Hypertext Transfer Protocol Secure

Hypertext Transfer Protocol Secure
Name	Hypertext Transfer Protocol Secure
Developer	Internet Engineering Task Force
Introduced	February 1994
Based on	Hypertext Transfer Protocol
Osi layer	Application layer
Port	443
Rfcs	RFC 2818, RFC 8446

Hypertext Transfer Protocol Secure. It is a secure extension of the foundational Hypertext Transfer Protocol used for communication across the World Wide Web. Developed to provide authentication, encryption, and data integrity, it is the primary protocol for secure data transmission between a user's web browser and a website. Its widespread implementation is fundamental to modern e-commerce, online banking, and the protection of sensitive information on the Internet.

Overview

The protocol was initially developed by Netscape Communications Corporation in 1994 for its Netscape Navigator browser. It was designed to secure transactions over the nascent commercial Internet, with early adoption by financial institutions like Bank of America. The core goal was to create a secure channel over an inherently insecure network, preventing eavesdropping and tampering by intermediaries. Its development and standardization were later taken over by the Internet Engineering Task Force, with key specifications published as RFC 2818. The protocol functions by layering security provisions atop the standard Transmission Control Protocol transport mechanism, typically operating on the designated TCP port 443.

Technical details

The security is achieved by combining Hypertext Transfer Protocol with a cryptographic protocol suite, originally Secure Sockets Layer and later its successor, Transport Layer Security. The process begins with a handshake phase where the client and server negotiate encryption algorithms and the server authenticates itself using a digital certificate issued by a trusted certificate authority like DigiCert or Let's Encrypt. This establishes a symmetric session key for efficient encryption of the actual data payload. The underlying record protocol then fragments, compresses, and encrypts the Hypertext Transfer Protocol data, ensuring confidentiality. The entire suite operates within the application layer of the Internet protocol suite, directly interfacing with applications like Google Chrome and Apache HTTP Server.

Security features

Primary security features include strong encryption using algorithms like Advanced Encryption Standard to prevent eavesdropping and ensure confidentiality. Message authentication codes provide data integrity, guaranteeing that transmitted data is not altered in transit. Server authentication via Public key infrastructure certificates allows clients to verify they are communicating with the legitimate server and not a malicious impostor, mitigating man-in-the-middle attack risks. Optionally, the protocol can be configured for mutual authentication, requiring certificates from both the server and the client, a practice sometimes used in sensitive environments like the United States Department of Defense.

Adoption and usage

Initial adoption was slow due to computational overhead and certificate costs, but it became ubiquitous following high-profile security incidents and advocacy by organizations like the Electronic Frontier Foundation. A major push came from Google when it began using the protocol as a ranking signal in its search engine algorithms. Today, it is the default for most major websites, enforced by browsers such as Mozilla Firefox and Microsoft Edge, which display warnings for non-secure connections. Its use is mandated by regulations like the Payment Card Industry Data Security Standard for any page handling credit card information and is critical for services like PayPal, Gmail, and Facebook.

Differences from HTTP

The most apparent difference is the use of the `https://` Uniform Resource Locator scheme versus `http://`. Communication occurs over TCP port 443 instead of the standard port 80. While Hypertext Transfer Protocol transmits data in plaintext, the secure version encrypts all header and payload data. This encryption prevents passive observers on networks like public Wi-Fi from reading session contents. Furthermore, it provides authentication, giving users cryptographic assurance of a website's identity, which is absent in plain Hypertext Transfer Protocol. These differences are visually indicated in browsers through a padlock icon in the address bar.

Vulnerabilities and attacks

Despite its strengths, the ecosystem is not impervious to threats. Vulnerabilities in underlying protocols, such as the POODLE attack against Secure Sockets Layer 3.0, have required deprecation of older versions. Implementation flaws, like the Heartbleed bug in OpenSSL, have exposed private keys and memory contents. Attacks often target the certificate authority infrastructure, as seen in the compromise of DigiNotar, which led to fraudulent certificate issuance. Other methods include SSL stripping attacks, which downgrade connections, and exploiting weaknesses in cipher suites that use algorithms like RC4. Continuous updates to the Transport Layer Security standard and diligent server configuration are necessary to mitigate these risks.

Category:Internet protocols Category:Computer security Category:World Wide Web