#voip

An Introduction to the SIP Diversion Header
▻https://andrewjprokop.wordpress.com/2014/09/22/an-introduction-to-the-sip-diversion-header

The SIP Diversion Header

RFC 5806 defines SIP diversion as follows:

A change to the ultimate destination endpoint of a request. A change in the Request-URI of a request that was not caused by a routing decision. This is also sometimes called a deflection or redirection.
A diversion can occur when the “user” portion of the Request-URI is changed for a reason other than expansion or translation.
A diversion can occur when only the “host” portion of the Request-URI has changed if the change was due to a non-routing decision.

This usually boils down to the scenario where A calls B and A is redirected (not transferred) to C.

Imagine Sarah setting call forward on her SIP telephone to send all incoming calls to Debbie. Now, when Andrew calls Sarah, his call will be automatically sent to Debbie. Debbie’s SIP telephone will know that the call was diverted by the presence of a Diversion header in the INVITE request she receives from Andrew.

Who inserted the Diversion header? It won’t be Andrew since he is unaware of the state of Sarah’s telephone. It won’t be Sarah since her telephone never saw Andrew’s call. It certainly can’t be Debbie since it’s her telephone that is ringing. This means that it must be something between Andrew and Debbie.

That something will be some form of a Back-to-Back User Agent (B2BUA) and in most cases it will be a SIP proxy that is aware of the forward conditions of the endpoints it serves. The Diversion header will be added by the proxy when it sees Andrew’s INVITE to Sarah. That altered INVITE will then be proxied to Debbie.

You can read all about B2BUAs in my article, The Back to Back User Agent (B2BUA).

In my example, I stated that Sarah’s telephone was forwarded to Debbie. Of course, there are a number of different call forward conditions. In the SIP world, these are designated as diversion-reasons with the following permissible values:

unknown
user-busy
no-answer
unavailable
unconditional
time-of-day
do-not-disturb
deflection
follow-me
out-of-service
away

Additionally, a Diversion header supports three other parameters:

counter: This contains the total number of diversions that have occurred.
screened: This indicates if the diversion number is user provided (“no”) or network provided (“yes”).
privacy: Certain conditions require that the diversion information be encrypted. This parameter shows how privacy has been applied.

The following is an example of a fully populated Diversion header:

Diversion: <sip:2000@192.168.254.254>;privacy=off;reason=no-answer;counter=1;screen=no

Anyone receiving an INVITE with this header knows that 2000 was the originally called number, no privacy was applied, the call was forwarded due to a no answer condition, this is the only diversion, and the diversion number was user provided.

A single INVITE may contain multiple Diversion headers. Those headers are ordered such that the last or most recent diversion is at the top of the list and all subsequent diversions are below it.
Making SIP Trunks Happy

In the past, I have encountered situations that required a Diversion header that had nothing to do with call forwarding. The most common is when you need to call out through a carrier SIP trunk and the From header in the INVITE contains a number not provisioned by the carrier. The carrier would look at the From value, not recognize it, and subsequently reject the call. In some cases, a Diversion header can be used to provide the carrier with a number that it does recognize.

The reasons why the carrier might reject the call are varied, but the most common one I’ve encountered is that carriers need to see a number in its pool of DIDs to properly handle 9-1-1 calls. The value in the Diversion header can be used to satisfy that requirement.
Mischief Managed

This article was meant to be an introduction to the Diversion header and I hope that I accomplished that. You are more than welcome to dig through the SIP RFCs for a deeper explanation, but for most of you that won’t be necessary.

Happy diverting!

#VoIP #SIP #téléphone

Foreign workers in the Gulf still can’t call home
▻https://www.codastory.com/authoritarian-tech/gulf-foreign-workers

Our story featured a Filipino administrator in a labor camp near Doha and found that because most free Voice over Internet Protocol (VoIP) apps such as WhatsApp and Skype, Facetime were blocked by authorities in Gulf countries like Qatar, Oman and United Arab Emirates, migrants were hardly able to communicate with their friends and relatives back home. Human rights organizations have called for Gulf countries to lift the ban on free VoIP services. The UAE, Qatar and Oman have eased some (...)

#FaceTime #Skype #WhatsApp #VoIP #migration #censure #surveillance

https://www.codastory.com/wp-content/uploads/2020/07/1-1.jpg

Rage Against the Sectarian Machine

On Thursday 17 October, the Lebanese government proposed a new tax of 0.20 USD per day (£4.60 a month) on Voice Over Internet Protocol (#VOIP) calls, affecting mostly WhatsApp calls. In a country paying highly for a chronically inadequate and under-invested telecommunication infrastructure, this was not a good move. According to a McKinsey report in January 2019, Lebanon has the 130th slowest internet out of 133 countries. In other words, Lebanon – a country where, officially, war finished in 1990 – has slower internet than a war zone. Moreover, according to the same report, mobile data and voice prices are two or three times higher than regional peers, making it one of the least affordable in the region.

