Jump to content

Telegram (software): Difference between revisions

From Wikipedia, the free encyclopedia
Browse history interactively
← Previous editNext edit →
Content deleted Content added
VisualWikitext
JudgeGregg (talk | contribs)
252 edits
This is reflected in the Reception section. Rm as per MOS:INTRO. Relative emphasis in reliable sources doesn't warrant a mention at top.
(10 intermediate revisions by 4 users not shown)
Line 19: Line 19:
}}
}}


'''Telegram''' is a [[Cloud computing|cloud]]-based [[instant messaging]] service. Telegram [[client (computing)|clients]] exist for both mobile ([[Android (operating system)|Android]], [[iOS]], [[Windows Phone]], [[Ubuntu Touch]]) and desktop systems ([[Microsoft Windows|Windows]], [[OS X]], [[Linux]]).<ref name="teleapps">{{cite web|url=https://telegram.org/apps|title=List of Telegram applications|date=6 February 2014}}</ref><ref>{{cite web|url=http://www.squer.it/of/cosa-e-telegram-messenger/|title=Che cosa è Telegram, Squer.it|language=it}}</ref> Users can send messages and exchange photos, videos, stickers and files of any type up to 1.5 GB in size. Telegram also provides optional [[End-to-end encryption|end-to-end encrypted]] messaging with self-destruct timers.
'''Telegram''' is a [[Cloud computing|cloud]]-based [[instant messaging]] service. Telegram [[client (computing)|clients]] exist for both mobile ([[Android (operating system)|Android]], [[iOS]], [[Windows Phone]], [[Ubuntu Touch]]) and desktop systems ([[Microsoft Windows|Windows]], [[OS X]], [[Linux]]).<ref name="teleapps">{{cite web|url=https://telegram.org/apps|title=List of Telegram applications|date=6 February 2014}}</ref><ref>{{cite web|url=http://www.squer.it/of/cosa-e-telegram-messenger/|title=Che cosa è Telegram, Squer.it|language=it}}</ref> Users can send messages and exchange photos, videos, stickers and files of any type. Telegram also provides optional [[End-to-end encryption|end-to-end encrypted]] messaging with self-destruct timers.


⚫
Telegram is supported by the [[Russians|Russian]]-born entrepreneur [[Pavel Durov]],<ref name="TelegramFAQ">{{cite web|url = https://telegram.org/faq#q-who-are-the-people-behind-telegram|title = Telegram FAQ|date = 9 August 2015}}</ref> who is now a citizen of [[Saint Kitts and Nevis]],<ref>{{Cite web|url = http://www.themoscowtimes.com/news/article/vkontakte-founder-pavel-durov-becomes-citizen-of-st-kitts-and-nevis/499038.html|title = Vkontakte Founder Pavel Durov Becomes Citizen of St. Kitts and Nevis|date = 28 April 2014|website = [[The Moscow Times]]|access-date = 1 March 2016}}</ref> travelling the world in self-imposed exile.<ref name=":0" /> Its client-side code is [[open-source software]], whereas its server-side code is closed-sourced and proprietary. The service also provides [[Application programming interface|APIs]] to independent developers.
The security features of Telegram have been strongly contested by the security community<ref name="unhandledexpression" /><ref name="ferrari" />, comparing Telegram to "[[snake oil]]"<ref name="moxie">{{cite web|last1=Marlinspike|first1=Moxie|title=A Crypto Challenge For The Telegram Developers|url=http://www.thoughtcrime.org/blog/telegram-crypto-challenge/|accessdate=16 March 2016|date=2013-12-19}}</ref>, because of its vulnerability to [[Man-in-the-middle attack|man-in-the-middle attacks]] and privacy intrusions.<ref name="ferrari" />

⚫
Telegram is supported by the [[Russians|Russian]]-born entrepreneur [[Pavel Durov]],<ref name="TelegramFAQ">{{cite web|url = https://telegram.org/faq#q-who-are-the-people-behind-telegram|title = Telegram FAQ|date = 9 August 2015}}</ref> who is now living in [[Saint Kitts and Nevis]],<ref>{{Cite web|url = http://www.themoscowtimes.com/news/article/vkontakte-founder-pavel-durov-becomes-citizen-of-st-kitts-and-nevis/499038.html|title = Vkontakte Founder Pavel Durov Becomes Citizen of St. Kitts and Nevis|date = 28 April 2014|website = [[The Moscow Times]]|access-date = 1 March 2016}}</ref> in self-imposed exile.<ref name=":0" /> He founded the Russian [[Social networking service|social network]] [[VK (social networking)|VK]] and was its [[Chief executive officer|CEO]] until April 2014. Its client-side code is [[open-source software]] in parts, whereas its server-side code is closed-sourced and proprietary. The service also provides [[Application programming interface|APIs]] to independent developers.


== History ==
== History ==


=== Development ===
=== Development ===
Telegram was launched in 2013 by brothers [[Nikolai Durov|Nikolai]] and [[Pavel Durov]], who previously founded the [[Russia]]n social network [[VK (social network)|VK]], but had to leave the company after it was taken over by the Russian Government.<ref name=":0" /><ref name="TechCrunch">{{cite web|url=http://techcrunch.com/2013/10/27/meet-telegram-a-secure-messaging-app-from-the-founders-of-vk-russias-largest-social-network/|title=Meet Telegram, A Secure Messaging App From The Founders Of VK, Russia’s Largest Social Network|publisher=TechCrunch|date=27 October 2013}}</ref> Nikolai Durov created the [[MTProto]] protocol that is the basis for the messenger, while Pavel provided financial support and infrastructure through his [[Axel Neff#Digital Fortress LLC|Digital Fortress]] fund. [[Axel Neff]] served as co-founder and CIO.<ref>{{cite web|url=http://www.reuters.com/article/2013/08/30/idUS74722569420130830|publisher=Reuters|title=Russia’s Zuckerberg launches Telegram, a new instant messenger service|date=30 August 2013}}</ref>
Telegram was launched in 2013 by brothers [[Nikolai Durov|Nikolai]] and [[Pavel Durov]], who previously founded the [[Russia]]n social network [[VK (social network)|VK]], but had to leave the company after it was taken over by the Russian Government.<ref name=":0" /><ref name="TechCrunch">{{cite web|url=http://techcrunch.com/2013/10/27/meet-telegram-a-secure-messaging-app-from-the-founders-of-vk-russias-largest-social-network/|title=Meet Telegram, A Secure Messaging App From The Founders Of VK, Russia’s Largest Social Network|publisher=TechCrunch|date=27 October 2013}}</ref> Nikolai Durov created the [[MTProto]] protocol that is the basis for the messenger, while Pavel provided financial support and infrastructure through his [[Axel Neff#Digital Fortress LLC|Digital Fortress]] fund.<ref>{{cite web|url=http://www.reuters.com/article/2013/08/30/idUS74722569420130830|publisher=Reuters|title=Russia’s Zuckerberg launches Telegram, a new instant messenger service|date=30 August 2013}}</ref>


