Email and IP security: Computer Networks Class Notes

Updated: Aug 18

Mobiprep has created last-minute notes for all topics of Computer networks to help you with the revision of concepts for your university examinations. So let’s get started with the lecture notes on Computer networks.

  1. Computer Networks - Basics

  2. Network Devices

  3. Network Models

  4. Physical Layer

  5. Network Layer

  6. Transport Layer and Congestion control

  7. Application Layer

  8. Web Security

  9. Email and IP Security


Our team has curated a list of the most important questions asked in universities such as DU, DTU, VIT, SRM, IP, Pune University, Manipal University, and many more. The questions are created from the previous year's question papers of colleges and universities.


  1. explain ssl, tls protocols?

  2. explain secure/multipurpose internet mail extensions?

  3. what is ipsec architecture?

Email and IP security


Question 1) Explain SSL, TLS protocols?

Answer) SSL

SSL – Secure Sockets Layer

SSL is a standard protocol for keeping an internet connection secure. It is used to protect the sensitive data sent between the source and destination. This is achieved by making sure that any data transferred between two systems remain impossible to read. It makes use of encryption algorithms to scramble data, and prevents hackers from reading it as it is sent over the communication channel.


TLS

TLS – Transport Layer Security

It is an updated version of SSL. This protocol also uses encryption to secure the data. It provides secure communication through implicit connections, while SSL uses explicit connections for this purpose. TLS is the successor of the SSL protocol.


 

Question 2) Explain secure/multipurpose internet mail extensions?

Answer) Secure/Multipurpose internet mail extensions are used to secure the e-mail data. This method is used to add cryptographic security to the e-mail. It uses asymmetric cryptography to encrypt the data. So, two keys (a public key and a private key) are used. the e-mail data is encrypted using the public key. The data can be decrypted only with the secret private key which is known only to the receiver. Unless the private key is known to the receiver, he/she cannot access the sensitive data in the e-mail.



 

Question 3) What is IPSec architecture?

Answer) IPSec – IP Security

The IP security architecture is used to secure the data traffic. It is used to ensure data confidentiality, integrity and authentication. Two protocols are used to provide security in the network. They are:

1. ESP (Encapsulation Security Payload)

This protocol is used to ensure data confidentiality. The ESP packet format is given below:


ESP packet in computer network class notes
ESP packet

Security Parameter Index(SPI):

This field is used to give a unique number to the connection build between the client and the server.

Sequence Number:

A unique Sequence number is assigned to every data packet. This is used to rearrange the packets at the receiver.

Payload Data:

Payload data refers to the actual data or the actual message. The Payload data is in encrypted format to achieve confidentiality.

Padding:

Padding refers to the extra bits added to the original message to ensure confidentiality.

Next Header:

Next header refers to the next payload or next actual data.


2. AH (Authentication Header)

The AH protocol is used to provide authentication and data integrity. The AH header is shown in the diagram given below:


AH header in computer networks class notes
AH header

Security Parameter Index(SPI):

This field is used to give a unique number to the connection build between the client and the server.

Sequence Number:

A unique Sequence number is assigned to every data packet. This is used to rearrange the packets at the receiver.

Payload Data:

Payload data refers to the actual data or the actual message. The Payload data is in encrypted format to achieve confidentiality.

Next Header:

Next header refers to the next payload or next actual data.

Integrity Checksum

This field is used to ensure data integrity using the checksum value.

The IPSec architecture is depicted below:


 IPSec architecture in computer network class notes
IPSec architecture





5 views0 comments