CS6250 COMPUTER NETWORK EXAM 1
(2026 Edition) | Full Practice Questions
with Confirmed Answers | 100% Accurate
| Graded A+
• What does the transport layer provide? Answer: The transport layer
provides an end-to-end connection between two applications running on
different hosts. The transport layer provides this logical connection
regardless of whether the hosts are in the same network.
• What is a packet for the transport layer called? Answer: A segment. It
takes a message from the application layer and appends its own header.
• Why do we need an additional layer between the application and
network layer? Answer: The network layer offers a best-effort delivery
service model. According to this model, the network layer makes the
best effort to deliver data packets. Thus, it doesn't guarantee the delivery
packets or integrity. The transport layer allows application programmers
to develop applications assuming a standard set of functionalities
provided by the transport layer.
• What are the two main protocols within the transport layer? Answer:
The User Datagram Protocol (UDP) and Transmission Control Protocol
(TCP). UDP provides basic functionality and relies on the application
layer to implement the remaining. On the other hand, TCP provides
strong primitives to make end-to-end communication more reliable and
cost-effective.
, • What is multiplexing, and why is it necessary? Answer: Multiplexing
is the ability for a host to run multiple applications to use the network
simultaneously. It's necessary because we need a mechanism to
distinguish the many processes sharing the same IP address on the same
host. Combining data from multiple sources and sending it over the
same communication channel.
• How does the transport layer solve this problem? Answer: By using
additional identifiers known as ports. Each application binds itself to a
unique port number my opening sockets.
• What is demultiplexing? Answer: The job of delivering the data
included in the transport-layer segment to the appropriate socket.
Separating incoming data and delivering it to the correct application.
• How are sockets identified? Answer: Based on special fields such as
the source port number field and destination port number field.
• What are the two types of multiplexing and demultiplexing? Answer:
Connectionless and connection-oriented.
• Explain connectionless multiplexing and demultiplexing. Answer: This
is essentially a UDP connection. To identify a UDP socket at the
destination, you need a destination IP and a port number. For a normal
transaction. Host A sends the source port to the network layer, the
packet is sent with best-effort delivery, then the destination host receives
(2026 Edition) | Full Practice Questions
with Confirmed Answers | 100% Accurate
| Graded A+
• What does the transport layer provide? Answer: The transport layer
provides an end-to-end connection between two applications running on
different hosts. The transport layer provides this logical connection
regardless of whether the hosts are in the same network.
• What is a packet for the transport layer called? Answer: A segment. It
takes a message from the application layer and appends its own header.
• Why do we need an additional layer between the application and
network layer? Answer: The network layer offers a best-effort delivery
service model. According to this model, the network layer makes the
best effort to deliver data packets. Thus, it doesn't guarantee the delivery
packets or integrity. The transport layer allows application programmers
to develop applications assuming a standard set of functionalities
provided by the transport layer.
• What are the two main protocols within the transport layer? Answer:
The User Datagram Protocol (UDP) and Transmission Control Protocol
(TCP). UDP provides basic functionality and relies on the application
layer to implement the remaining. On the other hand, TCP provides
strong primitives to make end-to-end communication more reliable and
cost-effective.
, • What is multiplexing, and why is it necessary? Answer: Multiplexing
is the ability for a host to run multiple applications to use the network
simultaneously. It's necessary because we need a mechanism to
distinguish the many processes sharing the same IP address on the same
host. Combining data from multiple sources and sending it over the
same communication channel.
• How does the transport layer solve this problem? Answer: By using
additional identifiers known as ports. Each application binds itself to a
unique port number my opening sockets.
• What is demultiplexing? Answer: The job of delivering the data
included in the transport-layer segment to the appropriate socket.
Separating incoming data and delivering it to the correct application.
• How are sockets identified? Answer: Based on special fields such as
the source port number field and destination port number field.
• What are the two types of multiplexing and demultiplexing? Answer:
Connectionless and connection-oriented.
• Explain connectionless multiplexing and demultiplexing. Answer: This
is essentially a UDP connection. To identify a UDP socket at the
destination, you need a destination IP and a port number. For a normal
transaction. Host A sends the source port to the network layer, the
packet is sent with best-effort delivery, then the destination host receives