The “Whatsapp tax”, however, is only a detail in a much wider Lebanese landscape, where public infrastructure and the natural resources that partly sustain it are crumbling under inadequate or absent policies, corruption, and environmental and real estate abuse within a voracious neoliberal market logic. Examples of this process include the privatisation of much of the country’s coastline, the illegal quarrying of mountains to nurture the real estate boom, especially after the end of the 1975-1990 civil war (resulting in higher risk of mudslides and flash floods), patchy planning and zoning practices (Bou Akar 2018) , mismanagement of waste services that grew into a nationwide crisis in 2015 and, finally, wild fires that, in the three days preceding the ‘#Whatsapp_Tax’ idea, wiped out 1,200 hectares (2,965 acres) of forest, according to expert George Mitri. The fires spread amidst state inertia: three crowdfunded firefighting helicopters sat idle and in disrepair, with the lack of fire rangers due to the stall in appointments the previous year.

▻https://urbanviolence.org/rage-against-the-sectarian-machine
#Liban #taxe

GCHQ already had developed an “insecure by design” end-to-end phone encryption protocol (as opposed to link encryption) that contains a backdoor: MIKEY-SAKKE, as discovered by University College London researcher Steven J. Murdoch

He describes this in a quite interesting (and lengthy) article on his appropriately called blog:
▻https://www.benthamsgaze.org/2016/01/19/insecure-by-design-protocols-for-encrypted-phone-calls

access to private keys would be provided by companies operating communication networks, and so may be more vulnerable to hacking, intimidation of employees or insider abuse, as well as allowing less oversight.

[...]

The design of MIKEY-SAKKE is motivated by the desire to allow undetectable and unauditable mass surveillance, which may be a requirement in exceptional scenarios such as within government departments processing classified information.

[...]

MIKEY-SAKKE is the latest example to raise questions over the policy of many governments, including the UK, to put intelligence agencies in charge of protecting companies and individuals from spying, given the conflict of interest it creates.

RFC 6509 : MIKEY-SAKKE: Sakai-Kasahara Key Encryption in Multimedia Internet KEYing (MIKEY)
▻https://tools.ietf.org/html/rfc6509

This document describes the Multimedia Internet KEYing-Sakai-Kasahara Key Encryption (MIKEY-SAKKE), a method of key exchange that uses Identity-based Public Key Cryptography (IDPKC) to establish a shared secret value and certificateless signatures to provide source authentication. MIKEY-SAKKE has a number of desirable features, including simplex transmission, scalability, low-latency call setup, and support for secure deferred delivery.

#encryption
#privacy #surveillance
#backdoor #key-escrow
#Clipper
#ZTRP #SCIP
#VoIP

Tutoriel pour construire une cabine téléphonique de rue gratuite

▻http://www.taringa.net/posts/hazlo-tu-mismo/4333668/Hacer-una-cabina-telefonica-gratuita-en-la-calle.html

Dîtes, les pros, ça vous semble à jour comme process et configuration ?

Parce que ça donne des idées pour certains lieux amis ;-)

http://www.obsoletos.org/wp-content/uploads/2009/04/telefono_hamlab_patio.jpg

¿Que es Asterisk?

Asterisk es una aplicación de software libre (bajo licencia GPL) que proporciona funcionalidades de una central telefónica (PBX). Como cualquier PBX, se puede conectar un número determinado de teléfonos para hacer llamadas entre sí e incluso conectar a un proveedor de VoIP o bien a una RDSI tanto básicos como primarios. Fuente: Wikipedia

¿Como se instala?

Lo instalaremos en Debian, una distribucion GNU/Linux. Para empezar actualizaremos los repositorios al listado mas reciente de paquetes e instalaremos las actualizaciones pendientes.

# apt-get update

# apt-get dist-upgrade

[...]

Un décret autorise les captations de données et de conversations Skype en temps réel
▻http://www.nextinpact.com/news/97804-un-decret-autorise-captations-donnees-et-conversations-skype-en-te

Dans le calme d’un dimanche précédent le début des vacances de Noël, le gouvernement a publié au Journal officiel un décret autorisant les forces de l’ordre à surveiller toutes les informations apparaissant sur l’ordinateur d’un suspect (de ses conversations Skype à ses sites consultés), dans le cadre de procédures judiciaires. Permettre à des enquêteurs de capter en temps réel (et à distance) les données informatiques de suspects, c’est possible. Depuis le vote de la LOPPSI de 2011, l’article 706-102-1 du (...) #Skype #écoutes_téléphoniques #CNIL #surveillance #LOPPSI

