What company developed the Secure Sockets Layer (SSL) protocol?

Netscape developed the Secure Sockets Layer (SSL) protocol.

SSL was created in the 1990s to protect communications between web browsers and servers, especially as commercial activity began moving onto the World Wide Web. Taher Elgamal, Netscape’s chief scientist, is widely associated with the original protocol, and Netscape incorporated SSL into its Netscape Navigator browser and related web technologies.

SSL 1.0 was never publicly released because of serious security flaws. SSL 2.0 appeared in 1995 but had major weaknesses, including poor protection during the handshake and limitations involving virtual hosting. Netscape and collaborators redesigned the protocol as SSL 3.0, released in 1996.

TLS, or Transport Layer Security, later replaced SSL and became the standards-based successor. Although people still casually say “SSL certificate,” modern websites generally use TLS certificates and TLS protocol versions. RSA Security supplied important cryptographic technology, but it did not develop SSL itself.