The company bloXroute labs recently launched their Distribution Network (BDN) that uses a layer zero solution for scalability. On blockchains, Layer 0 is where blocks are propagated beneath the blockchain and that is where the scalability problem lies.

The BDN uses servers all over the globe that are optimized using encryption, compression, and other techniques to allow the blocks to propagate faster.

The solution solves the scalability problem at the underlying peer-to-peer (p2p) network level because of its limitations. BDN does not interfere with blockchain consensus models and can be used by any blockchain right now. The only things that would need to be adjusted are the block size and inter-block time interval to take advantage of bloXroute's network capacity.

bloXroute does not want to compromise the decentralization of control over transactions and rather embrace BDN to enable scaling.

Source: bloxroute BDN Whitepaper

Fig. 1. The components of the bloXroute system: the bloXroute BDN, and the Peer Network nodes utilizing it. Each Peer Network node runs a Gateway process as an intermediary between its blockchain application and the bloXroute BDN

Running each node as a gateway makes them operate as if they are on the same Local Area Network (LAN) while being at different locations across the globe.

To achieve scalability, they are also using a system-wide caching and gigabyte sized blocks.

The BDN propagates blocks without needing to know the amount, wallet addresses, or the transactions they contain. Arbitrary transactions can also be included by miners. Additionally, bloXroute cannot collude or favor nodes and provide blocks ahead of others. Nodes can't be prevented from joining the system and using it.

For bloXroute to remain neutral, they support encrypted blocks. That is how blocks can propagate without knowing whats in the blocks. Only after the block is propagated, the encryption key is revealed. Gateways will not propagate blocks directly to bloXroute but instead relay them to peers in the p2p network. This creates a "shuffling" of blocks that prevent knowing where they originated from.

bloXroute will provide the use of BDN for free but is limited to a throughput of 100 transactions per second (TPS). To maintain the sustainability of bloXroute, node operators can opt-in to include a small fee to bloXroute. Blocks that have included the fee will have higher priority and part of the network capacity will be dedicated to them.

More in-depth details are in the bloXroute BDN whitepaper.

Back in July of 2019, bloXroute had been testing BDN with the Bitcoin Cash testnet mining to measure the performance with and without BDN.

Results

The BDN propagates large blocks (32MB) between 2–18 seconds compared to up to 193 seconds without bloXroute. (Propagation times include block validation, which we have seen take between 1–5 seconds on large blocks).

China saw the largest improvement in propagation times. For example, a node in Beijing processed large blocks between 17–151 seconds without bloXroute and 3–7 seconds with.

Block compression technology, such as Compact blocks, improved with the BDN as transaction propagation allowed mempools to be more in sync .

The BDN sped up fork recoveries (e.g. recover missed transactions included in compact blocks). -Medium

Why did they choose Bitcoin Cash's testnet?

They chose the bitcoin protocol because it has the highest market share but went with Bitcoin Cash instead of Bitcoin core because Bitcoin core only supports 1MB blocks. The testnet was used because the test consisted of creating millions of transactions and would be extremely costly to carry out the test on the mainnet.

For the test, bloXroute partnered with the largest mining pools around the world and get as close to real-world conditions as possible.

Source: Medium

Miners installed the bloXroute gateway that followed this architecture:

Source: Medium

The test consisted of two phases: Phase 1: Miners mine without the bloXroute Gateway to establish a baseline

Phase 2: Miners mine with the bloXroute Gateway to measure performance

Source: Medium

Source: Medium

Source: Medium

The current version of BDN at the time of writing this is up to v1.52.5 but from v1 supports Bitcoin Cash and Ethereum.

If you are a node operator and would like to implement the Blockchain Distribution Network, you can find the documentation here or you can visit their Github.