Silent Circle is an encrypted communications firm based in

Washington DC Washington, D.C., formally the District of Columbia and commonly known as Washington or D.C., is the capital city and Federal district of the United States, federal district of the United States. The city is on the Potomac River, across from ...

. Silent Circle provides multi-platform

secure communication Secure communication is when two entities are communicating and do not want a third party to listen in. For this to be the case, the entities need to communicate in a way that is unsusceptible to eavesdropping or interception. Secure communication ...

services for mobile devices and desktops. Launched October 16, 2012, the company operates under a

subscription business model The subscription business model is a business model in which a customer must pay a recurring price at regular intervals for access to a product or service. The model was pioneered by publishers of books and periodicals in the 17th century. It ...

. The encryption part of the software used is

free software Free software, libre software, libreware sometimes known as freedom-respecting software is computer software distributed open-source license, under terms that allow users to run the software for any purpose as well as to study, change, distribut ...

open source Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use and view the source code, design documents, or content of the product. The open source model is a decentrali ...

and peer-reviewed. For the remaining parts of Silent Phone and Silent Text, the

source code In computing, source code, or simply code or source, is a plain text computer program written in a programming language. A programmer writes the human readable source code to control the behavior of a computer. Since a computer, at base, only ...

is available on

GitHub GitHub () is a Proprietary software, proprietary developer platform that allows developers to create, store, manage, and share their code. It uses Git to provide distributed version control and GitHub itself provides access control, bug trackin ...

, but under

proprietary software Proprietary software is computer software, software that grants its creator, publisher, or other rightsholder or rightsholder partner a legal monopoly by modern copyright and intellectual property law to exclude the recipient from freely sharing t ...

licenses.

History

In November 2011, Mike Janke called

Phil Zimmermann Philip R. Zimmermann (born 1954) is an American computer scientist and cryptographer. He is the creator of Pretty Good Privacy (PGP), the most widely used email encryption software in the world. He is also known for his work in VoIP encryption ...

with an idea for a new kind of private, secure version of

Skype Skype () was a proprietary telecommunications application operated by Skype Technologies, a division of Microsoft, best known for IP-based videotelephony, videoconferencing and voice calls. It also had instant messaging, file transfer, ...

. Zimmermann agreed to the project and called

Jon Callas Jon Callas is an American computer security expert, software engineer, user experience designer, and technologist who is the co-founder and former CTO of the global encrypted communications service Silent Circle.http://www.linkedin.com/in/joncal ...

, co-founder of

PGP Corporation PGP Corporation was a company that sold Pretty Good Privacy computer software. It was founded in 2002, and acquired by Symantec in 2010, and by Broadcom in 2019. History PGP Corporation was co-founded in June 2002 by Jon Callas and Phil Dunkel ...

and Vincent Moscaritolo. Janke brought in security expert Vic Hyder, and the founding team was established. The company was founded in the Caribbean island of

Nevis Nevis ( ) is an island in the Caribbean Sea that forms part of the inner arc of the Leeward Islands chain of the West Indies. Nevis and the neighbouring island of Saint Kitts constitute the Saint Kitts and Nevis, Federation of Saint Kitts ...

, but moved its headquarters to

Le Grand-Saconnex Le Grand-Saconnex () is a municipality of the Canton of Geneva, Switzerland. Several international organizations and permanent missions to the United Nations are located in Grand Saconnex. Consequently, the population of Grand Saconnex is quite ...

near Geneva, Switzerland in 2014 in search of a country with "stronger privacy laws to protect its customers' information." On August 9, 2013, through their website, Silent Circle announced that the Silent Mail service would be shut down, because the company could "see the writing on the wall" and felt it was not possible to sufficiently secure email data with the looming threat of government compulsion and precedent set by the

Lavabit Lavabit is an open-source encrypted webmail service, founded in 2004. The service suspended its operations on August 8, 2013, after the U.S. Federal Government ordered it to turn over its Secure Sockets Layer (SSL) private keys, in order to al ...

shutdown the day before. In January 2015, Silent Text had a serious vulnerability that allowed an attacker to remotely take control of a Blackphone device. A potential attacker only needed to know the target’s Silent Circle ID number or phone number. Blackphone and Silent Circle patched the vulnerability shortly after it had been disclosed. In March 2015 there was a controversy when

Information Security Information security is the practice of protecting information by mitigating information risks. It is part of information risk management. It typically involves preventing or reducing the probability of unauthorized or inappropriate access to data ...

specialist and

hacker A hacker is a person skilled in information technology who achieves goals and solves problems by non-standard means. The term has become associated in popular culture with a security hackersomeone with knowledge of bug (computing), bugs or exp ...

Khalil Sehnaoui identified that Silent Circle's

warrant canary A warrant canary is a method by which a communications service provider aims to implicitly inform its users that the provider has been served with a government subpoena despite legal prohibitions on revealing the existence of the subpoena. The wa ...

had been removed from their site. In January 2017 Gregg Smith was named CEO with a renewed focus on serving the large business space as well as Government entities. At the same time Tony Cole, VP and Global Government CTO of

FireEye Trellix (formerly FireEye and McAfee Enterprise) is a privately held cybersecurity company that was founded in 2022. It provides hardware, software, and services to investigate cybersecurity attacks, protect against malicious software, and ana ...

, was named to the Board of Directors. Shortly after Smith became CEO, the company moved back from Switzerland to the United States.

Reception

In November 2014, Silent Phone and Silent Text received top scores on the

Electronic Frontier Foundation The Electronic Frontier Foundation (EFF) is an American international non-profit digital rights group based in San Francisco, California. It was founded in 1990 to promote Internet civil liberties. It provides funds for legal defense in court, ...

