Hypertext Transfer Protocol Secure (HTTPS) is an extension of the Hypertext Transfer Protocol (HTTP). It is used for secure communication over a computer network, and is widely used on the Internet. In HTTPS, the communication protocol is encrypted using Transport Layer Security (TLS) or, formerly, Secure Sockets Layer (SSL). The protocol is therefore also referred to as HTTP over TLS, or HTTP over SSL.
Transport Layer Security (TLS) is a cryptographic protocol designed to provide communications security over a computer network. The protocol is widely used in applications such as email, instant messaging, and voice over IP, but its use in securing HTTPS remains the most publicly visible.
A public key infrastructure (PKI) is a set of roles, policies, hardware, software and procedures needed to create, manage, distribute, use, store and revoke digital certificates and manage public-key encryption. The purpose of a PKI is to facilitate the secure electronic transfer of information for a range of network activities such as e-commerce, internet banking and confidential email. It is required for activities where simple passwords are an inadequate authentication method and more rigorous proof is required to confirm the identity of the parties involved in the communication and to validate the information being transferred.
In cryptography, a public key certificate, also known as a digital certificate or identity certificate, is an electronic document used to prove the validity of a public key. The certificate includes information about the key, information about the identity of its owner, and the digital signature of an entity that has verified the certificate's contents. If the signature is valid, and the software examining the certificate trusts the issuer, then it can use that key to communicate securely with the certificate's subject. In email encryption, code signing, and e-signature systems, a certificate's subject is typically a person or organization. However, in Transport Layer Security (TLS) a certificate's subject is typically a computer or other device, though TLS certificates may identify organizations or individuals in addition to their core role in identifying devices. TLS, sometimes called by its older name Secure Sockets Layer (SSL), is notable for being a part of HTTPS, a protocol for securely browsing the web.
In cryptography, X.509 is an International Telecommunication Union (ITU) standard defining the format of public key certificates. X.509 certificates are used in many Internet protocols, including TLS/SSL, which is the basis for HTTPS, the secure protocol for browsing the web. They are also used in offline applications, like electronic signatures.
In cryptography, a web of trust is a concept used in PGP, GnuPG, and other OpenPGP-compatible systems to establish the authenticity of the binding between a public key and its owner. Its decentralized trust model is an alternative to the centralized trust model of a public key infrastructure (PKI), which relies exclusively on a certificate authority. As with computer networks, there are many independent webs of trust, and any user can be a part of, and a link between, multiple webs.
In cryptography, a certificate authority or certification authority (CA) is an entity that stores, signs, and issues digital certificates. A digital certificate certifies the ownership of a public key by the named subject of the certificate. This allows others to rely upon signatures or on assertions made about the private key that corresponds to the certified public key. A CA acts as a trusted third party—trusted both by the subject (owner) of the certificate and by the party relying upon the certificate. The format of these certificates is specified by the X.509 or EMV standard.
In cryptography and computer security, self-signed certificates are public key certificates that their users issue on their own behalf, as opposed to a certificate authority (CA) issuing them. These certificates are easy to make and do not cost money. However, they do not provide any trust value.
CyberTrust was a security services company formed in Virginia in November 2004 from the merger of TruSecure and Betrusted. Betrusted previously acquired GTE Cybertrust. Cybertrust acquired a large stake in Ubizen, a European security services firm based in Belgium, to become one of the largest information security firms in the world. It was acquired by Verizon Business in 2007. In 2015, the CyberTrust root certificates were acquired by DigiCert, Inc., a leading global Certificate Authority (CA) and provider of trusted identity and authentication services.
Comodo Security Solutions, Inc., also known as Sectigo, is a cybersecurity company headquartered in Bloomfield, New Jersey in the United States.
GeoTrust is a digital certificate provider. The GeoTrust brand was bought by Symantec from Verisign in 2010, but agreed to sell the certificate business in August 2017 to private equity and growth capital firm Thoma Bravo LLC. GeoTrust was the first certificate authority to use the domain-validated certificate method which accounts for 70 percent of all SSL certificates on the Internet. By 2006, GeoTrust was the 2nd largest certificate authority in the world with 26.7 percent market share according to independent survey company Netcraft.
GlobalSign was one of the first Certificate Authorities (CAs) to be WebTrust audited. It is a provider of identity and security solutions for the Internet of Things (IoT). As of January 2015, Globalsign was the 4th largest certificate authority in the world according to the Netcraft survey.
DigiCert, Inc. is an American digital security company headquartered in Lehi, Utah, with offices in Australia, Ireland, Japan, India, South Africa, Switzerland and United Kingdom. As a certificate authority (CA) and trusted third party, DigiCert provides the public key infrastructure (PKI) and validation required for issuing digital certificates or TLS/SSL certificates. These certificates are used to verify and authenticate the identities of organizations and domains and to protect the privacy and data integrity of users’ digital interactions with web browsers, email clients, documents, software programs, apps, networks and connected IoT devices.
The Certification Authority Browser Forum, also known as the CA/Browser Forum, is a voluntary consortium of certification authorities, vendors of Internet browser and secure email software, operating systems, and other PKI-enabled applications that promulgates industry guidelines governing the issuance and management of X.509 v.3 digital certificates that chain to a trust anchor embedded in such applications. Its guidelines cover certificates used for the SSL/TLS protocol and code signing, as well as system and network security of certificate authorities.
The Transport Layer Security (TLS) protocol provides the ability to secure communications across networks. This comparison of TLS implementations compares several of the most notable libraries. There are several TLS implementations which are free software and open source.
A TLS termination proxy is a proxy server that acts as an intermediary point between client and server applications, and is used to terminate and/or establish TLS tunnels by decrypting and/or encrypting communications. This is different to TLS pass-through proxies that forward encrypted (D)TLS traffic between clients and servers without terminating the tunnel.
DNS-based Authentication of Named Entities (DANE) is an Internet security protocol to allow X.509 digital certificates, commonly used for Transport Layer Security (TLS), to be bound to domain names using Domain Name System Security Extensions (DNSSEC).
Let's Encrypt is a non-profit certificate authority run by Internet Security Research Group (ISRG) that provides X.509 certificates for Transport Layer Security (TLS) encryption at no charge. It is the world's largest certificate authority, used by more than 300 million websites, with the goal of all websites being secure and using HTTPS. The Internet Security Research Group (ISRG), the provider of the service, is a public benefit organization. Major sponsors include the Electronic Frontier Foundation (EFF), the Mozilla Foundation, OVH, Cisco Systems, Facebook, Google Chrome, Internet Society, AWS, NGINX, and Bill and Melinda Gates Foundation. Other partners include the certificate authority IdenTrust, the University of Michigan (U-M), and the Linux Foundation.
DNS Certification Authority Authorization (CAA) is an Internet security policy mechanism that allows domain name holders to indicate to certificate authorities whether they are authorized to issue digital certificates for a particular domain name. It does this by means of a new "CAA" Domain Name System (DNS) resource record.
The Automatic Certificate Management Environment (ACME) protocol is a communications protocol for automating interactions between certificate authorities and their users' servers, allowing the automated deployment of public key infrastructure at very low cost. It was designed by the Internet Security Research Group (ISRG) for their Let's Encrypt service.
