Affordable encrypted VoIP

Demo video


TiviPhone is a market-leading VoIP softphone for various smartphone platforms. It also encrypts voice and video with the scientifically proven, open-source ZRTP.


We are Tivi, the developer and marketer of TiviPhone client software. The company is focusing on competitive and innovative VoIP for international markets.


Tivi solves your telecommunications problems in terms of costs, multimedia, platform interoperability, billing and privacy. Contact us.

Is there wiretapping of VoIP calls?

Yes, if your voice travels over insecure networks such as the internet. You never know how many nodes it is routed through. A global network is also globally vulnerable. Even if you use a regular-looking desk telephone, your telecom provider may in fact route it using a digital IP network where hackers and private investigators might be present. That's why you have to find the most robust, independently reviewed and professional software for the end-points of your call.

Protection against wiretapping?

Install and use our safe and encrypted VoIP software: TiviPhone with ZRTP technology. Encourage your employees and partners to use it too. If you do, you will have protected your identity and privacy with the ZRTP encryption, always strong enough to send your voice and video over the internet safely.

Easy, affordable, compatible

TiviPhone is downloadable instantly. It has four versions: "passive", "economy" and "business", plus a three-day free "business trial". They are meant for free, economy and business users accordingly. Encryption needs ZRTP-enabled clients at both ends of a call (at least the free passive version).

Installing and trying Tivi Phone is easy, and you can purchase the encrypting version at any time via The licensing details are here.

For the user, safeguarding his or her voice/video call requires just one manual step: the checking of short authentication strings (SAS) on the screen of their mobile phone or computer. This verifies that the callers' identities and the encryption negotiation process have not been hijacked or intercepted. All the rest is automated.

Making encrypted voice/video calls

Check indicators - it's encrypted!

TiviPhone with ZRTP encryption is an automated solution that takes care of your crypto key exchange. However, the checking of whether going secure has succeeded is always the users' responsibility, for both the calling user and the callee (see step 5).

Let's see below how a smartphone behaves and what the Tivi softphone indicators are.

Voice-only call Steps Voice-and-video call
"A" - audio      "V" - video
Unencrypted status; checking the partner's ZRTP-compatibility.
1 First, the caller is connected to the called party. While the voice or video connection is active but not yet encrypted, your Tivi Phone program detects if the party you are calling can use the ZRTP protocol. [_going_secure_V.gif]
Note the open red "A" and "V" padlocks!
Negotiating encryption.
2 After ZRTP peer connection, the "going secure" phase takes care of the encryption negotiation. This might take up to 5 seconds, depending on a variety of network conditions. [_going_secure_V2.gif]
The yellow padlocks indicate the negotiating in progress.
[secure_aes256.gif] 3 The display of a closed, green padlock confirms that the encryption has succeeded. [_secure_V.gif]
Note the closed green "A" and "V" padlocks.
This screen shows the two words to be read aloud and compared.
4 An invitation to the users to read to each other and compare the system-generated "short authentication strings". The callers should read these words displayed at the beginning of the call to each other. If the strings do not agree, this means there is a wiretapper on the line. [_compare.gif]
This screen shows the two words to be read aloud and compared.
[error.gif] 5 Warnings if the ZRTP encryption fails. [_nerr_V.gif]
* Phil Zimmerman discusses this in his FAQ.

Wiretapping suspected? Retry.

If Tivi Phone shows that the crypto negotiation has failed, the users may (if they want to) continue the call in the unencrypted mode, while being aware of the consequences. Or, they may try again - with a different and safer telco provider, another hotspot, different hardware, software, time of calling, and so on.

Good security is unobscured

Some other VoIP vendors rely on obscurity, believing that secreted communications protocols would somehow provide the best privacy. Tivi and the Zfone project, on the contrary, strongly believe in openness and verifiability. Read about it in Tivi's press release on ZRTP-encrypted mobile VoIP, see Zfone project's FAQ, browse the ZRTP entry in Wikipedia and enjoy Zfone's author Philip R. Zimmermann's interview with Forbes.

Need yet more facts? Various countries' businesses, politicians and celebrities have suffered embarrassing damages due to their use of plain unencrypted VoIP or leaked and spied upon phonecalls (source: recent years' news reports).

Three licence types of Tivi Phone with ZRTP.

[img:Licence connections]

B - The user has unlimited powers of secure voiping. Suitable for businesspeople, private individuals and heavy-duty technical users who prefer to have complete control instead of loopholes and want to talk securely to all other ZRTP users.

E - These are economy users who can talk to each other as well as to the "business" users in the ZRTP-encrypted mode. Suitable for groups of users some of whom choose not to pay the higher "U" licence fee.

P - For the passive licence users, the only option is to call or be called by a "business" user if the ZRTP encryption is needed.

In other words, passive-to-passive calls and passive-to-economy calls are always unencrypted.

Note 1. In the case of using unencrypted VoIP (voice & video) and instant messaging, Tivi Phone is free to use by all these groups.

Note 2. The availability of encryption depends on the "highest" licence present in the current phonecall. [B[img:-to-]B], [B[img:-to-]P], [P[img:-to-]B], [E[img:-to-]E], [B[img:-to-]E] and [E[img:-to-]B] all get the encryption! The direction of calling is not relevant.

Note 3. Both parties must have ZRTP-compatible softphones. E.g., a "B licence" call to an incompatible terminal cannot be encrypted.