's secure messaging scorecard, along with "

ChatSecure ChatSecure is a messaging application for iOS which allows OTR and OMEMO encryption for the XMPP protocol. ChatSecure is free and open source software available under the GPL-3.0-or-later license. ChatSecure has been used by international ind ...

Orbot Orbot is a free proxy app that provides anonymity on the Internet for users of the Android and iOS operating systems. It allows traffic from apps such as web browsers, email clients, map programs, and others to be routed via the Tor network ...

Cryptocat Cryptocat is a discontinued open-source software, open-source Application software, desktop application intended to allow encrypted online chatting available for Microsoft Windows, Windows, OS X, and Linux. It uses end-to-end encryption to secur ...

TextSecure TextSecure was an encrypted messaging application for Android that was developed from 2010 to 2015. It was a predecessor to Signal and the first application to use the Signal Protocol, which has since been implemented into WhatsApp and other app ...

, and "

Signal A signal is both the process and the result of transmission of data over some media accomplished by embedding some variation. Signals are important in multiple subject fields including signal processing, information theory and biology. In ...

RedPhone Open Whisper Systems (abbreviated OWS) was a software development group that was founded by Moxie Marlinspike in 2013. The group picked up the open source development of TextSecure and RedPhone, and was later responsible for starting the develo ...

". They received points for having communications encrypted in transit, having communications encrypted with keys the providers don't have access to (

end-to-end encryption End-to-end encryption (E2EE) is a method of implementing a secure communication system where only communicating users can participate. No one else, including the system provider, telecom providers, Internet providers or malicious actors, can ...

), making it possible for users to independently verify their correspondent's identities, having past communications secure if the keys are stolen (

forward secrecy In cryptography, forward secrecy (FS), also known as perfect forward secrecy (PFS), is a feature of specific key-agreement protocols that gives assurances that session keys will not be compromised even if long-term secrets used in the session ke ...

), having their code open to independent review (

), having their security designs well-documented, and having recent independent security audits. However, as of August 2020, the page for the secure messaging scorecard states that it is out of date and should not be used in privacy- and security-related decision-making.

Products

The company's products enable encrypted mobile phone calls, text messaging, and video chat.

Current

Its current products include the following: *Silent Phone: Encrypted voice calls, video calls and text messages on mobile devices. Currently available for iOS, Android, and Silent Circle’s Silent OS on Blackphone. It can be used with Wi-Fi, EDGE, 3G or 4G cellular anywhere in the world.

Discontinued

Its discontinued products include the following: *

Blackphone The Blackphone was a smartphone built to ensure privacy, developed by SGP Technologies, a wholly owned subsidiary of Silent Circle. Originally, SGP Technologies was a joint venture between the makers of GeeksPhone and Silent Circle. Marketing i ...

: A smartphone designed for privacy created by Silent Circle and built by SGP Technologies, a joint venture between Silent Circle and

Geeksphone GeeksPhone was a Spanish smartphone company founded in 2009. GeeksPhone's most notable products are open Android phones and developer devices of Firefox OS. History GeeksPhone was founded in early 2009 by Javier Agüera and Rodrigo Silva-Ramos. ...

. There have been no more news or updates since 2018. PrivatOS was Discontinued on June 30, 2016. *GoSilent: Personal Firewall with integrated

VPN Virtual private network (VPN) is a network architecture for virtually extending a private network (i.e. any computer network which is not the public Internet) across one or multiple other networks which are either untrusted (as they are not c ...

and

Cloud Analytics Cloud analytics is a marketing term for businesses to carry out analysis using cloud computing. It uses a range of analytical tools and techniques to help companies extract information from massive data and present it in a way that is easily catego ...

. The product was introduced after Silent Circle acquired Maryland start-up Kesala. It was sold by Silent Circle's new owner in 2018 *Silent Text: Discontinued September 28, 2015. A stand-alone application for encrypted text messaging and secure cloud content transfer with a “burn notice” feature for permanently deleting messages from devices. Its features were merged into Silent Phone. *Silent Mail: Discontinued August 9, 2013. Silent Mail used to offer encrypted email on Silent Circle’s private, secure network and compatibility with popular email client software.

Silent Circle Instant Message Protocol

Silent Circle Instant Message Protocol (SCIMP) was an encryption scheme that was developed by Vincent Moscaritolo. It enabled private conversation over instant message transports such as

XMPP Extensible Messaging and Presence Protocol (abbreviation XMPP, originally named Jabber) is an Open standard, open communication protocol designed for instant messaging (IM), presence information, and contact list maintenance. Based on XML (Ext ...

(Jabber). SCIMP provided encryption, perfect

and message authentication. It also handled negotiating the shared secret keys.

History

The protocol was used in Silent Text. Silent Text was discontinued on September 28, 2015, when its features were merged into Silent Circle's encrypted voice calling application called Silent Phone. At the same time, Silent Circle transitioned to using a protocol that uses the

Double Ratchet Algorithm In cryptography, the Double Ratchet Algorithm (previously referred to as the Axolotl Ratchet) is a key management algorithm that was developed by Trevor Perrin and Moxie Marlinspike in 2013. It can be used as part of a cryptographic protocol t ...

instead of SCIMP.

Business model

The company is privately funded and operates under a

References

External links

*{{Official website, https://www.silentcircle.com/ Cryptographic software Cryptography companies Swiss brands

History

Reception

Products

Current

Discontinued

Silent Circle Instant Message Protocol

History

Business model

See also

References

Further reading

External links