PPT: Application Layer | Computer Networks - Computer Science Engineering (CSE) PDF Download

Download, print and study this document offline
Please wait while the PDF view is loading
 Page 1


Application Layer
slides are modified from J. Kurose & K. Ross
Page 2


Application Layer
slides are modified from J. Kurose & K. Ross
2: Application Layer 2
Chapter 2: Application layer
r 2.1 Principles of network applications
r 2.2 Web and HTTP
r 2.3 FTP
r 2.4 Electronic Mail
v SMTP, POP3, IMAP
r 2.5 DNS
r 2.6 P2P applications
r 2.7 Socket programming with TCP
r 2.8 Socket programming with UDP
Page 3


Application Layer
slides are modified from J. Kurose & K. Ross
2: Application Layer 2
Chapter 2: Application layer
r 2.1 Principles of network applications
r 2.2 Web and HTTP
r 2.3 FTP
r 2.4 Electronic Mail
v SMTP, POP3, IMAP
r 2.5 DNS
r 2.6 P2P applications
r 2.7 Socket programming with TCP
r 2.8 Socket programming with UDP
2: Application Layer 3
Processes communicating
Process:
program running within a host
Client process:
initiates communication
Server process:
waits to be contacted
process sends/receives messages to/from its socket
identifier includes both IP address and port numbers
associated with process on host.
process
TCP with
buffers,
variables
socket
host or
server
process
TCP with
buffers,
variables
socket
host or
server
Internet
Controlled by OS
controlled by
app developer
Page 4


Application Layer
slides are modified from J. Kurose & K. Ross
2: Application Layer 2
Chapter 2: Application layer
r 2.1 Principles of network applications
r 2.2 Web and HTTP
r 2.3 FTP
r 2.4 Electronic Mail
v SMTP, POP3, IMAP
r 2.5 DNS
r 2.6 P2P applications
r 2.7 Socket programming with TCP
r 2.8 Socket programming with UDP
2: Application Layer 3
Processes communicating
Process:
program running within a host
Client process:
initiates communication
Server process:
waits to be contacted
process sends/receives messages to/from its socket
identifier includes both IP address and port numbers
associated with process on host.
process
TCP with
buffers,
variables
socket
host or
server
process
TCP with
buffers,
variables
socket
host or
server
Internet
Controlled by OS
controlled by
app developer
2: Application Layer 4
App-layer protocol defines
r Types of messages exchanged,
v e.g., request, response
r Message syntax:
v what fields in messages & how fields are delineated
r Message semantics
v meaning of information in fields
r Rules for when and how processes send & respond to
messages
Public-domain protocols: Proprietary protocols:
¨ defined in RFCs ¨ e.g., Skype
¨ allows for interoperability
¨ e.g., HTTP, SMTP
Page 5


Application Layer
slides are modified from J. Kurose & K. Ross
2: Application Layer 2
Chapter 2: Application layer
r 2.1 Principles of network applications
r 2.2 Web and HTTP
r 2.3 FTP
r 2.4 Electronic Mail
v SMTP, POP3, IMAP
r 2.5 DNS
r 2.6 P2P applications
r 2.7 Socket programming with TCP
r 2.8 Socket programming with UDP
2: Application Layer 3
Processes communicating
Process:
program running within a host
Client process:
initiates communication
Server process:
waits to be contacted
process sends/receives messages to/from its socket
identifier includes both IP address and port numbers
associated with process on host.
process
TCP with
buffers,
variables
socket
host or
server
process
TCP with
buffers,
variables
socket
host or
server
Internet
Controlled by OS
controlled by
app developer
2: Application Layer 4
App-layer protocol defines
r Types of messages exchanged,
v e.g., request, response
r Message syntax:
v what fields in messages & how fields are delineated
r Message semantics
v meaning of information in fields
r Rules for when and how processes send & respond to
messages
Public-domain protocols: Proprietary protocols:
¨ defined in RFCs ¨ e.g., Skype
¨ allows for interoperability
¨ e.g., HTTP, SMTP
2: Application Layer 5
Transport service requirements of common apps
Application
file transfer
e-mail
Web documents
real-time audio/video
stored audio/video
interactive games
instant messaging
Data loss
no loss
no loss
no loss
loss-tolerant
loss-tolerant
loss-tolerant
no loss
Throughput
elastic
elastic
elastic
audio: 5kbps-1Mbps
video:10kbps-5Mbps
same as above
few kbps up
elastic
Time Sensitive
no
no
no
yes, 100’s msec
yes, few secs
yes, 100’s msec
yes and no
Read More
21 videos|107 docs|66 tests

Up next

FAQs on PPT: Application Layer - Computer Networks - Computer Science Engineering (CSE)

1. What is the application layer in computer networking?
Ans. The application layer is the topmost layer in the OSI model of computer networking. It provides services and protocols that enable communication between applications running on different devices. It is responsible for tasks such as file transfer, email, web browsing, and remote access.
2. What are some common protocols used in the application layer?
Ans. Some common protocols used in the application layer include HTTP (Hypertext Transfer Protocol) for web browsing, SMTP (Simple Mail Transfer Protocol) for email communication, FTP (File Transfer Protocol) for file transfer, and DNS (Domain Name System) for translating domain names to IP addresses.
3. How does the application layer ensure reliable communication between applications?
Ans. The application layer does not directly ensure reliable communication between applications. It relies on lower layers in the network stack, such as the transport layer, to provide reliable data transfer. However, the application layer can implement mechanisms like error checking, retransmission, and flow control within the application itself to enhance reliability.
4. What role does the application layer play in network security?
Ans. The application layer plays a crucial role in network security. It can implement encryption and authentication mechanisms to ensure secure communication between applications. It also enables the implementation of access control policies, firewalls, and intrusion detection systems to protect against unauthorized access and attacks.
5. How does the application layer handle different types of data formats and protocols?
Ans. The application layer handles different types of data formats and protocols through the use of standardized protocols and APIs (Application Programming Interfaces). These protocols define how data is formatted, transmitted, and interpreted by applications. APIs provide a set of functions and methods that allow applications to interact with each other and exchange data in a standardized manner.
21 videos|107 docs|66 tests
Download as PDF

Up next

Explore Courses for Computer Science Engineering (CSE) exam
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev
Related Searches

Extra Questions

,

video lectures

,

Free

,

Summary

,

study material

,

MCQs

,

Previous Year Questions with Solutions

,

PPT: Application Layer | Computer Networks - Computer Science Engineering (CSE)

,

mock tests for examination

,

ppt

,

Important questions

,

Objective type Questions

,

PPT: Application Layer | Computer Networks - Computer Science Engineering (CSE)

,

shortcuts and tricks

,

Sample Paper

,

Exam

,

practice quizzes

,

Viva Questions

,

Semester Notes

,

pdf

,

PPT: Application Layer | Computer Networks - Computer Science Engineering (CSE)

,

past year papers

;