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JackPair protects your privacy by encrypting your voice over phone calls.  It works with any device through standard 3.5 mm audio jack.
JackPair protects your privacy by encrypting your voice over phone calls. It works with any device through standard 3.5 mm audio jack.
303 backers pledged $44,661 to help bring this project to life.

About this project

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pledged of $35,000 goal

A Huge Thank You to All Backers!

This is the first step toward a better world, and we look forward to continuing the dialogs and creating more momentum throughout this project and beyond.  You can find us at our website

For those who missed the campaign and wanna support us & place orders, you can also find the latest info at


What is JackPair?

JackPair is an affordable tool that enables average citizens to protect themselves against wiretapping.  It’s a pair of encryption devices you put in between your phone and headset, which are connected through standard 3.5mm audio jacks. You can secure your phone line by simply pushing the JackPair button, and your voice will be encrypted. There’s no password to remember, no software to install, no service to subscribe to, and it works with any phone through a standard audio jack.

JackPair in the News

From Bruce Schneier:

"JackPair is a clever device encrypts your voice between your headset and the audio jack. The crypto looks competent, and the design looks well-thought-out. I'd use it."

TechCrunch - "The concept is pretty simple: one box plugs into your phone, whether that’s a smartphone, landline telephone or VoIP client on a PC, via the standard 3.5mm headphone jack ..."

Ars Technica - "JackPair is part of a wider movement that has struggled against a darker facet of the Internet—the ease with which it can be monitored."

eWeek - "The hardware approach of cryptography still has a lot of appeal in establishing secure communications."

TechnologyTell - "How it works is simple."

TechFaster - "Whether you’re in any of the professions above or you’re just concerned about your privacy, JackPair is definitely worth considering."


Many viewers have expressed that the current look of JackPair can be improved.  So we have worked with professional design firms and come up with a few new designs proposals here:

You can vote and comment here on Facebook, leave your feedback in the KS comment section, or contact me for your remarks. We'll pick a winning proposal based on your feedback here and use it as the final industrial design for JackPair.

Affordable Tool For Everyone

The existing secure phones on the market today cost anywhere from over six hundred to a few thousand dollars.  It's out of reach for most people, and the worst part is that, you have to give up the phones you're using everyday, and switch to whatever secure phone models dictated by the vendors.  With JackPair, we're enabling every citizen to protect our own privacy by making it under a hundred bucks, and you get to keep using your favorite phones while talking through JackPair's Secure Line.

One-Click Solution

Using JackPair, you can easily protect your privacy by just pushing the JackPair button.  During a phone call, if both sides have JackPair installed, either side can simply push the JackPair button to pair up the two JackPair devices. This triggers JackPair to encrypt your voice conversation using a One-Time-Secret -Key (OTSK) that is created on the fly. The same OTSK is automatically-created and self-destroyed at both ends without leaving the JackPair box.  This means you don’t have to remember any password, and no one can break into your conversation without this One-Time-Secret-Key.

No Trace Left Behind

At any time during your phone call, when you push the JackPair button, a new One-Time-Secret-Key (OTSK) is generated to encrypt your voice conversation.  This OTSK is created locally in each of the JackPair devices at both ends of the phone call without being exposed over the network(*), and it is destroyed immediately after the phone call is finished, without being stored anywhere outside the JackPair device.  The OTSK is short-lived and self-managed;  it never leaves the JackPair box.  So there is no chance for the OTSK to be compromised by anybody, whether intentionally or accidentally.  This simple security design leaves no trace behind; it not only protects your voice, but also saves us, as the device maker, from the trouble of being harassed by the government or exploited by hackers.

Besides key exchange protocols, the encryption algorithm in JackPair is based on Salsa20 stream cipher, which is selected by eSTREAM, the ENCRYPT Stream Cipher Project organized by the European Union, as part of its final software portfolio since 2008.  Stream Cipher like Salsa20 is a natural fit with OTSK, which is used as the seed for PRNG (Pseudo Randon Number Generator) to create key streams with similar property of One-Time Pad.  JackPair uses open source encryption software and will stay open sourced.

(*): The One-Time-Secret-Key in JackPair is generated using Diffie-Hellman-Merkle key exchange protocol, which is a well-known, fundamental protocol in the security industry since 1976; it allows creation of shared secret without exchanging it over the network (see illustration below).

