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Protocols ( A Level)


Secure Sockets Layer

Developed by Netscape for their browser





Transport Layer Security

Developed by a working group, based on SSL Version 3.1

Cryptographic Protocol used for HTTP and non-HTTP traffic.

TLS Video

TLS Handshake

SSL Certificates

SSL Certificates

Detailed process 

Digital Signatures


Digital certificates are not just used for SSL encryption, they can also be used to verify emails and documents sent from person to person through the use of a digital signature.

TLS / SSL certificate

Email Certificate

Digital Signature

Code Signing Certificate



CIE Resource

Heartbleed Bug

Teacher Presentation

Past Paper Questions

S16 31 Qn 2

N16 31 Qn 6

S17 31 Qn 2c

N17 31 Qn 4

M19 31 Qn5

N19 31 Qn 8

S20 Qn8