Difference Between SSL and TLS

The main difference between SSL and TLS is that the SSL is a protocol that provides communication security in a computer network while the TSL protocol is an evolution of the SSL protocol and consists of additional privacy and security features.

SSL is a protocol used to send information securely through the network. Websites use SSL to secure user account pages and for online checkouts. It encrypts the data to avoid a third party accessing the transmitting data. On the other hand, TLS protocol is a successor to SSL. It provides privacy, integrity, and protection to the data. It allows communication across the network without interference by eavesdropping and tampering. In brief, the TLS is more secure and efficient than the SSL.

Key Areas Covered

1. What is SSL
     – Definition, Functionality
2. What is TLS
     – Definition, Functionality
3. Difference Between SSL and TLS
     – Comparison of Key Differences

Key Terms

Communication Security, SSL, TSL

What is SSL

SSL is a protocol developed by Netscape Communications. It allows web browsers and web servers to communicate securely. It is one of the most popular web security mechanisms. This protocol works between the application layer and the transport layer. Thus, the SSL layer can be considered as an additional layer in the TCP/IP protocol.

First, the data in the application layer is passed to the SSL layer. The SSL layer performs encryption on the received data. Moreover, it adds an exception information header to the data. This additional new header is called the SSL header. Then, the data in the SSL layer is passed to the transport layer. The transport layer adds its own header and passes to the next layer, which is the internet layer. Finally, the data is transmitted to the destination in the physical layer.

At the destination, the data travels through physical, network and transport layers. In the SSL layer, the encrypted data is decrypted. Finally, the original data is transmitted to the application layer in the destination computer.

What is TLS

TLS is a protocol that is used to ensure secure communication. It is used for web browsing, email, voice over IP (VoIP), etc.  It mainly provides privacy and data integrity among two or more communication parties.

When using TLS, the connection between the client and the server is secure as it uses symmetric cryptography to encrypt the data.  Public key cryptography is used to authenticate the communicating parties. Moreover, each message goes through a message integrity check using a message authentication code. It prevents undetected loss or changes in the data during transmission. Therefore, the connection becomes more reliable.

Additionally, TSL provides additional privacy related to properties such as forward secrecy. It helps to avoid using past encryption keys to decrypt future TLS records. TSL also provides methods for exchanging keys, encrypting data and authenticating message integrity.

There are two sub-protocols in TLS called TLS handshake and TLS record protocols. The TLS Handshake protocol allows the client and the server to authenticate each other and to select an encryption algorithm before sending data. TLS record protocol helps to make the connection secure and reliable.

Difference Between SSL and TLS

Definition

SSL is the standard security protocol for establishing an encrypted link between a web server and a browser.  TLS is a protocol that provides communication security between client/server applications that communicate with each other over the internet.

Introduction

SSL was introduced in the year 1994 by Netscape Communications and TLS was introduced in 1999 by the Internet Engineering Task Force (IETF).

Long Form

Secure Socket Layer is the long form of SSL while Transport Layer Security is the long form of TSL.

Complexity

TLS is a complex protocol than SSL. It uses a message authentication code, key material generation, etc. This is one main difference between SSL and TLS.

Security

Also, the additional security feature in TLS is another important difference between SSL and TLS. TLS is more secure than SSL.

Conclusion

SSL and TLS are two protocols that are used for secure communication. Both of them are cryptographic protocols. The difference between SSL and TLS is that the SSL is a protocol that provides communication security in a computer network while the TSL protocol is an evolution of the SSL protocol and consists of additional privacy and security features.

Reference:

1. Transport Layer Security – Applied Cryptography, Udacity, 3 June 2012, Available here.
2. “Transport Layer Security.” Wikipedia, Wikimedia Foundation, 30 Aug. 2018, Available here.
3. “What Is Transport Layer Security (TLS)? – Definition from Techopedia.” Techopedia.com, Available here.
4. “What Is Transport Layer Security (TLS)? – Definition from WhatIs.com.” SearchSecurity, TechTarget, Available here.

Image Courtesy:

1. “3400555” (CC0) via Pixabay