Telegram is registered as both an English [[Limited liability partnership|LLP]]<ref>{{Cite web|title = Telegram - Android Apps on Google Play|url = https://play.google.com/store/apps/details?id=org.telegram.messenger|website = play.google.com|accessdate = 2015-11-19}}</ref> and an American [[Limited liability company|LLC]].<ref>{{Cite web|title = Telegram Messenger on the App Store|url = https://itunes.apple.com/app/telegram-messenger/id686449807|website = App Store|accessdate = 2015-11-19}}</ref> It does not disclose where it rents offices or which legal entities it uses to rent them, citing the need to "shelter the team from unnecessary influence" and protect users from governmental data requests.<ref>{{Cite news|title = Lunch with the FT: Pavel Durov|url = http://www.ft.com/cms/s/0/21c5c7f2-20b1-11e5-ab0f-6bb9974f25d0.html|newspaper = [[Financial Times]]|access-date = 19 November 2015|first = John|last = Thornhill|date = 3 July 2015}}</ref> The service says that it is headquartered in [[Berlin]], [[Germany]].<ref name="TheVergeKorea">{{cite web|url = http://www.theverge.com/2014/10/6/6926205/surveillance-drives-south-koreans-to-encrypted-messaging-apps|title = Surveillance drives South Koreans to encrypted messaging apps|date = 6 October 2014|website = [[The Verge]]|accessdate = 19 November 2015|first = Russell|last = Brandom}}</ref> Durov left Russia and is said to be moving from country to country with a small group of computer programmers.<ref name=":0">{{Cite news|title = Once Celebrated in Russia, the Programmer Pavel Durov Chooses Exile|url = http://www.nytimes.com/2014/12/03/technology/once-celebrated-in-russia-programmer-pavel-durov-chooses-exile.html|newspaper = [[The New York Times]]|date = 2 December 2014|access-date = 19 November 2015|first = Danny|last = Hakim}}</ref>
Telegram is registered as both an English [[Limited liability partnership|LLP]]<ref>{{Cite web|title = Telegram - Android Apps on Google Play|url = https://play.google.com/store/apps/details?id=org.telegram.messenger|website = play.google.com|accessdate = 2015-11-19}}</ref> and an American [[Limited liability company|LLC]].<ref>{{Cite web|title = Telegram Messenger on the App Store|url = https://itunes.apple.com/app/telegram-messenger/id686449807|website = App Store|accessdate = 2015-11-19}}</ref> It does not disclose where it rents offices or which legal entities it uses to rent them, citing the need to "shelter the team from unnecessary influence" and protect users from governmental data requests.<ref>{{Cite news|title = Lunch with the FT: Pavel Durov|url = http://www.ft.com/cms/s/0/21c5c7f2-20b1-11e5-ab0f-6bb9974f25d0.html|newspaper = [[Financial Times]]|access-date = 19 November 2015|first = John|last = Thornhill|date = 3 July 2015}}</ref> The service says that it is headquartered in [[Berlin]], [[Germany]].<ref name="TheVergeKorea">{{cite web|url = http://www.theverge.com/2014/10/6/6926205/surveillance-drives-south-koreans-to-encrypted-messaging-apps|title = Surveillance drives South Koreans to encrypted messaging apps|date = 6 October 2014|website = [[The Verge]]|accessdate = 19 November 2015|first = Russell|last = Brandom}}</ref> Durov left Russia and is said to be moving from country to country with a small group of computer programmers.<ref name=":0">{{Cite news|title = Once Celebrated in Russia, the Programmer Pavel Durov Chooses Exile|url = http://www.nytimes.com/2014/12/03/technology/once-celebrated-in-russia-programmer-pavel-durov-chooses-exile.html|newspaper = [[The New York Times]]|date = 2 December 2014|access-date = 19 November 2015|first = Danny|last = Hakim}}</ref>

In September 2015, [[Samsung]] released a new messaging application based on Telegram Messenger.<ref>{{cite web|url =http://news.samsung.com/global/socializer-messenger-app-offers-a-new-approach-to-messaging|title = Socializer Messenger App Offers a New Approach to Messaging|date = 14 September 2015}}</ref>


=== Usage numbers ===
=== Usage numbers ===
Line 54: Line 50:


=== Account ===
=== Account ===
Similar to services like [[WhatsApp]], Telegram accounts are tied to telephone numbers and verified by [[Short Message Service|SMS]] or phone call.<ref name="Lopez">{{Citation|url=http://www.applesfera.com/aplicaciones-ios-1/configurando-telegram-en-el-iphone-en-la-web-y-en-el-mac|title=Configurando Telegram en el iPhone, en la web y en el Mac|first=Miguel|last=Lopez|trans_title=Configuring Telegram in the Apple iPhone, the Web and the Mac|language=es|publisher=Applesfera|accessdate=4 December 2014}}</ref> Users can add multiple devices to their account and receive messages on each one. Connected devices can be removed individually or all at once. The associated number can be changed at any time and when doing so, the user's contacts will receive the new number automatically.<ref name="Lopez" /><ref name="way-transf">{{cite web|url = http://www.wayerless.com/2014/12/telegram-se-actualiza-permitiendo-ahora-migrar-tus-conversaciones-y-contactos-a-una-linea-nueva/|first = Jonathan|last = Munizaga|date = 1 December 2014|trans_title = Telegram already allows migrating conversations and contacts to a new line|title = Telegram ya permite migrar conversaciones y contactos a una línea nueva|publisher = Wayerless|accessdate = 2 December 2014|language = es}}</ref><ref name="te-transf">{{cite web|language = es|url = http://www.tuexpertoapps.com/2014/12/02/telegram-ahora-permite-traspasar-mensajes-al-cambiar-de-numero/|first = David G|last = Mateo|date = 1 December 2014|title = Telegram ahora permite traspasar mensajes al cambiar de número|publisher = TuExperto|accessdate = 2 December 2014}}</ref> In addition, a user can set up an [[Pseudonym|alias]] that allows them to send and receive messages without exposing their phone number.<ref name="cs2.0">{{cite web|url=http://techcrunch.com/2014/10/23/secure-messaging-app-telegram-adds-usernames-and-snapchat-like-hold-to-view-for-media/|title=Secure Messaging App Telegram Adds Usernames And Snapchat-Like Hold-To-View For Media|publisher=Techcrunch|date=23 October 2014|accessdate=23 October 2014}}</ref> These aliases or usernames are also linked with an official <nowiki>https://telegram.me/</nowiki><alias> [[URLs|URL]] (where <alias> is the chosen username). Usernames can be changed at any time. Accounts can be deleted at any time and they are deleted automatically after six months of inactivity by default, which can optionally be changed to 1 to 12 months. Users can replace exact "last seen" timestamps with fudged messages such as "last seen within a week".<ref>{{cite news|last1=Riggall|first1=Jon|title=Telegram for iOS and Android gets new privacy features|url=http://news.en.softonic.com/telegram-for-ios-and-android-gets-new-privacy-features|work=Softonic|date=19 November 2014}}</ref>
Similar to services like [[WhatsApp]], Telegram accounts are tied to telephone numbers and are verified by [[Short Message Service|SMS]] or phone call.<ref name="Lopez">{{Citation|url=http://www.applesfera.com/aplicaciones-ios-1/configurando-telegram-en-el-iphone-en-la-web-y-en-el-mac|title=Configurando Telegram en el iPhone, en la web y en el Mac|first=Miguel|last=Lopez|trans_title=Configuring Telegram in the Apple iPhone, the Web and the Mac|language=es|publisher=Applesfera|accessdate=4 December 2014}}</ref> Users can add multiple devices to their account and receive messages on each one. Connected devices can be removed individually or all at once. The associated number can be changed at any time and when doing so, the user's contacts will receive the new number automatically.<ref name="Lopez" /><ref name="way-transf">{{cite web|url = http://www.wayerless.com/2014/12/telegram-se-actualiza-permitiendo-ahora-migrar-tus-conversaciones-y-contactos-a-una-linea-nueva/|first = Jonathan|last = Munizaga|date = 1 December 2014|trans_title = Telegram already allows migrating conversations and contacts to a new line|title = Telegram ya permite migrar conversaciones y contactos a una línea nueva|publisher = Wayerless|accessdate = 2 December 2014|language = es}}</ref><ref name="te-transf">{{cite web|language = es|url = http://www.tuexpertoapps.com/2014/12/02/telegram-ahora-permite-traspasar-mensajes-al-cambiar-de-numero/|first = David G|last = Mateo|date = 1 December 2014|title = Telegram ahora permite traspasar mensajes al cambiar de número|publisher = TuExperto|accessdate = 2 December 2014}}</ref> In addition, a user can set up an [[Pseudonym|alias]] that allows them to send and receive messages without exposing their phone number.<ref name="cs2.0">{{cite web|url=http://techcrunch.com/2014/10/23/secure-messaging-app-telegram-adds-usernames-and-snapchat-like-hold-to-view-for-media/|title=Secure Messaging App Telegram Adds Usernames And Snapchat-Like Hold-To-View For Media|publisher=Techcrunch|date=23 October 2014|accessdate=23 October 2014}}</ref> Accounts can be deleted at any time and they are deleted automatically after six months of inactivity by default, which can optionally be changed to 1 to 12 months. Users can replace exact "last seen" timestamps with fudged messages such as "last seen within a week".<ref>{{cite news|last1=Riggall|first1=Jon|title=Telegram for iOS and Android gets new privacy features|url=http://news.en.softonic.com/telegram-for-ios-and-android-gets-new-privacy-features|work=Softonic|date=19 November 2014}}</ref>