Direct With No Middleman

JackPair is designed with end-to-end security in mind: there’s no relay server or service provider involved in either the voice encryption or the One-Time-Secret-Key (OTSK) creation, and the OTSK is never disclosed anywhere, not even to the other party on the phone call.  In order to make sure both sides use the same OTSK for voice encryption and there’s no middleman bridging the call, the Pairing Code(*) is designed as a simple way for both parties to authenticate each other through their own voices over the same phone phone.  After your JackPair device has paired up with the other party’s (ie, when the LED light turns from red to green), The first thing you should do is to read the Pairing Code on your screen to the other party over the phone, and verify that the Pairing Code is the same on both ends.  The fact that the other party recognizes your voice and acknowledges with the same Pairing Code means these two JackPair devices are directly connecting with each other, with no middleman bridging the call through any other JackPair devices.

(*): Pairing Code is the abbreviated hash digest number of One-Time-Secret-Key (OTSK).

Work With Any Phone

JackPair is a standard audio adapter that can be plugged into any phone with a headset and microphone. At any time during a phone call, both parties can plug in the JackPair device to continue their conversation in secure mode over the same call.  JackPair is connected with phones through its 3.5 mm audio jack, which is the universal standard as the audio interface for all kinds of devices, including all tablets, laptops, personal computers, and most mobile phones & Voice-Over-IP devices.  For plain old telephone sets, JackPair also includes a RJ9-to-3.5mm converter for handset-free operation(*). Unlike other security devices on the market that are hard to use and work only with specific phones or carriers, JackPair is compatible with all of your favorite phones today. With JackPair, you don’t have to make the trade-off between personal security and life style.

(*): optional accessories included in Full Pack only.

In addition to the 3.5mm audio jack, we also have Bluetooth in our pipeline for the second-generation JackPair. This will make it even easier for you to protect your voice while keep using your favorite phones & gadgets, and it will also prevent Bluetooth headsets from being eavesdropped, since your voice is encrypted by JackPair before it’s transmitted through Bluetooth headsets.  Stay tuned for more update on Bluetooth.

Open Source Security

We plan to make it open source for the encryption software in JackPair. This allows our code to be scrutinized by the community and, if there’s any security hole, it’ll be identified & fixed quickly. We understand that security cannot be taken for granted and requires constant vigilance, and open source is a great way for the community to help out and for us to stay alert. 

In addition to open source software, we intend to do open hardware for JackPair as well.  The schematics and gerber-files will be publicly available to make it easier for everyone to review.  The licenses we are considering so far is Creative Commons - Attribution - ShareAlike 3.0.  Let us know if you have better ideas here.

Why JackPair? I Have Nothing to Hide

The right to privacy is not just about “secrecy” or “having something to hide”. With modern surveillance technologies, the Government’s massive data collection and mining programs are problematic even if people have nothing to hide. The large-scale harvest of small bits of seemingly innocuous data allows weaving of a much more telling big picture of individuals, but it often failed to reflect the whole story.   The problem lies in not only information “gathering”, but also information “processing”, and here’s some examples you should worry about:

  • Distortion & Misinterpretation: What if the government mistakenly determines that, based on your pattern of activities, you’re likely to engage in a criminal act? What if the government thinks your financial transactions look odd—even if you've done nothing wrong—and freezes your accounts?
  • Leaking & Secondary Use: What if the government or carrier operator leaks your information to third-parties or the public? What if the government doesn't protect your information with adequate security, and an identity thief obtains it and uses it to defraud you? How long will personal data be stored? And what can it be used for in the future? A lot of times we do not even know about the leakage of our records until long after the damage is done.
  • Exclusion of Access: Most data gathered by the government is kept secret for national security reasons, and people are barred from accessing and correcting errors in that data. What if the government denies you the right to fly without giving you any reason?

An argument could be that the government does not intend to hurt average citizens. In many cases that is true, but the government can, and has, also harmed people inadvertently, due to errors, carelessness, or policy changes. These massive surveillance programs are no longer about what information people want to hide; they make the individuals powerless and vulnerable in front of the bureaucracy, and create a power imbalance between People and Government. To change the dynamics, JackPair is the affordable tool that enables average citizens to protect themselves against wiretapping and harassment from Big Brother. 

The Story Behind JackPair

JackPair is inspired in large part by Edward Snowden. The first Snowden leak led to the revelation that the NSA collects records of every U.S. phone call under a call log metadata program. It shows that the data collection is no longer about targeted acquisition of information to avert threats. Such a massive scale of surveillance programs has undermined the fundamental American values of freedom and privacy. America is sliding into a state of universal surveillance. This also reminds me of the police state where I grew up, Taiwan. Before the democratic reform, the government could spy on you without reasons and arrest you based on words you have said. Even today, there are still WaterGate-like scandals happening and the politicians get away without any accountability.

