Dandelion++ on DigiByte is a network-layer privacy protocol that hides the originating IP address of transactions while leaving the public, auditable UTXO ledger fully transparent. DigiByte was the first major UTXO blockchain to ship it in production, enabling it by default in Core v7.17.2 in 2019.

What Is Dandelion++?

In a conventional peer-to-peer cryptocurrency network, a node that creates a transaction immediately announces it to all (or many) of its peers. Those peers relay it onward in a rapid flood (“diffusion”). An observer running many well-connected nodes can simply watch which peer announces a given transaction first. That timing correlation often reveals the originating IP address even though the on-chain DigiByte addresses themselves are only pseudonymous.

Dandelion++ closes this side channel. It splits propagation into two phases, inspired by the shape of a dandelion:

• Stem phase: The transaction is relayed privately along a single, randomly chosen path—one peer at a time. Each node on the path independently decides (with some probability) whether to continue the stem or switch phases. Transactions sit in a temporary “stempool” during this stage.
• Fluff phase: At a random point the transaction “flowers” and is broadcast with ordinary diffusion into the public mempool of the entire network.

Because the fluff begins after the transaction has already traveled an unpredictable path through intermediaries, network observers can no longer reliably map the first public announcement back to the true originator’s IP.

Importantly, Dandelion++ does not hide transaction amounts, addresses, or any other on-chain data. DigiByte remains fully public and auditable at the ledger level. It only removes a non-cryptographic network metadata leak.  

Why It Is Special

Several properties make DigiByte’s implementation stand out:

• Default and zero-cost. It is enabled by default for full nodes. There is no special transaction type, no extra fees, and no opt-in required for ordinary users. Privacy is simply the normal way transactions travel.
• Lightweight and backward-compatible. It is a pure relay-layer change. Older nodes continue to function; the protocol adds no consensus rules and does not slow DigiByte’s 15-second block times.
• Stronger than the original Dandelion design. Dandelion++ (the “++” version) improves resistance to graph-learning, intersection, and black-hole attacks through techniques such as approximately 4-regular anonymity graphs, per-inbound-edge routing, and epoch-based relay selection.
• Rare among major UTXO chains. Bitcoin never merged Dandelion or Dandelion++ into Core. Most large UTXO networks still rely on ordinary diffusion (or external tools such as Tor). DigiByte adopted it early and has kept it as a production feature for years. Only a handful of other chains (notably Monero and Grin) also run variants of the protocol.

Later work has explored extending stem-phase submission to SPV/light clients so mobile users can also benefit, further differentiating DigiByte.  

When It Was Introduced on DigiByte

Dandelion++ arrived with DigiByte Core v7.17.2, released in early May 2019 and enabled by default. The same release prepared the network for the Odocrypt algorithm upgrade (activated at block ~9.1 million in July 2019). Official DigiByte timelines list “Odocrypt & Dandelion++” together under 2019 as one of the project’s key protocol firsts.

It has remained part of the codebase through subsequent major upgrades (including the v8 and v9 lines) and continues to be highlighted in official documentation and developer communications as a core privacy feature.  

How Dandelion++ Helps Make DigiByte a More Complete Blockchain

A “complete” public blockchain needs more than fast blocks and a sound monetary policy. It needs layered defenses that address real attack surfaces without sacrificing the properties that make the system useful:

• Speed & scalability: 15-second blocks, early SegWit, low fees.
• Security & decentralization: Five independent mining algorithms (MultiAlgo), real-time difficulty adjustment (DigiShield / MultiShield), and the adaptive Odocrypt algorithm that changes every 10 days.
• Functionality: DigiAssets for tokenized assets, Digi-ID for decentralized authentication, and (more recently) the native DigiDollar stablecoin.
• Network privacy: Dandelion++.

Without Dandelion++, the network layer remained a soft underbelly. Even with strong on-chain pseudonymity, an adversary who could map transactions to IP addresses could undermine real-world privacy. By closing that specific leak at the relay layer while preserving full ledger transparency DigiByte added the missing piece of its original design goals: a fast, secure, decentralized UTXO chain that also protects users at the point where transactions first enter the network.

In short, Dandelion++ does not turn DigiByte into a privacy coin. It makes DigiByte a more rounded, production-ready public blockchain: one that delivers speed, multi-algorithm security, useful application layers, and sensible default protection against network-level surveillance all without compromising auditability or adding friction for ordinary users.