=== Cloud-based messages ===
=== Cloud-based messages ===
Line 70: Line 66:
=== Secret chats ===
=== Secret chats ===
[[File:Telegram secret chat - en.png|thumb|200px|A "secret chat" confirmation notice - screenshot from [[Android Marshmallow]].]]
[[File:Telegram secret chat - en.png|thumb|200px|A "secret chat" confirmation notice - screenshot from [[Android Marshmallow]].]]
Messages can also be sent with client-to-client encryption in so-called secret chats that are not cloud-based. Secret chat messages are encrypted with the service's MTProto protocol.<ref name="techfaq" /> Contrary to Telegram's cloud-based messages, messages sent within a secret chat can be accessed only on the devices upon which the secret chat was initiated or accepted; they can't be accessed on other devices.<ref name="TechCrunch" /><ref name="how-secure">{{Citation|url=https://telegram.org/faq#q-how-secure-is-telegram|publisher=Telegram|work=FAQ|title=How secure is Telegram?}}</ref><ref>{{Citation|publisher=Telegram|url=https://core.telegram.org/mtproto|title=Description of MTProto Mobile Protocol}}</ref>
Messages can also be sent with client-to-client encryption in so-called secret chats. These messages are encrypted with the service's MTProto protocol.<ref name="techfaq" /> Contrary to Telegram's cloud-based messages, messages sent within a secret chat can be accessed only on the device upon which the secret chat was initiated and the device upon which the secret chat was accepted; they cannot be accessed on other devices.<ref name="TechCrunch" /><ref name="how-secure">{{Citation|url=https://telegram.org/faq#q-how-secure-is-telegram|publisher=Telegram|work=FAQ|title=How secure is Telegram?}}</ref><ref>{{Citation|publisher=Telegram|url=https://core.telegram.org/mtproto|title=Description of MTProto Mobile Protocol}}</ref>


Secret chats have to be initiated and accepted by an invitation, upon which the encryption keys for the session are exchanged. Messages sent within secret chats can, in principle, be deleted at any time and can optionally self-destruct.<ref>{{cite web|title=Telegram FAQ|url=https://telegram.org/faq#security|date=n.d.|accessdate=10 February 2014}}</ref> Some Telegram clients also allow users to encrypt the local message database using a passphrase.<ref name="zimperium">{{cite news|last1=Franceschi-Bicchierai|first1=Lorenzo|title=Encryption Fails: When to Freak Out and When to Chill|url=http://motherboard.vice.com/read/encryption-fails-when-to-freak-out-and-when-to-chill|work=VICE Motherboard|date=24 February 2015|accessdate=9 January 2016}}</ref>
Secret chats have to be initiated and accepted by an invitation, upon which the encryption keys for the session are exchanged. Messages sent within secret chats can, in principle, be deleted at any time and can optionally self-destruct.<ref>{{cite web|title=Telegram FAQ|url=https://telegram.org/faq#security|date=n.d.|accessdate=10 February 2014}}</ref> Some Telegram clients also allow users to encrypt the local message database using a passphrase.<ref name="zimperium">{{cite news|last1=Franceschi-Bicchierai|first1=Lorenzo|title=Encryption Fails: When to Freak Out and When to Chill|url=http://motherboard.vice.com/read/encryption-fails-when-to-freak-out-and-when-to-chill|work=VICE Motherboard|date=24 February 2015|accessdate=9 January 2016}}</ref>
Line 83: Line 79:


Since 2013,<ref>{{cite web|url=https://news.ycombinator.com/item?id=6913456 |title=Hacker News: Telegram – secure, free messaging|date=|accessdate=11 December 2015}}</ref> cryptography experts have expressed both doubts and criticisms on the MTProto encryption scheme, saying that deploying [[Snake oil (cryptography)|home-brewed and unproven cryptography]] may render the encryption vulnerable to bugs that potentially undermine its security, due to a lack of scrutiny.<ref name="Jakobsen-2015"/><ref name="Cox-2015">{{cite web|last1=Cox|first1=Joseph|title=Why You Don't Roll Your Own Crypto|url=http://motherboard.vice.com/read/why-you-dont-roll-your-own-crypto|website=Motherboard|publisher=Vice Media LLC|accessdate=11 December 2015|date=10 December 2015}}</ref> It has also been suggested that Telegram did not employ developers with sufficient expertise or credibility in this field.<ref>{{cite web|last1=Turton|first1=William|title=Cryptography expert casts doubt on encryption in ISIS' favorite messaging app|url=http://www.dailydot.com/politics/telegram-isis-encryption-cryptography/|website=The Daily Dot|accessdate=11 December 2015|date=19 November 2015}}</ref>
Since 2013,<ref>{{cite web|url=https://news.ycombinator.com/item?id=6913456 |title=Hacker News: Telegram – secure, free messaging|date=|accessdate=11 December 2015}}</ref> cryptography experts have expressed both doubts and criticisms on the MTProto encryption scheme, saying that deploying [[Snake oil (cryptography)|home-brewed and unproven cryptography]] may render the encryption vulnerable to bugs that potentially undermine its security, due to a lack of scrutiny.<ref name="Jakobsen-2015"/><ref name="Cox-2015">{{cite web|last1=Cox|first1=Joseph|title=Why You Don't Roll Your Own Crypto|url=http://motherboard.vice.com/read/why-you-dont-roll-your-own-crypto|website=Motherboard|publisher=Vice Media LLC|accessdate=11 December 2015|date=10 December 2015}}</ref> It has also been suggested that Telegram did not employ developers with sufficient expertise or credibility in this field.<ref>{{cite web|last1=Turton|first1=William|title=Cryptography expert casts doubt on encryption in ISIS' favorite messaging app|url=http://www.dailydot.com/politics/telegram-isis-encryption-cryptography/|website=The Daily Dot|accessdate=11 December 2015|date=19 November 2015}}</ref>

A [[Debian]] developer has raised concerns over privacy issues related to the Android Telegram application, that appears to transmit all the phone's contacts to Telegram's servers without the user's consent. He furthermore stated that encryption between contacts is not enabled by default, and no check on the public key material is performed when an encrypted conversation is started.<ref name=ferrari>{{cite web|last1=Ferrari|first1=Martín|title=Telegram|url=https://blog.tincho.org/posts/Telegram/|website=How to recognise different types of trees|accessdate=16 March 2016|date=2014-04-02}}</ref> In fact, no authentication of contacts is performed in Telegram, which means that [[Man-in-the-middle_attack|man in the middle attacks]] can be performed by the Telegram server.<ref name="unhandledexpression">{{cite web|title=Telegram, AKA “Stand back, we have Math PhDs!”|url=http://unhandledexpression.com/2013/12/17/telegram-stand-back-we-know-maths/|website=Unhandled expression|accessdate=16 March 2016|date=2013-12-18|first1=Geoffroy|last1=Couprie}}</ref>