With all these breaking news unrolled in front of us, I started to ask myself, what can we do to stop the abusive wiretapping and protect the democracy & freedom we all believe in as Americans? If we can’t stop the abuse of power from its root, then what’s the next best thing we can do to protect ordinary citizens from being harassed by the abusive power?

As a network security engineer, I've been involved in both sides of the security arm races; on the defense side, I've built computer firewalls and virtual private networks for millions of uses, and on the offensive side, I’ve designed peer-to-peer protocols and network traversal programs that penetrate those firewalls and VPNs. I know how complex the security technologies can be, and how hard it is for average citizens to make use of the security technologies to defend themselves. Existing solutions available on the market are either too difficult to use, way too expensive, or just not secure at all. So we rolled up our sleeves and built one that’s simple, affordable, and compatible with any phone you already have.

This is how JackPair was born.

The Team At Work

AWIT is consists of a small engineering team with high-caliber professionals in the field of distributed networking, embedded systems, peer-to-peer, mobile game, security, and online/web technologies. From the very beginning of this JackPair project, we had the debate of whether it should be a pure software, mobile app solution, or a standalone hardware product.

Evaluation boards for JackPair prototyping
Evaluation boards for JackPair prototyping

 After surveying the current software solutions on the market, it became clear to us that it’s just too easy to break these mobile apps, and both ends of the conversation must use smart phones for it to work. A hardware product built from scratch is the only way to have the security clearance. The current secure phones on the market costs anywhere from over six hundred to a few thousand dollars, which are out of reach for most people. The challenge is how to build a hardware solution that is affordable, easy-to-use, and compatible with most people’s existing phones at hand.

Initial Design of JackPair
Initial Design of JackPair

With the requirements in mind, we set out to find appropriated evaluation boards for our design. I had started off with TI’s LaunchPad board, then Dark Shenada, AWIT’s guru in embedded system, had taken over and switched to ST Micro’s Discovery Boards. We had some initial success there, but it don't meet our requirements for audio channels, and we think we can do better in terms of reducing the component complexity & cost. With help from our friends of professional consultants for schematics and gerber-file PCB layout, we began to put together our own circuit design with minimal components.

JackPair PCB top/side/bottom views
JackPair PCB top/side/bottom views
After a few crash and burns, with more helps from team members like Scott and Simon, we are able to pack all the functionality required for JackPair into a small PCB the size of a cigarette lighter. At the same time, Jackie, the Jack of All Trade in AWIT team, has spent time with designer and mechanical engineer to come up with industrial design for the housing of JackPair.

What's Next?

With software & hardware prototypes in place, we have started to talk with our friends and partners in the field of contract manufactures, as well as housing and industrial designs.  AWIT has long-term EMS partners locally right here in Silicon Valley, California, so JackPair will be manufactured and assembled in the United States, although some of the parts like accessory cables might be sourced through non-domestic channels.

We're stretching as far as we can into this project, and the next step is to go into mass production. It costs quite a bit for the tooling & material sourcing in volumes, and we definitely need the Kickstarter community’s help now to fund the project and spread the words. So it’s time to debut JackPair here at

After a successful Kickstarter campaign, our next step will be to start the custom tooling & PCB manufacturing process, as well as the testing & certifications required for encryption electronics. Here’s our road map:

  • July/August: meet our sponsors at Kickstarter, finalize industrial design and negotiate manufacturing agreements.
  • September: finalize the mechanical design and place orders for tooling; procurement of electronic parts and materials.
  • October: pilot productions, tooling build-out, quality verification and certificate qualification.
  • November: batch manufacturing of PCB, SMT, and housing.
  • December: assembly and shipment.

How You Can Help

The cost of tooling, electronic materials, PCB layout, testing and certification approval are quite expensive, and more importantly, in order to make JackPair affordable tool for everyone, we need volume manufacturing with economies of scale to bring down the price of each JackPair device.  Many of our friends have jumped in to help with prototyping of JackPair, and your sponsorship is vital for bringing JackPair to the next step of mass production and making it affordable for ordinary citizens to defend their own right to privacy.  So please pledge your support to make JackPair the tool for everyone.

Dragon Innovation has done a 3rd-party review of JackPair and has pre-qualified that we're a team that knows our stuff and that we have a manufacturable product.
Dragon Innovation has done a 3rd-party review of JackPair and has pre-qualified that we're a team that knows our stuff and that we have a manufacturable product.

Risks and challenges

We are a seasoned team with vast experiences in embedded system design and implementation. Although we have existing relationships with the suppliers & manufactures we intend to partner with, they are external to us and may introduce delay during the process. We are confident in our choice of vendors, but also looking for backup suppliers, in case any road block may arise.

