Chapter 2- Ethernet Networking and Data Encapsulation Flashcards
___________ on an Ethernet network is the retransmission delay that’s enforced when a collision occurs.
A. Backoff
B. Carriersense C. Forwarddelay
D. Jamming
A. Backoff on an Ethernet network is the retransmission delay that’s enforced when a collision occurs. When that happens, a host will only resume transmission after the forced time delay has expired. Keep in mind that after the backoff has elapsed, all stations have equal priority to transmit data.
A network interface port has collision detection and carrier sensing enabled on a shared twisted-pair network. From this statement, what is known about the network interface port?
A. This is a 10 Mbps switch port.
B. This is a 100 Mb/s switch port.
C. This is an Ethernet port operating at half-duplex.
D. This is an Ethernet port operating at full-duplex.
E. This is a port on a network interface card in a PC
C. Half-duplex Ethernet networking uses a protocol called Carrier Sense Multiple Access with Collision Detection (CSMA/CD), which helps devices share the bandwidth evenly while preventing two devices from transmitting simultaneously on the same network medium.
For what two purposes does the Ethernet protocol use physical addresses? (Choose two.)
A. To uniquely identify devices at layer 2
B. To allow communication with devices on a different network C. To differentiate a layer 2 frame from a layer 3 packet
D. To establish a priority system to determine which device gets to transmit first E. To allow communication between different devices on the same network
F. To allow detection of a remote device when its physical address is unknown
A, E. Physical addresses or MAC addresses are used to identify devices at layer 2. MAC addresses are only used to communicate on the same network. To communicate on different network, we have to use layer 3 addresses (IP addresses).
In an Ethernet network, under what two scenarios can devices transmit? (Choose two.)
A. When they receive a special token
B. When there is a carrier
C. When they detect that no other devices are sending
D. When the medium is idle
E. When the server grants access
C, D. An Ethernet network is a shared environment, so all devices have the right to access the medium. If more than one device transmits simultaneously, the signals collide and cannot reach the destination.If a device detects another device is sending, it will wait for a specified amount of time before attempting to transmit. When there is no traffic detected, a device will transmit its message. While this transmission is occurring, the device continues to listen for traffic or collisions on the LAN. After the message is sent, the device returns to its default listening mode.
When configuring a terminal emulation program, which of the following is an incorrect setting? A. Bit rate: 9600 B. Parity:None C. Flow control: None D. Data bits: 1
D. When you set up the connection, use these settings: Bits per sec: 9600 Data bits: 8 Parity: None Stop bits: 1 Flow control: None
Which part of a MAC address indicates whether the address is a locally or globally administered address?
A. FCS
B. I/G bit C. OUI
D. U/L bit
D. When set to 0, this bit represents a globally administered address, as specified by the IEEE, but when it’s a 1, it represents a locally governed and administered address.
Which of the following is not one of the actions taken in the operation of CSMA/CD when a collision occurs?
A. A jam signal informs all devices that a collision occurred.
B. The collision invokes a random backoff algorithm on the systems involved in the collision.
C. Each device on the Ethernet segment stops transmitting for a short time until its backoff timer expires.
D. All hosts have equal priority to transmit after the timers have expired.
C. Each device on the Ethernet segment stops transmitting for a short time until its backoff timer expires.
Which of the following statements is false with regard to Ethernet?
A. There are very few collisions in full-duplex mode.
B. A dedicated switch port is required for each full-duplex node.
C. The host network card and the switch port must be capable of operating in full- duplex mode to use full-duplex.
D. The default behavior of 10Base-T and 100Base-T hosts is 10 Mbps half-duplex if the autodetect mechanism fails.
A. There are no collisions in full-duplex mode.
1000Base-T
1000Base-SX
10Base-T
100Base-TX
The given cable types are matched with their standards in the following table. IEEE 802.3u 100Base-Tx IEEE 802.3 10Base-T IEEE 802.3ab 1000Base-T IEEE 802.3z 1000Base-SX
The cable used to connect to the console port on a router or switch is called a \_\_\_\_\_\_\_\_\_ cable. A. Crossover B. Rollover C. Straight-through D. Full-duplex
B. Although rolled cable isn’t used to connect any Ethernet connections together, you can use a rolled Ethernet cable to connect a host EIA-TIA 232 interface to a router console serial communication (COM) port
Which of the following items does a socket comprise?
A. IP address and MAC address B. IP address and port number
C. Port number and MAC address
D. MAC address and DLCI
B. If you’re using TCP, the virtual circuit is defined by the source and destination port number plus the source and destination IP address and called a socket.
Which of the following hexadecimal numbers converts to 28 in decimal?
A. 1c B. 12 C. 15 D. ab
A. The hex value 1c is converted as 28 in decimal.
0000 is what number in hex
0 is this number in binary
0001 is this number in hex
1 is this hex number in binary
0010 is this number in hex
2 in hex is this number in binary
0011 is this number in hex
3 in hex is this number in binary