In December 2015, two researchers from [[Aarhus University]] published a report in which they demonstrated that MTProto does not achieve [[Ciphertext indistinguishability#Indistinguishability under chosen ciphertext attack.2Fadaptive chosen ciphertext attack .28IND-CCA1.2C IND-CCA2.29|indistinguishability under chosen-ciphertext attack]] (IND-CCA) or [[authenticated encryption]].<ref name="Jakobsen-2015">{{cite web|last1=Jakobsen|first1=Jakob|last2=Orlandi|first2=Claudio|title=On the CCA (in)security of MTProto|website=Cryptology ePrint Archive|publisher=International Association for Cryptologic Research|date=8 December 2015|url=https://eprint.iacr.org/2015/1177.pdf|format=PDF|accessdate=11 December 2015}}</ref> The former means that it is possible to turn any ciphertext into a different ciphertext that decrypts to the same message. The researchers stressed that the attack was of a theoretical nature and they "did not see any way of turning the attack into a full plaintext-recovery attack".<ref name="Jakobsen-2015"/>
In December 2015, two researchers from [[Aarhus University]] published a report in which they demonstrated that MTProto does not achieve [[Ciphertext indistinguishability#Indistinguishability under chosen ciphertext attack.2Fadaptive chosen ciphertext attack .28IND-CCA1.2C IND-CCA2.29|indistinguishability under chosen-ciphertext attack]] (IND-CCA) or [[authenticated encryption]].<ref name="Jakobsen-2015">{{cite web|last1=Jakobsen|first1=Jakob|last2=Orlandi|first2=Claudio|title=On the CCA (in)security of MTProto|website=Cryptology ePrint Archive|publisher=International Association for Cryptologic Research|date=8 December 2015|url=https://eprint.iacr.org/2015/1177.pdf|format=PDF|accessdate=11 December 2015}}</ref> The former means that it is possible to turn any ciphertext into a different ciphertext that decrypts to the same message. The researchers stressed that the attack was of a theoretical nature and they "did not see any way of turning the attack into a full plaintext-recovery attack".<ref name="Jakobsen-2015"/>
Line 91: Line 85:
Telegram Messenger LLP has servers in a number of countries throughout the world to improve the response time of their service.<ref>{{cite web|trans_title=Telegram, the chat that competes with WhatsApp|place=[[Uruguay|UY]]|url=http://www.elpais.com.uy/vida-actual/que-telegram-chat-que-compite.html|work=El País|title=Telegram, el chat que compite con Whatsapp|language=es|accessdate=8 January 2016}}</ref> Telegram's server-side software is closed-source and proprietary. Pavel Durov has said that it would require a major architectural redesign of the server-side software to connect independent servers to the Telegram cloud.<ref>{{cite web|title = Pavel Durov, creador de Telegram: "Ninguna aplicación es 100% segura"|url = http://www.eldiario.es/turing/moviles_y_tabletas/telegram-pavel_durov-entrevista-app-movil-seguridad_0_224677688.html|work = eldiario.es|date = 2 February 2014|accessdate = 12 February 2014|trans-title = Pavel Durov, creator of Telegram: "No application is 100% safe"|last = Rull|first = Antonio|language = es}}</ref>
Telegram Messenger LLP has servers in a number of countries throughout the world to improve the response time of their service.<ref>{{cite web|trans_title=Telegram, the chat that competes with WhatsApp|place=[[Uruguay|UY]]|url=http://www.elpais.com.uy/vida-actual/que-telegram-chat-que-compite.html|work=El País|title=Telegram, el chat que compite con Whatsapp|language=es|accessdate=8 January 2016}}</ref> Telegram's server-side software is closed-source and proprietary. Pavel Durov has said that it would require a major architectural redesign of the server-side software to connect independent servers to the Telegram cloud.<ref>{{cite web|title = Pavel Durov, creador de Telegram: "Ninguna aplicación es 100% segura"|url = http://www.eldiario.es/turing/moviles_y_tabletas/telegram-pavel_durov-entrevista-app-movil-seguridad_0_224677688.html|work = eldiario.es|date = 2 February 2014|accessdate = 12 February 2014|trans-title = Pavel Durov, creator of Telegram: "No application is 100% safe"|last = Rull|first = Antonio|language = es}}</ref>


=== List of client applications ===
=== Client applications ===
Telegram has various clients. This list includes versions developed on official platforms backed by Telegram Messenger LLP and unofficial clients that are developed by the community. The source code of all official Telegram clients (and some of the unofficial clients) is [[open source]] and released under the [[GNU General Public License|GNU General Public Licence]] {{Nowrap|version 2}} or 3.
Telegram has various clients. This list includes versions developed on official platforms backed by Telegram Messenger LLP and unofficial clients that are developed by the community. The source code of all official Telegram clients (and some of the unofficial clients) is [[open source]] and released under the [[GNU General Public License|GNU General Public Licence]] {{Nowrap|version 2}} or 3.


Line 121: Line 115:
|}
|}
Users can also access Telegram's cloud-based messages via an official [[web browser]] interface called Telegram Web (aka Webogram). Users can share images, files and [[emoticon]]s with previously-added contacts; this works in most modern browsers, such as [[Firefox]], [[Safari (web browser)|Safari]], and [[Google Chrome]].<ref name=Apps /><ref name="gh-webogram" />
Users can also access Telegram's cloud-based messages via an official [[web browser]] interface called Telegram Web (aka Webogram). Users can share images, files and [[emoticon]]s with previously-added contacts; this works in most modern browsers, such as [[Firefox]], [[Safari (web browser)|Safari]], and [[Google Chrome]].<ref name=Apps /><ref name="gh-webogram" />

=== APIs ===
Telegram has public [[Application programming interface|APIs]] with which developers can access the same functionality as Telegram's official apps to build their own messaging applications.<ref>{{Cite news|url=http://www.programmableweb.com/news/can-telegram-beat-whatsapp-public-api/2014/03/03|title=Can Telegram Beat WhatsApp with a Public API?|last=Roble|first=Patricio|date=3 Mar 2014|work=ProgrammableWeb|access-date=|via=}}</ref> In February 2015, creators of the unofficial Whatsapp+ client released the Telegram Plus app after their original project got a [[Cease and desist|cease-and-desist order]] from [[WhatsApp]].<ref>{{Cite news|url=http://www.androidpolice.com/2015/02/27/whatsapp-developer-releases-telegram-forced-drop-first-project/|title=WhatsApp+ Developer Releases Telegram+ After Being Forced To Drop The First Project|last=King|first=Bertel|date=27 Feb 2015|work=AndroidPolice|access-date=|via=}}</ref><ref>{{Cite web|url=http://www.androidpolice.com/2015/01/21/whatsapp-now-officially-dead-receiving-cease-desist-real-whatsapp/|title=WhatsApp+ Is Now Officially Dead After Receiving A Cease And Desist From The Real WhatsApp|date=21 Jan 2015|website=Android Police|access-date=}}</ref> In September 2015, [[Samsung]] released a messaging application based on these APIs.<ref>{{cite web|url =http://news.samsung.com/global/socializer-messenger-app-offers-a-new-approach-to-messaging|title = Socializer Messenger App Offers a New Approach to Messaging|date = 14 September 2015}}</ref>