The U.S. Government places restrictions on the export of encryption devices like JackPair. Since the encryption software in JackPair is open sourced, we think JackPair is qualified as a self-classified encryption item and can be exported without complex encryption registrations. However, the U.S. exports controls are complex and we are not lawyers. There might be the risk of US government limiting our ability to make JackPair available to citizens worldwide, or even being used within the U.S. In that case, the only alternative would be to have non-U.S. citizens develop the JackPair encryption software from scratch again. This has been referred as the U..S. “export jobs, not crypto” policy.

Shipping JackPair to International users pose another challenge; some countries have made private communications illegal, and there might be risks of confiscation for JackPair shipment. We don’t know the government’s reaction to JackPair yet, and will keep an eye on it. The community can help us in figuring this out collectively, and being creative for workarounds.

Learn about accountability on Kickstarter


  • Software apps can be deployed only for smart phone or PC; it won’t work if the other party you’re calling does not use smart phone or PC. Also, the installation and configuration of software can be a daunting task for the general public.

    As a standalone hardware device, JackPair solves the above problems throught its 3.5mm analog audio jacks, which is the industry standard interface for almost all mobile phones on the market today. And for those older phones & PC without 3.5mm audio jack, JackPair provides adapter cables that anyone knows how to plug in. Compared with software solution, there's no app to install, no password to remember, and you can take JackPair anywhere with you.

    The other important reason is that, it's very difficult for software solutions to guarantee the security of the smart phone it's running on top of. (Just look at how messy the anti-virus industry is today.) If the smart phone itsef is compromised, then all bets are off and the security practice by software app alone is pointless.

    To make it even worse, running encryption software on top of compromised operating system might give you a false sense of security, which makes you even more vulnerable than no security at all; because if you are aware of security danger, then you'd probably make less privacy disclosure over the phone.

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  • No, both ends of the phone call need to plug in their JackPair devices for the encryption and decryption to work symmetrically. To split the cost among your friends, you can buy our $89 Single Pack, and tell all your friends to do the same. It’s also a good way to help spreading the words out!

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  • No, a single JackPair device can pair up with any other single JackPair device over an established phone call. So everybody needs one and only one JackPair device.

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  • No, JackPair devices are matched up dynamically over established phone calls when one of them have its JackPair button pushed. To make sure you are pairing up with the right calling party (instead of man-in-the-middle), you verify that the same Pairing Code is read from the voice of your calling party over the same phone call.

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  • The Pairing Code in JackPair is designed to detect Man-in-the-Middle attack (see the picture of “Why We Need Pairing Code” for illustration.) Pairing Code is the non-reversible derivative (ie, hash code) of the OTSK (One-Time-Secret-Key), which is created on the fly at both ends with the same value (see the picture of “Why JackPair Is Secure” for illustration). By recognizing the other party’s voice that reads out the same Pairing Code over the phone call, you can be assured that no one in the middle is bridging your call.

    It’s alleged that NSA has the ability to synthesize any given human voice in real time. If this is a concern, you can also verify the Pairing Code through “out-of-band” channels like instant messenger, or add your own integrity check on top of Pairing Code; for example, read the MD5 hash, instead of the Pairing Code itself, to the other party.

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  • The 3-digit ("123") Paring Code you see in this web page is just for illustration purpose. The current OLED used in JackPair can display up to 32 digits, though we think 10-12 digits is probably good enough, and more friendly for human reading.

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  • No. JackPair cannot support 3-way conference calls (yet). We are aiming at easy-to-use and affordability/low-cost at this stage, so the design of JackPair is Keeping-It-Simple-Stupid with point-to-point topology. We'll have more bandwidth to work on 3-way design when JackPair becomes popular through your support!

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  • No, JackPair is not your WW-II analog audio scrambler, which is easy to break and gives you a false sense of security. All human voice traffic between two matching JackPair devices are protected by full digital encryption through keys generated on the fly and thrown away immediately after.

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  • We are using Diffie-Hellman at this point, and working on Elliptic curve Diffie-Hellman. See the picture titled “Why JackPair Is Secure” above for illustration.

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  • Synchronous stream cipher is used, with XOR'ed key-stream resulted from pseudo random number generator using OTSK as seed, and periodic marker flag for re-synchronization.

    With limited bandwidth and latency constraint for JackPair to work over voice channel of mobile phones, we cannot afford standard block ciphers like AES, which requires more computing resource and has larger packet size, in comparison to stream cipher. JackPair's OTSK (One-Time-Secret-Key) design also makes it a natural fit for stream cipher, as the same key is never reused. Specifically, the stream cipher we are using is based on Salsa20, which is now one of the final eSTREAM portfolio, after years of scrutiny from the industry.

