BUIP014: Testing a Bitcoin Unlimited X-Relay Network for miners in mainland China
Proposer: Andrew Clifford
Submitted: 2016-03-03
Status: passed
Type: Operational BUIP
China map **Donation address**



This Operational BUIP is to support the initiative to build and test
Chinese mainland-based nodes for an alternative to the existing Relay
Network. Every BU v0.12 node has Xtreme Thinblocks & Xpress Validation
enabled by default and while nodes can connect in a random fashion for
multi-hop traffic, they can also be deliberately connected to optimize
for single-hop traffic. This is important for routing newly mined blocks
between the major miners, particularly so for miners which are on two
sides of the Great Firewall.

Phase I: Deployment

Setup of two nodes on hosting providers in different cities, ideally
where large hashing facilities operate.

Phase II: Testing

node-to-node performance statistics
a) within the firewall
b) through the firewall


BUIP014 will not be having a conventional membership vote. Its adoption
stands or falls on the level of donations it attracts. If members and
guests decide that the project benefits the decentralisation and growth
of Bitcoin then funds are welcomed!
Thanks to @Peter R for proposing
this project.

Unused funds will be returned to donors on a pro-rata basis, or rolled
forward for the next project if the donor agrees,


The X-Relay Network is to be detailed
By Peter Rizun

*Improving Block Propagation through the Great Firewall of China with
A Bitcoin Unlimited Initiative

The release of* ’Xtreme Thin

and Xpress Validation in ’Bitcoin Unlimited (BU)

has provided new opportunities to significantly improve the propagation
of blocks across Bitcoin’s peer-to-peer network.“’@Peter
”'s X-technology
leverages the fact that most transactions included in a solved block are
already known by most network nodes (common mempools). Rather than
requesting the solved block verbatim, the receiving node images its
mempool onto a Bloom filter that its sends with its get-data request.
The transmitting node sends the block contents by hash for all the
transactions imaged onto the Bloom filter, and in full otherwise.


*shows that this technique reduces the total number of bytes transmitted
by a factor of 15X under normal operating conditions.

Nowhere is the efficient propagation of blocks more important than
across the Great Firewall of China (GFC). For example,* ’experiments
in the fall of

by ’@jtoomim *showed that
although 4MB blocks could often be communicated and verified in 7
seconds (per hop), when the block had to penetrate the GFC, this figure
increased to between 15 to 150 seconds. Indeed, the difficulty in
propagating blocks through the GFC is arguably one of the most
significant bottlenecks to on-chain scaling.

The goal of this project is to setup and maintain a small network of BU
nodes across the world, with a particular focus on setting up nodes
inside and outside of mainland China, and to perform experiments to
quantify the improvements that X-technology permits. We suspect that the
average amount of time required to communicate each megabyte of block
information can be dramatically reduced. Should the results be positive,
this small network of BU nodes could grow into an “Xtreme Relay
Network,” eventually replacing the centralized and less-robust Fast
Relay Network, and permitting an order-of-magntitude or greater increase
in Bitcoin’s transactional throughput.

If you would like to contribute to this initiative, please consider
donating to the project’s wallet at 36XTMVtgJqqNYymsSvRonpUsbZRGkm1jvX.
All funds are administered by theZerg, Peter R & solex, in accordance
with Article 3 of* ’Bitcoin Unlimited’s Articles of