Secure communication

Tor is a free overlay network for enabling anonymous communication. Built on free and open-source software and more than seven thousand volunteer-operated relays worldwide, users can have their Internet traffic routed via a random path through the network.

Computer security (also cybersecurity, digital security, or information technology (IT) security) is the protection of computer software, systems and networks from threats that can lead to unauthorized information disclosure, theft or damage to hardware, software, or data, as well as from the disruption or misdirection of the services they provide.

Mailfence is a Belgian encrypted email service with a focus on security and privacy that offers OpenPGP based end-to-end encryption and digital signatures for usage in emails. It was launched in November 2013 by ContactOffice Group, which has been operating an online collaboration suite since 1999.

Tuta, formerly Tutanota, is an end-to-end encrypted email app and a freemium secure email service. The service is advertisement-free; it relies on donations and premium subscriptions. As of June 2023, Tutanota's owners claimed to have over 10 million users of the product. The company announced a transition to 100% renewable electricity in March 2019. This decision coincided with employee participation in Fridays for Future protests. On 1st October 2024, Tuta launched its standalone encrypted calendar app. Tuta Mail has recently integrated post-quantum cryptography features through its new protocol - TutaCrypt replacing standard encryption methods like RSA-2048 and AES-256 for its newly created accounts after March 2024.

Proton Mail is a Swiss end-to-end encrypted email service launched in 2014 and operated by Proton AG, which also operates Proton VPN, Proton Drive, Proton Calendar, Proton Pass and Proton Wallet. Proton AG is owned by the nonprofit Proton Foundation. Proton Mail uses client-side encryption to protect email content and user data before they are sent to Proton Mail servers, unlike other common email providers such as Gmail and Outlook.com.

The Certification Authority Browser Forum, also known as the CA/Browser Forum, is a voluntary consortium of certification authorities, vendors of web browsers 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.

Whisper Systems was an American enterprise mobile security company that was co-founded by security researcher Moxie Marlinspike and roboticist Stuart Anderson in 2010. The company was acquired by Twitter in November 2011. Some of the company's software products were released under open-source licenses after the acquisition. An independent group called Open Whisper Systems later picked up the development of this open-source software, which led to the creation of the Signal Technology Foundation.

A data breach, also known as data leakage, is "the unauthorized exposure, disclosure, or loss of personal information".

iGap is a free Iranian instant messaging application for smart phones and personal computers. iGap allows users to interact with each other and exchange information through text, image, video, audio and other types of messages. iGap also supports P2P-based voice calls over the internet.

mailbox.org is an encrypted email service provider based in Germany. The encryption system uses PGP like most other encrypted email providers. It also features address books, calendars, video conferencing, online office and tasks management. It competes against Microsoft 365 and Google Workspace as a German based provider. Its target customers include private, business, school and public authorities.