Free 4A0-100 Practice Test Questions 2026

A 24 port Ethernet switch is configured with VLAN 100 on ports 1 - 8, VLAN 200 on ports 9 - 16
and VLAN 300 on ports 17 - 24. Which of the following describes the behavior of the switch when
a broadcast frame is received on port 1?

A.

The switch will discard the broadcast frame because there is no specific destination address.

B.

The switch will flood the broadcast frame on all ports on which the switch has seen frames from
attached devices

C.

The switch will flood the broadcast frame on ports 2 to 8.

D.

The switch will flood the broadcast frame on all 24 ports.

The method by which Ethernet frames are associated to a specific VLAN is referred to as:

A.

Segmenting

B.

Stacking

C.

Routing

D.

Tagging

What information is used to separate VLANs on a VLAN trunk that connects multiple VLANs?

A.

VLAN tag.

B.

IP Header.

C.

FCS.

D.

Priority Value.

Using Q-in-Q Virtual Local Area Network (VLAN) stacking, how does a carrier differentiate one
customers traffic from that of another?

A.

The provider edge (PE) switch adds an additional field called a PE tag to the customers Layer 2
data.

B.

The PE switch replaces the customers VLAN tag with acarrier-assigned tag.

C.

The PE switch adds a second VLAN tag to identify the customers traffic on the carriers network

D.

The PE switch assigns a customer-specific priority label to the customers traffic.

What is the purpose of the Data Link Layer in the OSI model?

A.

The Data Link Layer is responsible for encapsulating the packet into a frame for transmission on
the transmission media.

B.

The Data Link Layer is responsible for encapsulating the packet into an IP header androuting the
packet.

C.

The Data Link Layer is responsible for formatting the packet for applications such as JPEG format.

D.

The Data Link Layer is responsible for timing of the signals on the transmission media

Which of the following is typically a characteristic of Layer 2 framing?

A.

Provides a universal addressing scheme to uniquely identify destinations in the network.

B.

The size of the Layer 2 frame cannot exceed 1518 bytes.

C.

Provides error checking of the frame contents after transmission.

D.

All the above.

Which of the following is NOT an example of a Layer 2 protocol?

A.

POS

B.

IP

C.

ATM

D.

Frame Relay

E.

Ethernet

Why is the address field in a PPP header always set to "11111111"?

A.

PPP supports multipoint access networks with many stations. The all 1's acts as a broadcast.

B.

PPP supports multipoint access networks with many stations. The all 1's acts as a multicast.

C.

PPP supports point-to-point networks only. The address field is fixed.

D.

PPP supports point-to-point networks only. The address field can change dynamically since every
station is assigned a PPP address.

Which ATM adaptation layer is commonly used for transporting IP datagrams or non-real time
data?

A.

AAL0

B.

AAL1

C.

AAL2

D.

AAL3/4

E.

AAL5

Which of the following is a characteristic of ATM?

A.

Application data is transported in 53-byte cells.

B.

ATM circuits are identified by aVPI/VCI value.

C.

Provides enhanced QoS support with 5 classes of service.

D.

Ideal for multiple services on the same physical line.

E.

All of the above.

F.

None of the above

What is the basic unit of framing in SONET and the bit rate for its transmission?

A.

STS-1 with a bit rate of 1.544 Mbit/s

B.

STS-1 with a bit rate of 2.048 Mbit/s

C.

STS-1 with a bit rate of 51.84 Mbit/s

D.

STS-1 with a bit rate of 155.52 Mbit/s

What is the basic unit of framing in SDH and the bit rate for its transmission?

A.

STM-1 with a bit rate of 1.544 Mbit/s

B.

STM-1 with a bit rate of 2.048 Mbit/s

C.

STM-1 with a bit rate of 51.84 Mbit/s

D.

STM-1 with a bit rate of 155.52 Mbit/s