CS6250 COMPUTER NETWORK EXAM 2
EXAM SCRIPT COMPLETE QUESTIONS AND
ANSWERS EXPERT CERTIFIED FULL
SOLUTION GRADED A+
⩥ Layered Architecture.
Answer: Each protocol layer offers different services.
⩥ Layered Architecture Advantages.
Answer: - Scalability,
- Flexibility
- Ease of adding / removing components making it easier for
cost-effective implementations.
⩥ Layered Architecture Disadvantages.
Answer: - Some layers functionality depends on the information
from the other layer and violates the goal of layer separation;
- One layer may duplicate lower layer functionalities
- Overhead both in computation
- Overhead in message headers caused by abstraction barriers
between layers.
,⩥ OSI and Five-Layered Internet model Similarities.
Answer: Many of the layers are the same
⩥ OSI and Five-Layered Internet model Differences.
Answer: - Three of the layers are combined in the 5-layered
model.
- Specifically the five-layer model combines the
- Application
- Presentation
- Session layers
from the OSI model into a single Application layer.
⩥ What are sockets?.
Answer: - A network socket is a software structure within a
network node of a computer network that serves as an endpoint
for sending and receiving data across the network.
- The structure and properties of a socket are defined by an
application programming interface (API) for the networking
architecture.
- Sockets are created only during the lifetime of a process of an
application running in the node.
,- ."A process sends messages into, and receives messages from,
the network through a software interface called a socket.
- Let's consider an analogy to help us understand processes and
sockets. A process is analogous to a house and its socket is
analogous to its door....a socket is the interface between the
application layer and the transport layer within a host." - Kurose
and Ross, 2.1
⩥ Describe each layer of the OSI model..
Answer: - Application layer: Service, Interface, Protocol.
- Presentation layer: Plays intermediate role of formatting the
information received from the layer below and delivering it to
the application layer.
- Session layer: Responsible for the mechanism that manages the
different transport streams that belong to the same session
between end-user and application process.
- Transport layer: Responsible for the end-to-end
communication between end hosts.
, Network layer: This layer is responsible for moving the packet
of information, called a datagram, from one host to another.
- Data Link layer: Responsible for moving the frames from one
node (host or router) to the next node.
- Physical layer: This layer is the actual hardware responsible to
transfer bits within a frame between two nodes c
⩥ OSI Model Application Layer.
Answer: - Service, Interface, Protocol.
Ex: Turn on your smartphone and look at the list of apps.
(HTTP, SMTP, FTP, DNS)
⩥ OSI Model Presentation Layer.
Answer: - Plays intermediate role of formatting the information
received from the layer below and delivering it to the application
layer.
Ex: converting big endian to little endian.
EXAM SCRIPT COMPLETE QUESTIONS AND
ANSWERS EXPERT CERTIFIED FULL
SOLUTION GRADED A+
⩥ Layered Architecture.
Answer: Each protocol layer offers different services.
⩥ Layered Architecture Advantages.
Answer: - Scalability,
- Flexibility
- Ease of adding / removing components making it easier for
cost-effective implementations.
⩥ Layered Architecture Disadvantages.
Answer: - Some layers functionality depends on the information
from the other layer and violates the goal of layer separation;
- One layer may duplicate lower layer functionalities
- Overhead both in computation
- Overhead in message headers caused by abstraction barriers
between layers.
,⩥ OSI and Five-Layered Internet model Similarities.
Answer: Many of the layers are the same
⩥ OSI and Five-Layered Internet model Differences.
Answer: - Three of the layers are combined in the 5-layered
model.
- Specifically the five-layer model combines the
- Application
- Presentation
- Session layers
from the OSI model into a single Application layer.
⩥ What are sockets?.
Answer: - A network socket is a software structure within a
network node of a computer network that serves as an endpoint
for sending and receiving data across the network.
- The structure and properties of a socket are defined by an
application programming interface (API) for the networking
architecture.
- Sockets are created only during the lifetime of a process of an
application running in the node.
,- ."A process sends messages into, and receives messages from,
the network through a software interface called a socket.
- Let's consider an analogy to help us understand processes and
sockets. A process is analogous to a house and its socket is
analogous to its door....a socket is the interface between the
application layer and the transport layer within a host." - Kurose
and Ross, 2.1
⩥ Describe each layer of the OSI model..
Answer: - Application layer: Service, Interface, Protocol.
- Presentation layer: Plays intermediate role of formatting the
information received from the layer below and delivering it to
the application layer.
- Session layer: Responsible for the mechanism that manages the
different transport streams that belong to the same session
between end-user and application process.
- Transport layer: Responsible for the end-to-end
communication between end hosts.
, Network layer: This layer is responsible for moving the packet
of information, called a datagram, from one host to another.
- Data Link layer: Responsible for moving the frames from one
node (host or router) to the next node.
- Physical layer: This layer is the actual hardware responsible to
transfer bits within a frame between two nodes c
⩥ OSI Model Application Layer.
Answer: - Service, Interface, Protocol.
Ex: Turn on your smartphone and look at the list of apps.
(HTTP, SMTP, FTP, DNS)
⩥ OSI Model Presentation Layer.
Answer: - Plays intermediate role of formatting the information
received from the layer below and delivering it to the application
layer.
Ex: converting big endian to little endian.
