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6 changes: 3 additions & 3 deletions encryption_works.md
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Expand Up @@ -83,7 +83,7 @@ Stories about the [lengths](http://www.nytimes.com/2013/08/18/magazine/laura-poi

There are dozens of reasons people should use encryption even if you're not a journalist or a whistleblower—your medical details, credit card info, and personal photos shouldn't be fair game for hackers or governments.

The NSA isn't the only adversary journalists have to be wary of. Imagine a newsroom that relies on a cloud-based storage system for documents. You and your colleagues are working on a story over the course of a few weeks. Just as you're beginning to edit the final draft, a reporter is fired. He returns his work laptop but nobody thinks to revoke his access to the cloud storage system your newsroom uses. He takes the story and the months of research to a rival newspaper and scoops you.
The NSA isn't the only adversary journalists have to be wary of. Imagine a newsroom that relies on a cloud-based storage system for documents. You and your colleagues are working on a story over the course of a few weeks. Just as you're beginning to edit the final draft, a reporter is fired. They return their work laptop but nobody thinks to revoke their access to the cloud storage system your newsroom uses. They take the story and the months of research to a rival newspaper and scoop you.

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They take the story and the months of research to a rival newspaper and scoop you.

What steps could have been taken to stop this from happening? Working through this scenario will go a long way towards threat modeling, meaning we figure out the threats facing us and decide how best to defend against them.
It starts by asking questions such as:
Expand Down Expand Up @@ -327,7 +327,7 @@ In the screenshot above, you can see the OTR fingerprints for both users in the

OTR fingerprints are 40 characters. It's statistically impossible to generate two OTR keys that have the same fingerprint. However, it is possible to generate an OTR key that isn't a collision but looks like one on cursory inspection. For example, the first few characters and last few characters could be the same with different characters in the middle. For this reason, it's important to compare all 40 characters to be sure you have the correct OTR key.

Without verifying keys you have no way to know that you're not falling victim to an undetected, successful MITM attack. Even if the person you're talking to is definitely your real friend because she know things that only she would know, and you're using OTR encryption, an attacker might still be reading your conversation. This is because you might actually be having an encrypted OTR conversation with the attacker, who is then having a separate encrypted OTR conversation with your real friend and just forwarding messages back and forth. Rather than your friend's fingerprint your client would be seeing the attacker's fingerprint. All you, as a user, can see is that the conversation is "Unverified".
Without verifying keys you have no way to know that you're not falling victim to an undetected, successful MITM attack. Even if the person you're talking to is definitely your real friend because they know things that only they would know, and you're using OTR encryption, an attacker might still be reading your conversation. This is because you might actually be having an encrypted OTR conversation with the attacker, who is then having a separate encrypted OTR conversation with your real friend and just forwarding messages back and forth. Rather than your friend's fingerprint your client would be seeing the attacker's fingerprint. All you, as a user, can see is that the conversation is "Unverified".

That said, it's better to use OTR unverified than it is to have a sensitive conversation through an unencrypted channel. Although manual fingerprint verification is the most secure way of verifying a chat partner's identity, there are some on-the-fly methods, such as when Laura Poitras asked someone both she and Snowden were in contact with to tweet Poitras's fingerprint, which provided external verification of the key:

Expand Down Expand Up @@ -605,7 +605,7 @@ The Tails [installation guide](https://tails.boum.org/doc/first_steps/persistenc
When it comes to privacy and anonymity, Tails is currently one of the best operating systems out there, so it's a good tool to have in your journalistic arsenal. The benefits of using it compound if your colleagues are using it too. Here's how to get several people up and running on Tails.

1. Download and burn a Tails DVD. Boot to Tails and create Tails USB sticks for each person.
2. When everyone has a Tails USB stick, each person should boot to Tails on her own laptop and configure a persistence volume on her USB stick. Since this volume is encrypted, each person should come up with her own secure passphrase that she will need to enter each time she boots to Tails. Everyone should reboot their laptops into Tails again and this time mount the persistent volume.
2. When everyone has a Tails USB stick, each person should boot to Tails on their own laptop and configure a persistence volume on their USB stick. Since this volume is encrypted, each person should come up with their own secure passphrase that they will need to enter each time they boot to Tails. Everyone should reboot their laptops into Tails again and this time mount the persistent volume.
3. Each person should create a new pseudonymous Jabber account. (Refer back to [The Intercept](https://firstlook.org/theintercept/2015/07/14/communicating-secret-watched/) for a how-to.) Since Tails makes all Internet traffic go over Tor, this is effectively making an anonymous Jabber account.
4. Each person should open Pidgin and configure it to use their new Jabber account and create a new OTR key. Everyone should add one another to their buddy lists and start OTR sessions with each other. Since everyone is in the same room, this is the perfect time to compare fingerprints and verify the identity of all parties so that you'll able to communicate securely over the Internet in the future.
5. Each person should create a new pseudonymous email address as well. Some email providers, such as Gmail, make it very difficult to create new accounts while using Tor and staying anonymous, so find another email provider to use instead. Make sure the email provider supports IMAP (so you can use a desktop email client) over SSL/TLS (so your email client uses encryption when communicating with the email server). If everyone chooses the same email provider, sending emails between accounts should never leave that email server, which reduces the metadata about your email usage available to anyone conducting dragnet surveillance of the Internet.
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