Chapter 4: The Current Ethernet Specifications

Which contention method does 802.3 Ethernet use for collisions?

• CSMA/CD

• CSMA/CA

• Half-duplex

• Full-duplex

Which field in an Ethernet frame is used to check the integrity of the frame?

• SOF

• Preamble

• DA

• FCS

What is the significance of the preamble?

• The preamble allows the switch to allocate a buffer.

• The preamble allows the switch to sense collisions before data is transmitted.

• The preamble allows the switch to sync timing for the receipt of information to follow.

• The preamble allows the switch to read the sequence and acknowledge receipt of the frame.

In a layer 2 frame, where is the destination MAC address?

• The destination MAC address is the first 6 bytes after the preamble.

• The destination MAC address is the second 6 bytes after the preamble.

• The destination MAC address is the payload data.

• The destination MAC address is found in the preamble.

How many bits is the OUI assigned by the IEEE?

• 6 bits

• 22 bits

• 24 bits

• 48 bits

If the I/G or Individual/Group bit is set to 1 in the OUI portion of the MAC address, which statement is true?

• The MAC address is a unique individual computer by the IEEE.

• The MAC address is locally governed.

• The MAC address is a broadcast or multicast.

• The MAC address should always be broadcast.

If the L/G or Local/Group bit is set to 1 in the OUI portion of the MAC address, which statement is true?

• The MAC address is a unique individual computer by the IEEE.

• The MAC address is locally governed.

• The MAC address is a broadcast or multicast.

• The MAC address should always be broadcast.

Which is a reason that the Ethernet protocol uses physical addresses?

• It creates a differentiation between layer 2 and layer 3 communications.

• It defines a logical address scheme for devices.

• It uniquely identifies devices at layer 2.

• It allows the node to decide if the device is remote or local.

What is the 2-byte type field used for in an Ethernet frame?

• It defines the data type contained within the frame.

• It identifies the upper-layer protocol for the data contained within the frame.

• It is a calculation with the FCS to provide error detection.

• It describes the length of data contained within the frame.

What is the purpose of the State of Frame delimiter byte in a frame?

• It provides physical timing for the frame that follows.

• It divides the data and the physical timing portion of the frame.

• It provides a means for the receiving node to know when data begins.

• It delimits the destination and source MAC address.