CNA 101 Chapter 4 Physical Layer 2026/2027 | Practice Questions
and Study Guide
The ________ layer of the OSI model sits at the bottom of the stack. It is part of the Network Access
layer of the TCP/IP model. - Correct answer✅✅ Physical
___ and ___ signals can distort and corrupt the data signals being carried by copper media. - Correct
answer✅✅ Electromagnetic Interference (EMI)
Radio Frequency Interference (RFI)
A disturbance caused by the electric or magnetic fields of a signal on one wire to the signal in an
adjacent wire. - Correct answer✅✅ Crosstalk
True or False? In telephone circuits, crosstalk can result in hearing part of another voice conversation
from an adjacent circuit. - Correct answer✅✅ True
Devices on a wireless network must be connected to a wireless __ or wireless ________. - Correct
answer✅✅ access point (AP)
router
True or False? An end-user device can have either a wireless local area network (WLAN) network
interface card (NIC), or an Ethernet NIC, but not both. - Correct answer✅✅ False. Some devices have
only one, but devices can have both types of NIC card.
Match the portion of the frame to the most accurate term.
Ethernet
IP
TCP
Data
, Segment
Frame
Packet
Data - Correct answer✅✅ Ethernet = Frame
IP = Packet
TCP = Segment
Data = Data
True or False? The physical layer is only concerned with wired network connections. - Correct
answer✅✅ False.
True or False? When a frame is encoded by the physical layer, all bits are sent over the media at the
same time. - Correct answer✅✅ False.
The physical layer of the receiving devices passes bits up to which higher level layer? - Correct
answer✅✅ Data link (layer 2)
What PDU is received by the physical layer for encoding and transmission? - Correct answer✅✅ Frame
The services and protocols in the TCP/IP suite are defined by the ____. - Correct answer✅✅ Internet
Engineering Task Force (IETF)
Name two of the three functional areas addressed by physical layer standards. - Correct answer✅✅
Physical Components
Encoding
Signaling
A method of converting a stream of data bits into a predefined "code" - Correct answer✅✅ Encoding
(or line encoding)
The way that bits are represented is called what? - Correct answer✅✅ Signaling method
and Study Guide
The ________ layer of the OSI model sits at the bottom of the stack. It is part of the Network Access
layer of the TCP/IP model. - Correct answer✅✅ Physical
___ and ___ signals can distort and corrupt the data signals being carried by copper media. - Correct
answer✅✅ Electromagnetic Interference (EMI)
Radio Frequency Interference (RFI)
A disturbance caused by the electric or magnetic fields of a signal on one wire to the signal in an
adjacent wire. - Correct answer✅✅ Crosstalk
True or False? In telephone circuits, crosstalk can result in hearing part of another voice conversation
from an adjacent circuit. - Correct answer✅✅ True
Devices on a wireless network must be connected to a wireless __ or wireless ________. - Correct
answer✅✅ access point (AP)
router
True or False? An end-user device can have either a wireless local area network (WLAN) network
interface card (NIC), or an Ethernet NIC, but not both. - Correct answer✅✅ False. Some devices have
only one, but devices can have both types of NIC card.
Match the portion of the frame to the most accurate term.
Ethernet
IP
TCP
Data
, Segment
Frame
Packet
Data - Correct answer✅✅ Ethernet = Frame
IP = Packet
TCP = Segment
Data = Data
True or False? The physical layer is only concerned with wired network connections. - Correct
answer✅✅ False.
True or False? When a frame is encoded by the physical layer, all bits are sent over the media at the
same time. - Correct answer✅✅ False.
The physical layer of the receiving devices passes bits up to which higher level layer? - Correct
answer✅✅ Data link (layer 2)
What PDU is received by the physical layer for encoding and transmission? - Correct answer✅✅ Frame
The services and protocols in the TCP/IP suite are defined by the ____. - Correct answer✅✅ Internet
Engineering Task Force (IETF)
Name two of the three functional areas addressed by physical layer standards. - Correct answer✅✅
Physical Components
Encoding
Signaling
A method of converting a stream of data bits into a predefined "code" - Correct answer✅✅ Encoding
(or line encoding)
The way that bits are represented is called what? - Correct answer✅✅ Signaling method