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  • JackPair uses audio codec from Codec2, which has reasonable good sound quality at 1.2kbps. We have tested JackPair on top of GSM AMR 4.75 (Adaptive Multi-Rate, 4.75kbps) and HR (Half-Rate, 6.5kbps).

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  • Unlike traditional fax-modem technologies, our modem is designed from scratch to fight off the optimization done by GSM codec, including memory-less codec, voice activity detection (VAD)., automatic gain control (AGC) etc.. Basically we have to use synthesized voice to make mobile phones & media servers believe our signal is human voice, not just modulated waves.

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  • You can listen to my voice before, during, and after the encryption through JackPairs over mobile phone network, here:…

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  • Email with PGP encryption is the only widespread solution for random people to communicate easily before JackPair.

    Before you can call us using JackPair, to contact us in person privately, please send your email to:

    jeffrey.chang {at} awitsystems {dot} com

    And here's my PGP public key:

    Key fingerprint = 8D82 2235 C699 21AF 53FE 7ECB 47E1 43C1 DB62 C999



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  • As engineers, we are eliminating our legal obligations, as well as backdoor opportunities, through simplified technical designs that's proven to work, instead of written privacy policy contract that can be voided easily.

    In JackPair, neither the traffic nor the key goes through AWIT, so there's absolutely nothing that AWIT can provide to the security agencies. The key exchange protocol in JackPair is based on the well-known Diffie-Hellman-Merkel algorithm, which allows the creation of shared key without exposing it outside JackPair box (see the animation of "Why JackPair is Secure" in our kickstarter page). And, since JackPair works over established voice phone calls, the voice traffic never go through AWIT, either.

    Also notice that there's no Internet connection on JackPair, wired or wireless, which makes it immune to network-based hacking. Besides audio jacks, the only other interface on JackPair is its USB port, which is used only for battery re-charge in JackPair. The end-to-end encryption does not require any connectivity to third party, including us at AWIT, for JackPair to work, and the encryption cipher algorithm used in JackPair (Salsa20) is also open source and well-examined by tine industry. We're striving to keep ourselves out of the loop by technical design.

    As a US company, we do have to comply with US laws, but the technical design of JackPair makes it free from backdoor or obligation on our part.

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Support this project

  1. Select this reward

    Pledge $1 or more About $1.00 USD

    Love the idea of empowering people to fight against pervasive surveillance? You’re helping to make it happen and get a virtual High 5!

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  2. Select this reward

    Pledge $89 or more About $89 USD

    You will receive 1 set of JackPair + Micro USB cable + 3.5mm TRRP male-to-male audio cable. This is a great deal for you to buy one JackPair for yourself, and tell all your friends to get their owns to engage in private and secure conversations between you and your friends.

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  3. Reward no longer available

    Pledge $139 or more About $139 USD

    The first 100 backer will receive 2 sets of JackPair + Micro USB cables + 3.5mm TRRP male-to-male audio cables. This price is a special deal to thank the first sponsors of JackPair, and it will not be repeated.

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    Reward no longer available 100 backers
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  4. Select this reward

    Pledge $168 or more About $168 USD

    You will receive 2 sets of JackPair + Micro USB cables + 3.5mm TRRP male-to-male audio cables. It’s a great deal for kickstarters that use mobile phones or tablets.

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    64 backers
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  5. Select this reward

    Pledge $198 or more About $198 USD

    You will receive 2 sets of JackPair + Micro USB cables + 3.5mm TRRP male-to-male audio cables + 1-to-2 male-to-female audio cables + 1-to-2 male-to-male audio cables + RJ9-to-3.5mm Headset Adapters. In addition to mobile phones and tablets, these extra adapters allow JackPair to connect with PCs w/ separate earphone and microphones, as well as traditional Plain Old Telephone Sets. It's a great deal for PC or laptop users, or if you have a fixed-line telephone.

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  6. Select this reward

    Pledge $419 or more About $419 USD

    FIVE PACK: You will receive 5 units of JackPair + Micro USB cables + 3.5mm TRRP male-to-male audio cables. This is the mid-level support if Double-Pack is not enough, but Ten-Pack is a bit too much for your need.

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  7. Select this reward

    Pledge $849 or more About $849 USD

    TEN PACK: You will receive 10 sets of JackPair + Micro USB cables + 3.5mm TRRP male-to-male audio cables. This is a great way to help spread the words out among your friends and families by buying JackPairs for them, and support our effort of making JackPair an affordable tools for everyone. For international kickstarter, this volume purchase also reduces the per-unit cost for oversea shipment.

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Funding period

- (37 days)