How To: Setup a Private #VOIP Phone System for Android | The Guardian Project
▻https://guardianproject.info/2010/05/26/how-to-setup-a-private-mobile-phone-system-for-android-and-beyond

When we take into account network performance and audio fidelity requirements, as well as the International nature of Guardian’s target users (everything from average citizens to multi-national journalists or humanitarian organizations), the prospect of a truly real-time secure VOIP solution starts to reveal itself as quite the challenge. Fortunately, a number of efforts have been underway for some time on the Android platform. The following is an introduction to one such effort, and this post provides a very easy step-by-step how to enable your very own private mobile phone system.
...
If you have a relatively small group of colleagues (NGO, humanitarian workers, activists, journalists, etc.), it allows you to easily establish a private internal phone system that can be used over a data connection in lieu of the regular phone system. In our experience, the call quality is also quite good. And while the following step-by-step guide will lead you through the process of setting up this simple solution, first a word of caution: this is not a secure solution yet. It is a first step, however, down that road. To achieve a more secure solution, we need to enable more features, include tunneling and encrypting traffic through a Virtual Private Network (VPN) as well as integrating to a privately maintained Asterisk phone server running with custom security settings.

#firefox 34, ce Hérault - LinuxFr.org
▻http://linuxfr.org/news/firefox-34-ce-herault#firefox-hello

Firefox #hello est une application de communication en temps-réel (ou synchrone) offrant du #chat et de la voix, tout ceci étant basé sur WebRTC. Hello est encore expérimental à ce jour.

#voip #visioconférence

Tox : la messagerie sécurisée pour tous
►https://tox.im

Un protocole de #messagerie_instantanée (avec audio et vidéo possible) crypté. Voir ▻http://tox.dhs.org pour le plugin permettant de l’intégrer dans #pidgin

#voip #opensource #sécurité #vie_privée #chat #skype #IM

NXTTY - Crypto messaging for the masses !
▻http://nxtty.com

Nxtty is a crypto messenger which allows you to send encrypted messages to one or more users at a time.

[…]

Nxtty is built on the Nxt decentralized peer to peer cryptographic platform. Once a Nxtty user has added you to their contact list an unbreakable link is established between you. This link is almost like a physical phone line that NO ONE can cut or wiretap. Thru this secure crypto link you can send each other message & images which no other person, organization or government can intercept.

Ça vient de sortir (avec pas mal de comm et sans white paper (ou en tout cas j’ai pas trouvé)).

Le dépot Git : ▻https://bitbucket.org/JeanLucPicard/nxt/src
L’appli’ Android : ▻https://play.google.com/store/apps/details?id=com.nxtty.main

Qu’en pensez-vous ?

#Application_mobile #Blockchain #Chiffrement #Messagerie_instantanée #NXT #NXTTY #P2P #Pair_à_pair #VoIP

BitTorrent Bleep Alpha Goes Public, Introduces Mac and Android apps
▻http://blog.bittorrent.com/2014/09/17/bittorrent-bleep-alpha-goes-public-introduces-mac-and-android-apps

Private Voice Private Voice & Text App Opens Test Community to All Interested Parties

Communicating with friends, family and coworkers is easier than ever, but at what cost? The Internet promotes the free exchange of information, but we often sacrifice privacy for the sake of convenience. Cloud-based services store personal information and private moments on servers, making them vulnerable to attacks.

Here at BitTorrent, we’re working on a way to change that.

Bleep (aka BitTorrent Chat) est disponible en alpha pour tous (Windows, Mac OS et Android). BitTorrent est une technologie qui a fait ses preuves, donc c’est à tester, même si c’est quand même très problématique que ce soit pas open source...
De mon côté je cherche l’APK...

#BitTorrent_(protocole) #Bleep #Communication #Messagerie_instantanée #Open_source #Pair_à_pair #Peer-to-peer #Version_alpha #VoIP #Voix_sur_IP

On the state of Free #VoIP:
▻http://www.earth.li/~noodles/blog/2014/07/on-the-state-of-free-voip.html

« #viber a été bloqué au #liban, en raison de son origine, (une compagnie israélienne basée à #chypre). »
▻http://levant.tumblr.com/post/62429878226

“Viber a été bloqué au Liban, en raison de son origine, (une compagnie israélienne basée à...

#iphone #android #smartphones #app #communication #voip #telecommunications #gsm #portable #mobile #cell #cellulaire #israel #economie #politique

You were using #Skype instead of #SIP because you found it easier ? Meet the Skype killer - now quick and easy to integrate in any #Web environment. ▻http://danielpocock.com/get-webrtc-going-fast #telephony #RTC #WebRTC #VOIP