Telegram also offers an API that allows developers to create [[Software agent|bots]], which are accounts controlled by programs.<ref>{{Cite web|url=http://www.programmableweb.com/news/telegram-launches-bot-api-and-platform/2015/06/29|title=Telegram Launches Bot API and Platform|last=Carter|first=Eric|date=27 Jun 2015|website=ProgrammableWeb}}</ref><ref>{{Cite web|url=http://social.techcrunch.com/2015/06/24/telegrams-new-platform-lets-developers-create-smart-message-bots-with-multiple-uses/|title=Telegram’s New Platform Lets Developers Create Smart Message Bots With Multiple Uses|last=Butcher|first=Mike|date=24 Jun 2015|website=TechCrunch}}</ref> In February 2016, [[Forbes|''Forbes'']] launched an [[Artificial intelligence|AI]]-powered news bot that pushes popular stories to subscribers and replies to search queries with relevant articles.<ref>{{Cite web|url=http://www.forbes.com/sites/bruceupbin/2016/02/23/introducing-the-forbes-newsbot-on-telegram/#270d46ef3117|title=Introducing The Forbes Newsbot on Telegram|last=Ubpin|first=Bruce|date=23 Feb 2016|website=Forbes}}</ref> [[TechCrunch]] launched a similar bot in March 2016.<ref>{{Cite web|url=http://social.techcrunch.com/2016/03/15/check-out-the-new-ai-powered-techcrunch-news-bot-on-telegram-messenger/|title=Check out the new AI-powered TechCrunch news bot on Telegram messenger|last=Bernard|first=Travis|date=15 Mar 2016|website=TechCrunch}}</ref>


== Reception ==
== Reception ==


=== Security ===
=== Security ===

On 26 February 2014, the [[Germany|German]] [[Consumer organization|consumer organisation]] [[Stiftung Warentest]] had evaluated several data-protection aspects of Telegram, along with other popular instant-messaging clients. Among the aspects considered were: the security of the data transmission, the service's terms of use, the accessibility of the source code and the distribution of the app. Telegram was rated 'critical' (''{{Lang|de|kritisch}}'') overall. The organisation was favourable to Telegram's secure chats and partially open source code, but criticised the mandatory transfer of contact data to Telegram's server and the lack of an imprint or address on the service's website. It noted that while the message data is encrypted on the device, it could not analyse the transmission due to a lack of source code.<ref>{{Cite web|url=https://www.test.de/WhatsApp-und-Alternativen-Datenschutz-im-Test-4675013-0/|title=WhatsApp und Alternativen: Datenschutz im Test|date=26 February 2014|website=[[Stiftung Warentest]]|language=de|trans-title=WhatsApp and alternatives: data protection tested|access-date=2 March 2016}}</ref>
On 26 February 2014, the [[Germany|German]] [[Consumer organization|consumer organisation]] [[Stiftung Warentest]] had evaluated several data-protection aspects of Telegram, along with other popular instant-messaging clients. Among the aspects considered were: the security of the data transmission, the service's terms of use, the accessibility of the source code and the distribution of the app. Telegram was rated 'critical' (''{{Lang|de|kritisch}}'') overall. The organisation was favourable to Telegram's secure chats and partially open source code, but criticised the mandatory transfer of contact data to Telegram's servers and the lack of an imprint or address on the service's website. It noted that while the message data is encrypted on the device, it could not analyse the transmission due to a lack of source code.<ref>{{Cite web|url=https://www.test.de/WhatsApp-und-Alternativen-Datenschutz-im-Test-4675013-0/|title=WhatsApp und Alternativen: Datenschutz im Test|date=26 February 2014|website=[[Stiftung Warentest]]|language=de|trans-title=WhatsApp and alternatives: data protection tested|access-date=2 March 2016}}</ref>


The [[Electronic Frontier Foundation]] (EFF) has listed Telegram on its "Secure Messaging Scorecard". {{As of|2015|12|7}}, Telegram's default chat function has a score of 4 out of 7 points on the scorecard. It has received points for having communications encrypted in transit, having its code open to independent review, having the security design properly documented, and having completed an independent security audit. Telegram's default chat function is missing points because the communications are not encrypted with keys the provider doesn't have access to, users can't verify contacts' identities, and past messages are not secure if the encryption keys are stolen. Telegram's optional secret chat function, which provides end-to-end encryption, has a score of 7 out of 7 points on the scorecard.<ref>{{cite web|url = https://www.eff.org/secure-messaging-scorecard|title = Secure Messaging Scorecard|date = 27 February 2015|publisher = Electronic Frontier Foundation|accessdate = 7 December 2015}}</ref> An earlier version of the EFF's scorecard was criticized for being inaccurate, misleading and vague, but not specifically with regard to its evaluation of Telegram.<ref>{{Cite web|url = http://www.dailydot.com/politics/eff-secure-messaging-scorecard-critics/|title = The fight over EFF's Secure Messaging Scorecard|date = 5 November 2014|accessdate = 7 December 2015|website = [[The Daily Dot]]|last = Howell O'Neill|first = Patrick}}</ref>
The [[Electronic Frontier Foundation]] (EFF) has listed Telegram on its "Secure Messaging Scorecard". {{As of|2015|12|7}}, Telegram's default chat function has a score of 4 out of 7 points on the scorecard. It has received points for having communications encrypted in transit, having its code open to independent review, having the security design properly documented, and having completed an independent security audit. Telegram's default chat function is missing points because the communications are not encrypted with keys the provider doesn't have access to, users can't verify contacts' identities, and past messages are not secure if the encryption keys are stolen. Telegram's optional secret chat function, which provides end-to-end encryption, has a score of 7 out of 7 points on the scorecard.<ref>{{cite web|url = https://www.eff.org/secure-messaging-scorecard|title = Secure Messaging Scorecard|date = 27 February 2015|publisher = Electronic Frontier Foundation|accessdate = 7 December 2015}}</ref> An earlier version of the EFF's scorecard was criticized for being inaccurate, misleading and vague, but not specifically with regard to its evaluation of Telegram.<ref>{{Cite web|url = http://www.dailydot.com/politics/eff-secure-messaging-scorecard-critics/|title = The fight over EFF's Secure Messaging Scorecard|date = 5 November 2014|accessdate = 7 December 2015|website = [[The Daily Dot]]|last = Howell O'Neill|first = Patrick}}</ref>

Revision as of 16:34, 17 March 2016

Telegram
Developer(s)Telegram Messenger LLP
Initial releaseAugust 2013; 11 years ago (2013-08)
Stable release
Android11.4.0[1] Edit this on Wikidata / 17 November 2024; 4 days ago (17 November 2024)
iOS, iPadOS11.4[2] Edit this on Wikidata / 17 November 2024; 4 days ago (17 November 2024)
Windows, macOS, Linux
(Telegram Desktop)		5.8.0[3] Edit this on Wikidata / 17 November 2024; 4 days ago (17 November 2024)
macOS11.4[4] Edit this on Wikidata / 17 November 2024; 4 days ago (17 November 2024)
Repository
Operating systemAndroid, iOS, Windows Phone, Ubuntu Touch, Firefox OS, MS Windows, Linux, OS X
Available inEnglish, Arabic, Spanish, German, Italian, Korean, Dutch, Portuguese
TypeInstant messaging
License
Websitetelegram.org

Telegram is a cloud-based instant messaging service. Telegram clients exist for both mobile (Android, iOS, Windows Phone, Ubuntu Touch) and desktop systems (Windows, OS X, Linux).[5][7] Users can send messages and exchange photos, videos, stickers and files of any type. Telegram also provides optional end-to-end encrypted messaging with self-destruct timers.

Telegram is supported by the Russian-born entrepreneur Pavel Durov,[8] who is now a citizen of Saint Kitts and Nevis,[9] travelling the world in self-imposed exile.[10] Its client-side code is open-source software, whereas its server-side code is closed-sourced and proprietary. The service also provides APIs to independent developers.

