The Anonymous Network Layer explained

What is the Dusk Network?
The Dusk Network is a decentralized infrastructure focused on providing the sweet-spot between privacy and transparency in payments, communication and asset ownership transfers. It departs from consensus mechanisms like PoW/PoS, which are poorly suited for privacy, to introduce a new privacy-oriented consensus mechanism called Segregated Byzantine Agreement. Dusk is a new blockchain that provides true privacy and a fast and a secure streaming mechanism called Secure Tunnel Switching (STS), all powered by a privacy-oriented cryptocurrency: DUSK.

In this introductory series we aim to take a look at specific aspects of the Dusk Network and explain them in a nutshell. In this article we will look at Dusk’s Anonymous Network Layer, a gossip oriented communication tier inspired by I2P. The Dusk ANL serves to enable full privacy for its decentralized network, and we will explain some of its components in this article.

For a detailed description of The Dusk ANL please refer to the whitepaper.

What is the Dusk Anonymous Network Layer for?
In the vast majority of blockchain implementations, network communication protocols limit themselves to just embracing the privacy standards we have in place today for our daily internet needs: TCP/IP, UDP, SSL for encrypting communication channels to name a few. These protocols are necessary to interconnect network devices on the internet, or as a communications protocol in a private network.

While this can be considered acceptable for centralized environments or platforms where user privacy is not the main proposition, the privacy requirements established with the Dusk network impose the adoption of technology offering a much higher level of privacy protection. To achieve this goal, Dusk is enabling full anonymity over its decentralized network by integrating an advanced, custom bi-directional routing, fully compatible with I2P’s Garlic-Routing technology for all its networking communications, but extending the underlying protocol not only for the deployment of additional functionality (such as fully anonymous file transfer) but also for allowing the default anonymous gossip protocol which powers the entire Dusk network.

The proposed architecture has been designed to make it computationally infeasible for an eavesdropper to tell apart Dusk related traffic from other network activities. Additionally, it should be very hard for any network node to associate a transaction with the IP address of the original initiator.

How does it work?
Dusk’s ANL is inspired by and compatible with I2P’s Garlic Routing technology. Garlic routing generally refers to two things; Layered encryption, and the bundling of messages together. Garlic routing was in turn inspired by ‘Onion Routing’ (TOR). It is relevant to briefly start at the beginning to explain the decision made for the Dusk Network. Onion Routing is a technique that builds paths (tunnels) through a series of peers. Messages are encrypted a number of times, sent through the tunnel, and each peer in the tunnel strips away a layer of encryption and finds just the information it needs to send it onwards. The message and its routing instructions are only fully exposed at the end of the tunnel, once all the (onion) layers have been peeled back. Garlic routing is conceptually similar, but bundles messages together, which makes it more efficient, and makes it more difficult to track a single message if you are insistent on exposing a communication’s intended endpoint.

The Dusk Network uses a more advanced version which roughly works as follows:

  1. Alice and Bob want to transact/communicate.
  2. Alice and Bob are a node or connect to a node.
  3. The node connects to a Voucher Seeder, and obtains a signed list of active nodes.
  4. The node chooses a node from the list to act as an entry tunnel to the Dusk Network, thus bootstrapping Alice’s connection.
  1. Alice’s Entry Tunnel forwards non-repliable packets to the Dusk Address of other nodes.
  2. These nodes gossip the data further to other nodes until the message is propagated far enough through the network to reach Bob’s Exit Tunnel.
  3. Bob receives the transaction/communication.

The Dusk Approach

Compared to similar solutions, the Dusk approach offers the following benefits:

1. Makes use of packet routing, instead of circuit routing. This means transparent load balancing of all networking message across peers, instead of a single tunnel.

2. Multiple packets are joined together in inconspicuous messages, making it exponentially difficult for an attacker to expose network communications.

3. True decentralization: it uses a distributed directory to have an overview of the network, as opposed to relying on a centralized bulletin board.

4. Uni-directional tunnels guarantee that incoming and outgoing traffic is kept decoupled; a measure engineered to enhance transmission unlinkability through data stream separation.

Conclusion

The ANL’s chief concern is to hide the identities of our transactors, most notably their IP Addresses. Many current privacy blockchains don’t have an IP obfuscation feature, and the implementation of Garlic Routing together with a gossip protocol ensures that a sender’s IP address will never be reconstructed.

How to learn more about Dusk Network
The Dusk Network is a project coordinated by the Dusk Foundation. We are a decentralized ecosystem entirely focused on providing the perfect trade-off between privacy and transparency. Dusk protects privacy and fits regulations in payments, communications and asset transfers.

Please consider joining us at the following media:

Website: https://www.dusk.network 
FAQ: https://www.dusk.network/faq
Telegram: https://t.me/dusknetwork
Twitter: https://twitter.com/duskfoundation
Reddit: https://reddit.com/r/dusknetwork
Linkedin: https://www.linkedin.com/company/duskfoundation/
GitHub: https://github.com/dusk-network