BitTorrent develops secure, decentralized chat program using public-key crypto

The program will use the BitTorrent DHT peer finding protocol to locate contacts without a central server

BitTorrent Chat encrypts communications directly between users

BitTorrent Chat encrypts communications directly between users

BitTorrent, the company behind the popular file sharing protocol with the same name, is developing a secure chat application that will encrypt all communications between users and won't use any central server to route messages.

The company announced that it planned to develop the secure messaging product, called BitTorrent Chat, in September. However, at that time there were no technical details available about it's possible implementation.

The product is still far from a stable release, but the BitTorrent developers have made progress since the original announcement and revealed more about the program's architecture in a series of blog posts Thursday.

The most fundamental difference compared to many existing chat programs is that BitTorrent Chat won't rely on a central server to deliver messages from the sender to their recipients. The encryption will be done directly among clients, not between the clients and a server.

Chat applications that rely on centralized, cloud-based servers are vulnerable to hackers or "NSA's dragnet surveillance sweeps," Christian Averill, BitTorrent's director of communications said in a blog post. "While we're hearing legislative calls to curb domestic spying, and corporate assurances regarding user privacy, we can't rely on these systems. Statements like 'just because we can, doesn't mean we should' don't guarantee user privacy."

In the absence of a central server to route messages between users, BitTorrent Chat users will find each other through the same mechanism that many BitTorrent clients use to locate file-sharing peers -- a Distributed Hash Table (DHT).

"In essence, the DHT is a web of peers cooperating," Abraham Goldoor, a software engineer on the BitTorrent Chat team explained in a separate blog post. "You ask your closest neighbor if they know of the person you are looking for. You then ask their neighbors, and their neighbors' neighbors, and so on. Eventually, you'll get to a peer (neighbor) who knows the address of the person you're looking for. They return this address to you. This is done in such a way that only you know who you are looking for."

In order to accommodate BitTorrent Chat's requirements, the DHT protocol itself has been updated to support encryption.

With BitTorrent Chat users will be identified by their public keys, which is part of a public-private key pair used for encrypted communications. Two users only need to exchange their public keys with each other to be able to chat securely.

Since there will be no traditional usernames and users will be identified by their keys, the infrastructure will also provide some level of anonymity.

However, even when used directly between users and not between users and a central server, public-key-based encryption does not protect against all types of attacks. For example, in most common implementations, if a private key is stolen, it can be used to decrypt all past and future messages encrypted with its corresponding public key.

To counter that, the BitTorrent Chat developers will implement a cryptographic feature known as forward secrecy. "Every time you begin a conversation with one of your contacts, a temporary encryption key will be generated," Goldoor said. "Using each of your keypairs, this key will be generated for this one conversation and that conversation only, and then deleted forever."

BitTorrent Chat is still in alpha stages of development, but users can apply to become early testers.

Tags bittorrentinstant messagingInternet-based applications and servicesonline safetysecurityencryptionprivacy

Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Lucian Constantin

IDG News Service

Comments

Comments are now closed.

Latest News Articles

Most Popular Articles

Follow Us

GGG Evaluation Team

Kathy Cassidy

STYLISTIC Q702

First impression on unpacking the Q702 test unit was the solid feel and clean, minimalist styling.

Anthony Grifoni

STYLISTIC Q572

For work use, Microsoft Word and Excel programs pre-installed on the device are adequate for preparing short documents.

Steph Mundell

LIFEBOOK UH574

The Fujitsu LifeBook UH574 allowed for great mobility without being obnoxiously heavy or clunky. Its twelve hours of battery life did not disappoint.

Andrew Mitsi

STYLISTIC Q702

The screen was particularly good. It is bright and visible from most angles, however heat is an issue, particularly around the Windows button on the front, and on the back where the battery housing is located.

Simon Harriott

STYLISTIC Q702

My first impression after unboxing the Q702 is that it is a nice looking unit. Styling is somewhat minimalist but very effective. The tablet part, once detached, has a nice weight, and no buttons or switches are located in awkward or intrusive positions.

Resources

Best Deals on GoodGearGuide

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?