History

Development

Telegram was launched in 2013 by brothers Nikolai and Pavel Durov, who previously founded the Russian social network VK, but had to leave the company after it was taken over by the Russian Government.[10][11] Nikolai Durov created the MTProto protocol that is the basis for the messenger, while Pavel provided financial support and infrastructure through his Digital Fortress fund.[12]

Telegram is registered as both an English LLP[13] and an American LLC.[14] It does not disclose where it rents offices or which legal entities it uses to rent them, citing the need to "shelter the team from unnecessary influence" and protect users from governmental data requests.[15] The service says that it is headquartered in Berlin, Germany.[16] Durov left Russia and is said to be moving from country to country with a small group of computer programmers.[10]

Usage numbers

In October 2013, Telegram had 100,000 daily active users.[11] On 24 March 2014, Telegram announced that it had reached 35 million monthly users and 15 million daily active users.[17] In October 2014, South Korean governmental surveillance plans drove many of its citizens to switch to Telegram.[16] In December 2014, Telegram announced they had 50 million active users, generating 1 billion daily messages and that they had 1 million new users signing up on their service every week;[18] traffic doubled in five months with 2 billion daily messages.[19] In September 2015, an announcement stated that the app had 60 million active users and delivered 12 billion daily messages.[20] In February 2016, Telegram announced that they had 100 million monthly active users, with 350.000 new users signing up every day, delivering 15 billion messages daily.[21]

Features

Account

Similar to services like WhatsApp, Telegram accounts are tied to telephone numbers and are verified by SMS or phone call.[22] Users can add multiple devices to their account and receive messages on each one. Connected devices can be removed individually or all at once. The associated number can be changed at any time and when doing so, the user's contacts will receive the new number automatically.[22][23][24] In addition, a user can set up an alias that allows them to send and receive messages without exposing their phone number.[25] Accounts can be deleted at any time and they are deleted automatically after six months of inactivity by default, which can optionally be changed to 1 to 12 months. Users can replace exact "last seen" timestamps with fudged messages such as "last seen within a week".[26]

Cloud-based messages

Telegram's default messages are cloud-based and can be accessed on any of the user's connected devices.[27] Users can share photos, videos, audio messages and other files (up to 1.5 gigabyte in size).[5][28] Users can send messages to other users individually or to groups of up to 1000 members.[29] The transmission of messages to Telegram Messenger LLP's servers is encrypted with the service's MTProto protocol.[27] According to Telegram's privacy policy, "all data is stored heavily encrypted and the encryption keys in each case are stored in several other DCs in different jurisdictions. This way local engineers or physical intruders cannot get access to user data".[30]

Bots

In June 2015, Telegram launched a platform for third-party developers to create bots.[31] Bots are Telegram accounts operated by programs. They can respond to messages or mentions, can be invited into groups and can be integrated into other programs. Dutch website Tweakers reported that an invited bot can potentially read all group messages when the bot controller changes the access settings silently at a later point in time. Telegram pointed out that it considered implementing a feature that would announce such a status change within the relevant group.[32]

Channels

Channels can be created for broadcasting messages to an unlimited number of subscribers.[33][34] Channels can be publicly available with an alias and a permanent URL so anyone can join. Users who join a channel can see the entire message history. Each message has its own view counter, showing how many users have seen this message. Users can join and leave channels at any time. Furthermore, users can mute a channel, meaning that the user will still receive messages, but won't be notified.

Stickers

Stickers are cloud-based, high-definition images intended to provide more expressive emoji. When typing in an emoji, the user is offered to send the respective sticker instead. Stickers come in collections called "sets", and multiple stickers can be offered for one emoji. Telegram comes with one default sticker set,[35] but users can install additional sticker sets provided by third-party contributors. Sticker sets installed from one client become automatically available to all other clients.

Secret chats

A "secret chat" confirmation notice - screenshot from Android Marshmallow.

Messages can also be sent with client-to-client encryption in so-called secret chats. These messages are encrypted with the service's MTProto protocol.[36] Contrary to Telegram's cloud-based messages, messages sent within a secret chat can be accessed only on the device upon which the secret chat was initiated and the device upon which the secret chat was accepted; they cannot be accessed on other devices.[11][27][37]

Secret chats have to be initiated and accepted by an invitation, upon which the encryption keys for the session are exchanged. Messages sent within secret chats can, in principle, be deleted at any time and can optionally self-destruct.[38] Some Telegram clients also allow users to encrypt the local message database using a passphrase.[39]

According to Telegram, secret chats have supported perfect forward secrecy since December 2014. Encryption keys are periodically changed after a key has been used more than 100 times or has been in use for more than a week. Old encryption keys are destroyed.[23][24][40]

Architecture

Encryption scheme

A simplified illustration of the MTProto encryption scheme.

Telegram uses a symmetric encryption scheme called MTProto. The protocol was developed by Nikolai Durov and other developers at Telegram and is based on 256-bit symmetric AES encryption, RSA 2048 encryption and Diffie–Hellman key exchange.[36]

Since 2013,[41] cryptography experts have expressed both doubts and criticisms on the MTProto encryption scheme, saying that deploying home-brewed and unproven cryptography may render the encryption vulnerable to bugs that potentially undermine its security, due to a lack of scrutiny.[42][43] It has also been suggested that Telegram did not employ developers with sufficient expertise or credibility in this field.[44]

In December 2015, two researchers from Aarhus University published a report in which they demonstrated that MTProto does not achieve indistinguishability under chosen-ciphertext attack (IND-CCA) or authenticated encryption.[42] The former means that it is possible to turn any ciphertext into a different ciphertext that decrypts to the same message. The researchers stressed that the attack was of a theoretical nature and they "did not see any way of turning the attack into a full plaintext-recovery attack".[42]

Servers

Telegram Messenger LLP has servers in a number of countries throughout the world to improve the response time of their service.[45] Telegram's server-side software is closed-source and proprietary. Pavel Durov has said that it would require a major architectural redesign of the server-side software to connect independent servers to the Telegram cloud.[46]

Client applications

Telegram has various clients. This list includes versions developed on official platforms backed by Telegram Messenger LLP and unofficial clients that are developed by the community. The source code of all official Telegram clients (and some of the unofficial clients) is open source and released under the GNU General Public Licence version 2 or 3.

Name Platform(s) Official Source code license Support for secret chats Notes
Telegram OS X Yes GPLv2[47] Yes
Telegram Desktop Microsoft Windows (portable application), OS X, and GNU/Linux Yes GPLv3 with OpenSSL exception[48] No
Cutegram Windows, OS X, and Linux No GPLv3[49] Yes Based on Qt.[50]
Telegram CLI Linux No[51] GPLv2[52] Yes Command-line interface for Telegram.
Telegram Messenger iOS 6 or later Yes GPLv2 or later[51][53] Yes Launched in August 2013 for iPhone and iPod Touch and relaunched in July 2014 with support for iPad.[54]
Telegram Android 2.3 or later Yes GPLv2 or later[51][55] Yes Supports tablets[56] and Android Wear smart watches.[57]
Telegram Messenger Windows Phone Yes GPLv2 or later[51] Yes
Telegram Firefox OS Yes GPLv3[58] No Based on Webogram.
Telegram Google Chrome and Chrome OS Yes GPLv3[58] No
Telegram Ubuntu Touch No GPLv2[59] Yes
Sailorgram Sailfish OS No GPLv3[60] Yes Based on Cutegram.

