Computer-science_A-level_Cie
-
computers-and-components6 主题
-
logic-gates-and-logic-circuits2 主题
-
central-processing-unit-cpu-architecture6 主题
-
assembly-language-4 主题
-
bit-manipulation1 主题
-
operating-systems3 主题
-
language-translators2 主题
-
data-security3 主题
-
data-integrity1 主题
-
ethics-and-ownership3 主题
-
database-concepts3 主题
-
database-management-systems-dbms-1 主题
-
data-definition-language-ddl-and-data-manipulation-language-dml1 主题
-
computational-thinking-skills1 主题
-
algorithms14 主题
-
data-types-and-records2 主题
-
arrays2 主题
-
files1 主题
-
introduction-to-abstract-data-types-adt1 主题
-
programming-basics1 主题
-
constructs2 主题
-
structured-programming1 主题
-
program-development-life-cycle2 主题
-
program-design-2 主题
-
program-testing-and-maintenance3 主题
-
user-defined-data-types1 主题
-
file-organisation-and-access-3 主题
-
floating-point-numbers-representation-and-manipulation3 主题
-
protocols2 主题
-
circuit-switching-packet-switching1 主题
-
processors-parallel-processing-and-virtual-machines5 主题
-
boolean-algebra-and-logic-circuits4 主题
-
purposes-of-an-operating-system-os3 主题
-
translation-software3 主题
-
encryption-encryption-protocols-and-digital-certificates3 主题
-
artificial-intelligence-ai4 主题
-
recursion1 主题
-
programming-paradigms4 主题
-
object-oriented-programming7 主题
-
file-processing-and-exception-handling2 主题
-
data-representation5 主题
-
multimedia3 主题
-
compression2 主题
-
networks-and-the-internet11 主题
protocols
SSL/TLS
What is SSL?
-
SSL (Secure Sockets Layer) is a security protocol used to encrypt data sent over the internet
-
Helps to prevent eavesdropping, tampering, or man-in-the-middle attacks
-
Commonly used for:
-
Protecting websites
-
Online payments
-
Login credentials
-
-
Creates a secure connection between a web server and a browser
What is TLS?
-
TLS (Transport Layer Security) is the successor to SSL
-
It performs the same functions but is more secure and efficient
-
Modern websites use TLS, although people often still refer to it as “SSL”
-
When you see HTTPS in the browser, it means TLS/SSL encryption is active
-
How SSL/TLS works with digital certificates
-
When you visit a secure website (e.g.
https://), the server sends your browser its digital certificate -
The certificate contains:
-
The server’s public key
-
Information about the website and Certificate Authority (CA)
-
A digital signature from the CA
-
-
Your browser checks that the certificate is valid and trusted using the CA’s public key
-
If trusted, a secure connection is established, often using a shared secret key (symmetric encryption) created during the handshake
Summary: What a digital certificate does
|
Component |
Purpose |
|---|---|
|
Public key |
Used by your browser to create secure communication |
|
Website identity |
Shows who owns the key |
|
Certificate Authority |
Signs the certificate to confirm it’s trustworthy |
|
Browser validation |
Uses the CA’s public key to verify the certificate |
Examiner Tips and Tricks
-
TLS has replaced SSL — but both are encryption protocols used with digital certificates
-
Always mention digital certificates when explaining how websites create secure connections
Responses