1. Introduction

EphPub (Ephemeral Publishing) implements a novel key storage mechanism for time-bounded content, that relies on the caching mechanism of the Domain Name System (DNS). Please refer to the following sections to learn how to install and use the application.

2. Install EphPub Addon

The EphPub can be installed on both Mozilla Firefox and Thunderbird. The extension requires Python library to function properly.

Here are the steps to install the extension:

1. Download PythonExt, regarding your OS configuration, from the "Download" page. Note that the current versions of extension provided here only work on Firefox 3.6.* and Thunderbird 3.1.*.
2. Install the Python Extension on Firefox or Thunderbird
3. Download "ephpub-firefox-1.0.xpi" (for Firefox) or "ephpub-thunderbird-1.0.xpi" (for Thunderbird) from the "Download" page.
4. Install the extension on the desired application.

2.1 Requirements

• Firefox 3.6.*
• Thunderbird 3.1.*
• Python Extension for Mozilla 1.9.2

3. Install EphPub Command-line Tool

The EphPub is also provided as a desktop application to create time-bounded files. The software is platform-independent.

You can download "EphPub-CMDTool-1.0.zip" from the "Download" page, unarchived it and start using it. Please refer to following sections to learn about using the software in more details.

4. Use EphPub Addon

Followings are the steps to create and read EphPub messages using the Firefox or Thunderbird extension:

• Create EphPub Messages:
1. Select a text, which you want to encrypt, from a preferred web-mail (e.g. gmail, hotmail, yahoo, etc.) or a text area (e.g. Facebook messaging) or an input field

2. Right click or select the tools menu, and choose EphPub->Create EphPub Message

3. The EphPub email content will be generated with the encrypted version of the message, plus auxiliary information to store the encryption keys on the DNS cache servers. The content will substitute the message selected, if the element in which the text is located in editable. Otherwise a dialog box will pop up and show the content which the user should manually copy and paste.

• Reading EphPub Messages:
1. Select the EphPub content

2. Right click or select the tools menu and choose EphPub->Read EphPub Message.

3. Decryption key will be recovered as long as the expiration time is not yet passed. In such case, the original message can be decrypted and displayed.

5. Use EphPub Command-line Tool

Followings are the steps to encrypt and decrypt files using the command-line tool:

1. Edit config file to modify your preferences. See below for config file details (Optional).
2. run ./encrypt {FILE} {OUTPUT}: to encrypt the content of a file ({FILE}). It generates an output file ({OUTPUT}) containing the ciphertext, and the auxiliar information (i.e. the VDO).
3. run ./decrypt {VDO_FILE} {DECRYPTED}: to decrypt an EphPub-based encrypted file ({VDO_FILE}). The cleartext is stored in a file ({DECRYPTED}).
4. You can generate random domains using ./generate_randDoms.

5.1 Requirements

• Python 2.5 or higher

6. Caveat

The EphPub extension is a prototype implementation. Please use at your own risk.

The project is still in the Test phase and currently we can guarantee that the extension works on Firefox 3.6.16 and 3.6.17 on UBUNTU 10.4, Firefox 3.6.16 and 3.6.17 on MacOS X and Firefox 3.6.17 on Windows 7.

The extension is tested on:

• Gmail: sending encrypted emails and decrypting received encrypted messages.
• Facebook:
1. Sending encrypted messages and decrypting received ones.
2. Posting encrypted messeage on user's wall and decrypt the posts.
3. Sending encrypted notes and decrypting received ones.
• Yahoo! Mail: sending encrypted emails and decrypting received encrypted messages.

The above list will be updated soon.Please feel free to report any successful or unsuccessful configurations to mailto:ephpub@gmail.com or post them on Issues tab http://code.google.com/p/ephpub/issues/list.