Users can also access Telegram's cloud-based messages via an official web browser interface called Telegram Web (aka Webogram). Users can share images, files and emoticons with previously-added contacts; this works in most modern browsers, such as Firefox, Safari, and Google Chrome.[51][58]

APIs

Telegram has public APIs with which developers can access the same functionality as Telegram's official apps to build their own messaging applications.[61] In February 2015, creators of the unofficial Whatsapp+ client released the Telegram Plus app after their original project got a cease-and-desist order from WhatsApp.[62][63] In September 2015, Samsung released a messaging application based on these APIs.[64]

Telegram also offers an API that allows developers to create bots, which are accounts controlled by programs.[65][66] In February 2016, Forbes launched an AI-powered news bot that pushes popular stories to subscribers and replies to search queries with relevant articles.[67] TechCrunch launched a similar bot in March 2016.[68]

Reception

Security

On 26 February 2014, the German consumer organisation Stiftung Warentest had evaluated several data-protection aspects of Telegram, along with other popular instant-messaging clients. Among the aspects considered were: the security of the data transmission, the service's terms of use, the accessibility of the source code and the distribution of the app. Telegram was rated 'critical' (kritisch) overall. The organisation was favourable to Telegram's secure chats and partially open source code, but criticised the mandatory transfer of contact data to Telegram's servers and the lack of an imprint or address on the service's website. It noted that while the message data is encrypted on the device, it could not analyse the transmission due to a lack of source code.[69]

The Electronic Frontier Foundation (EFF) has listed Telegram on its "Secure Messaging Scorecard". As of 7 December 2015, Telegram's default chat function has a score of 4 out of 7 points on the scorecard. It has received points for having communications encrypted in transit, having its code open to independent review, having the security design properly documented, and having completed an independent security audit. Telegram's default chat function is missing points because the communications are not encrypted with keys the provider doesn't have access to, users can't verify contacts' identities, and past messages are not secure if the encryption keys are stolen. Telegram's optional secret chat function, which provides end-to-end encryption, has a score of 7 out of 7 points on the scorecard.[70] An earlier version of the EFF's scorecard was criticized for being inaccurate, misleading and vague, but not specifically with regard to its evaluation of Telegram.[71]

Cryptography contests

Telegram has organised two cryptography contests to challenge third parties to break the service's cryptography and disclose the information contained within a secret chat between two fake users. A reward of respectively US$200,000 and US$300,000 was offered. Both of these contests expired with no winners.[72][73] Security researcher Moxie Marlinspike and commenters on Hacker News criticised the first contest for being rigged or framed in Telegram's favour and said that Telegram's statements on the value of these contests as proof of the cryptography's quality are misleading.[74][75][76]

Censorship

Telegram was open and working in Iran without any VPN or other circumvention methods in May 2015.[77] In August 2015, the Iranian Ministry of ICT asserted that Telegram had agreed to restrict some of its bots and sticker packs in Iran at the request of the Iranian government.[78] According to an article published on Global Voices, these features were being used by Iranians to "share porn and satirical comments about the Iranian government". The article also noted that "some users are concerned that Telegram's willingness to comply with Iranian government requests might mean future complicity with other Iranian government censorship, or even allow government access to Telegram's data on Iranian users".[78] However Telegram stated that all Telegram chats are private territory and that they do not process any requests related to them. Only requests regarding public content (bots and sticker packs) will be processed.[79]

Use by terrorists

In September 2015, in response to a question about the use of Telegram by extremists like ISIL, Pavel Durov stated: "I think that privacy, ultimately, and our right for privacy is more important than our fear of bad things happening, like terrorism."[80] ISIL has recommended Telegram to its supporters and members[81][82] and in October 2015 they were able to double the number of followers of their official channel to 9,000.[83] In November 2015, Telegram announced that it had blocked 78 public channels operated by ISIL, which were used for spreading propaganda and mass communication.[84][85] Telegram stated that it would block public channels and bots that are related to terrorism, but it would not honour "politically-motivated censorship" based on "local restrictions on freedom of speech" and that it allowed "[peaceful expression of] alternative opinions".[86] Telegram's usage for ISIL's propaganda has reignited the encryption debate and encrypted messaging applications have faced new scrutiny.[87][88]

