
- Logical Link Control*
- Logical Layer Control
- Media Access Control*
- Logical Link Communication
- Media Access Communication
- Physical Access Communication
3 In which two layers of the OSI model does Ethernet function? (Choose two.)
- data link*
4 Which statement describes how CSMA/CD on an Ethernet segment manages the retransmission of frames after a collision occurs?
- The first device to detect the collision has the priority for retransmission.
- The device with the lowest MAC address determines the retransmission priority.
- The devices on the network segment hold an election for priority to retransmit data
- The devices transmitting when the collision occurs DO NOT have priority for retransmission.*
5 Which two devices can provide full-duplex Ethernet connections? (Choose two.)
- Layer 2 switch*
6 Refer to the exhibit. The switch and workstation are administratively configured for full-duplex operation. Which statement accurately reflects the operation of this link?
- No collisions will occur on this link.*
- Only one of the devices can transmit at a time.
- The switch will have priority for transmitting data.
- The devices will default back to half duplex if excessive collisions occur.
7 Refer to the exhibit. All hosts are in listen mode. Host 1 and Host 4 both transmit data at the same time. How do the hosts respond on the network? (Choose two.)
- Hosts 1 and 4 may be operating full duplex so no collision will exist.
- The hub will block the port connected to Host 4 to prevent a collision.
- After the end of the jam signal, a backoff algorithm is invoked.*
- Hosts 1 and 4 are assigned shorter backoff values to provide them priority to access the media.
- If a host has data to transmit after the backoff period of that host, the host checks to determine if the line is idle, before transmitting.*
8 A router has an Ethernet, Token Ring, serial, and ISDN interface. Which interfaces will have a MAC address?
- serial and ISDN interfaces
- Ethernet and Token Ring interfaces*
- Ethernet and ISDN interfaces
- Token Ring and serial interfaces
9 What are three functions of a NIC in a PC? (Choose three.)
- A NIC connects the PC to the network media.*
- A NIC detects collisions on the Ethernet segment.*
- A NIC checks the formatting of data before it is transmitted.
- A NIC passes the contents of selected frames to the upper OSI layers.*
- A NIC acknowledges and retransmits data that was not received properly.
- A NIC discards frames when the destination IP address does not match the local host.
10 On a local area network, one workstation can send data on the line while it is receiving data. What type of data transfer does this describe?
- half duplex
- full duplex*
11 In an Ethernet LAN, how does the NIC know when it can transmit data?
- An Ethernet NIC transmits data as soon as the frame is received.
- An Ethernet NIC transmits data as soon as the NIC receives a token.
- An Ethernet NIC transmits data when it senses a collision.
- An Ethernet NIC transmits data after listening for the absence of a signal on the media.*
12 Which characteristics describe carrier sense multiple access collision detect (CSMA/CD)? (Choose three.)
- collision environment*
- first-come, first-served approach*
13 Why do hosts on an Ethernet segment that experience a collision use a random delay before attempting to transmit a frame?
- A random delay is used to ensure a collision-free link.
- A random delay value for each device is assigned by the manufacturer.
- A standard delay value could not be agreed upon among networking device vendors.
- +A random delay helps prevent the stations from experiencing another collision during the transmission.*
14 At what layer of the OSI model does a MAC address reside?
15 Where does the MAC address originate?
- DHCP server database
- configured by the administrator
- burned into ROM on the NIC card*
- network configuration on the computer
- included in the creation of the processor chip
16 When a collision occurs in a network using CSMA/CD, how do hosts with data to transmit respond after the backoff period has expired?
- The hosts return to a listen-before-transmit mode.*
- The hosts creating the collision have priority to send data.
- The hosts creating the collision retransmit the last 16 frames.
- The hosts extend their delay period to allow for rapid transmission.
17 Refer to the exhibit. The small office network shown in the exhibit consists of four computers connected through a hub. Which configuration would cause collisions and errors on the network?
- peer-to-peer shared resources
- administratively configured full duplex*
18 How many hexadecimal digits are in a MAC address?
19 Refer to the exhibit. A technician wants to increase the available bandwidth for the workstation by allowing the switch and the NIC on the workstation to transmit and receive simultaneously. What will permit this?
- crossover cable
Di Posting pada 11:30:50 31-09-2009
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