See also

References

  1. ^ "Telegram". Google Play. Retrieved 17 November 2024.
  2. ^ "Telegram Messenger". App Store. Retrieved 17 November 2024.
  3. ^ "Releases v5.8.0". Retrieved 17 November 2024.
  4. ^ "Telegram for macOS". Retrieved 17 November 2024.
  5. ^ a b c "List of Telegram applications". 6 February 2014.
  6. ^ "Telegram.org Site Info". Alexa, Inc. Retrieved 6 March 2016.
  7. ^ "Che cosa è Telegram, Squer.it" (in Italian).
  8. ^ "Telegram FAQ". 9 August 2015.
  9. ^ "Vkontakte Founder Pavel Durov Becomes Citizen of St. Kitts and Nevis". The Moscow Times. 28 April 2014. Retrieved 1 March 2016.
  10. ^ a b c Hakim, Danny (2 December 2014). "Once Celebrated in Russia, the Programmer Pavel Durov Chooses Exile". The New York Times. Retrieved 19 November 2015.
  11. ^ a b c "Meet Telegram, A Secure Messaging App From The Founders Of VK, Russia's Largest Social Network". TechCrunch. 27 October 2013.
  12. ^ "Russia's Zuckerberg launches Telegram, a new instant messenger service". Reuters. 30 August 2013.
  13. ^ "Telegram - Android Apps on Google Play". play.google.com. Retrieved 19 November 2015.
  14. ^ "Telegram Messenger on the App Store". App Store. Retrieved 19 November 2015.
  15. ^ Thornhill, John (3 July 2015). "Lunch with the FT: Pavel Durov". Financial Times. Retrieved 19 November 2015.
  16. ^ a b Brandom, Russell (6 October 2014). "Surveillance drives South Koreans to encrypted messaging apps". The Verge. Retrieved 19 November 2015.
  17. ^ Telegram Hits 35M Monthly Users, 15M Daily With 8B Messages Received Over 30 Days, TechCrunch, 24 March 2014
  18. ^ Telegram Reaches 1 Billion Daily Messages, Telegram, 8 December 2014
  19. ^ Telegram Hits 2 Billion Messages Sent Daily, Telegram, 13 May 2015
  20. ^ Lomas, Natasha (21 September 2015). "Telegram Now Seeing 12BN Daily Messages, up From 1BN in February". Techcrunch. Retrieved 19 November 2015.
  21. ^ Burns, Matt (23 February 2016). "Encrypted Messaging App Telegram Hits 100M Monthly Active Users, 350k New Users Each Day". TechCrunch. Retrieved 23 February 2016.
  22. ^ a b Lopez, Miguel, Configurando Telegram en el iPhone, en la web y en el Mac (in Spanish), Applesfera, retrieved 4 December 2014 {{citation}}: Unknown parameter |trans_title= ignored (|trans-title= suggested) (help)
  23. ^ a b Munizaga, Jonathan (1 December 2014). "Telegram ya permite migrar conversaciones y contactos a una línea nueva" (in Spanish). Wayerless. Retrieved 2 December 2014. {{cite web}}: Unknown parameter |trans_title= ignored (|trans-title= suggested) (help)
  24. ^ a b Mateo, David G (1 December 2014). "Telegram ahora permite traspasar mensajes al cambiar de número" (in Spanish). TuExperto. Retrieved 2 December 2014.
  25. ^ "Secure Messaging App Telegram Adds Usernames And Snapchat-Like Hold-To-View For Media". Techcrunch. 23 October 2014. Retrieved 23 October 2014.
  26. ^ Riggall, Jon (19 November 2014). "Telegram for iOS and Android gets new privacy features". Softonic.
  27. ^ a b c "How secure is Telegram?", FAQ, Telegram
  28. ^ "Telegram: una alternativa gratuita a WhatsApp con ventajas y algún punto oscuro" (in Spanish). 1 March 2014. Retrieved 4 December 2014. {{cite web}}: Unknown parameter |trans_title= ignored (|trans-title= suggested) (help)
  29. ^ Novet, Jordan (25 November 2015). "Following ISIS crackdown, Telegram adds group admins, supergroups for up to 1K users". VentureBeat.
  30. ^ "Telegram Privacy Policy". Telegram. Retrieved 17 January 2016.
  31. ^ Telegram Bot Platform, Telegram, 24 June 2015, retrieved 1 September 2015
  32. ^ Schellevis, Joost (23 July 2015). "Telegram-bots kunnen relatief ongemerkt meelezen in groepsgesprekken". Tweakers (in Dutch). Retrieved 25 October 2015.
  33. ^ Channels, Telegram, 21 September 2015, retrieved 25 September 2015
  34. ^ Lobao, Martim (22 September 2015). "Telegram v3.2 Brings Channels For Broadcasting Your Messages To The World". Android Police.
  35. ^ Telegram Stickers, Telegram, 2 January 2015, retrieved 5 January 2016
  36. ^ a b "FAQ for the Technically Inclined". Telegram. Retrieved 9 January 2016.
  37. ^ Description of MTProto Mobile Protocol, Telegram
  38. ^ "Telegram FAQ". n.d. Retrieved 10 February 2014.
  39. ^ Franceschi-Bicchierai, Lorenzo (24 February 2015). "Encryption Fails: When to Freak Out and When to Chill". VICE Motherboard. Retrieved 9 January 2016.
  40. ^ Perfect Forward Secrecy, Telegram, 14 December 2014
  41. ^ "Hacker News: Telegram – secure, free messaging". Retrieved 11 December 2015.
  42. ^ a b c Jakobsen, Jakob; Orlandi, Claudio (8 December 2015). "On the CCA (in)security of MTProto" (PDF). Cryptology ePrint Archive. International Association for Cryptologic Research. Retrieved 11 December 2015.
  43. ^ Cox, Joseph (10 December 2015). "Why You Don't Roll Your Own Crypto". Motherboard. Vice Media LLC. Retrieved 11 December 2015.
  44. ^ Turton, William (19 November 2015). "Cryptography expert casts doubt on encryption in ISIS' favorite messaging app". The Daily Dot. Retrieved 11 December 2015.
  45. ^ "Telegram, el chat que compite con Whatsapp". El País (in Spanish). UY. Retrieved 8 January 2016. {{cite web}}: Unknown parameter |trans_title= ignored (|trans-title= suggested) (help)
  46. ^ Rull, Antonio (2 February 2014). "Pavel Durov, creador de Telegram: "Ninguna aplicación es 100% segura"" [Pavel Durov, creator of Telegram: "No application is 100% safe"]. eldiario.es (in Spanish). Retrieved 12 February 2014.
  47. ^ overtake (1 December 2015). "overtake/telegram". GitHub. Retrieved 8 January 2016.
  48. ^ telegramdesktop. "telegramdesktop/tdesktop". GitHub. Retrieved 8 January 2016.
  49. ^ Aseman Land. "Aseman-Land/Cutegram". GitHub. Retrieved 8 January 2016.
  50. ^ Aseman Land. "Cutegram". Aseman. Retrieved 8 January 2016.
  51. ^ a b c d e "Telegram Apps". Telegram.org. Retrieved 9 January 2016.
  52. ^ vysheng. "vysheng/tg". GitHub. Retrieved 9 January 2016.
  53. ^ peter-iakovlev (18 November 2015). "peter-iakovlev/Telegram". GitHub. Retrieved 8 January 2016.
  54. ^ "Telegram se actualiza para la pantalla del iPad" (in Spanish). Cnet. {{cite web}}: Unknown parameter |trans_title= ignored (|trans-title= suggested) (help)
  55. ^ DrKLO. "DrKLO/Telegram". GitHub. Retrieved 8 January 2016.
  56. ^ "Telegram-Anleitung: So benutzt man den Messenger" (in German). Newsslash.
  57. ^ "Telegram se actualiza con compatibilidad para Android Wear" (in Spanish). Sevilla: ABC. Retrieved 7 December 2014. {{cite web}}: Unknown parameter |trans_title= ignored (|trans-title= suggested) (help)
  58. ^ a b c Igor Zhukov. "zhukov/webogram". GitHub. Retrieved 8 January 2016.
  59. ^ "Telegram app". Launchpad.
  60. ^ "Telegram app". OpenRepos.
  61. ^ Roble, Patricio (3 March 2014). "Can Telegram Beat WhatsApp with a Public API?". ProgrammableWeb.
  62. ^ King, Bertel (27 February 2015). "WhatsApp+ Developer Releases Telegram+ After Being Forced To Drop The First Project". AndroidPolice.
  63. ^ "WhatsApp+ Is Now Officially Dead After Receiving A Cease And Desist From The Real WhatsApp". Android Police. 21 January 2015.
  64. ^ "Socializer Messenger App Offers a New Approach to Messaging". 14 September 2015.
  65. ^ Carter, Eric (27 June 2015). "Telegram Launches Bot API and Platform". ProgrammableWeb.
  66. ^ Butcher, Mike (24 June 2015). "Telegram's New Platform Lets Developers Create Smart Message Bots With Multiple Uses". TechCrunch.
  67. ^ Ubpin, Bruce (23 February 2016). "Introducing The Forbes Newsbot on Telegram". Forbes.
  68. ^ Bernard, Travis (15 March 2016). "Check out the new AI-powered TechCrunch news bot on Telegram messenger". TechCrunch.
  69. ^ "WhatsApp und Alternativen: Datenschutz im Test" [WhatsApp and alternatives: data protection tested]. Stiftung Warentest (in German). 26 February 2014. Retrieved 2 March 2016.
  70. ^ "Secure Messaging Scorecard". Electronic Frontier Foundation. 27 February 2015. Retrieved 7 December 2015.
  71. ^ Howell O'Neill, Patrick (5 November 2014). "The fight over EFF's Secure Messaging Scorecard". The Daily Dot. Retrieved 7 December 2015.
  72. ^ "Winter Contest Ends". Telegram. 2 March 2014. Retrieved 24 October 2015.
  73. ^ "Crypto Contest Ends". Telegram. 11 February 2015. Retrieved 24 October 2015.
  74. ^ Marlinspike, Moxie (19 December 2013). "A Crypto Challenge for the Telegram Developers". Thought Crime. Retrieved 2 March 2014.
  75. ^ Wauters, Robin (19 December 2013). "Cracking contest: first one who breaks Telegram gets $200,000 in bitcoins (but really, nobody wins)". Tech.eu. Retrieved 2 March 2014.
  76. ^ Hornby, Taylor (19 December 2013). "Telegram's Cryptanalysis Contest". Crypto Fails. Retrieved 24 October 2015.
  77. ^ "تلگرام فیلتر نشده است" (in Persian). Tehran: Tasnim News Agency. 11 May 2015. Retrieved 29 October 2015. Though it is claimed by many that the Telegram is banned, but it is operating normally in Iran.
  78. ^ a b Alimardani, Mahsa (28 August 2015). "Is Telegram's Compliance with Iran Compromising the Digital Security of Its Users?". Global Voices Online. Retrieved 30 August 2015.
  79. ^ "Telegram FAQ". Telegram. Retrieved 14 September 2015.
  80. ^ Lomas, Natasha. "Telegram Now Seeing 12BN Daily Messages, Up From 1BN In February". TechCrunch. Retrieved 19 November 2015.
  81. ^ Zavolokyn, Gennady. "Павел Дуров прокомментировал для CNN историю с подготовкой теракта через Telegram". TJournal.ru (in Russian). Retrieved 20 October 2015.
  82. ^ Steve Ragan (16 November 2015). "After Paris, ISIS moves propaganda machine to Darknet". CSO Online.
  83. ^ "Isis Telegram channel doubles followers to 9,000 in less than 1 week". Yahoo News. 12 October 2015.
  84. ^ "Encrypted messaging app Telegram shuts down Islamic State propaganda channels". Telegraph.co.uk. Retrieved 19 November 2015.
  85. ^ "One app maker has shut down almost 80 secret channels used by ISIS to communicate". Business Insider. Retrieved 19 November 2015.
  86. ^ "Secretive messaging app used by IS takes down posts". CNBC. Retrieved 19 November 2015.
  87. ^ Sanger, David; Perlroth, Nicole (16 November 2015). "Encrypted Messaging Apps Face New Scrutiny Over Possible Role in Paris Attacks". The New York Times. Retrieved 19 November 2015.
  88. ^ Foges, Clare. "Why is Silicon Valley helping the tech-savvy jihadists?". The Telegraph. Retrieved 9 December 2015.
Wikimedia Commons has media related to Telegram Messenger.
Retrieved from "https://en.wikipedia.org/w/index.php?title=Telegram_(software)&oldid=710550230"