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BIP 102: Block size increase to 2MB

Also known as: BIP102, BIP-0102.

In plain English: Proposed a single, simple increase in the maximum block size from 1 MB to 2 MB to allow more transactions per block. Being a change that older software would reject, it would have required a hard fork, and it was one of the competing options in the block size debate.

Status
Closed
Type
Specification
Layer
Consensus (hard fork)
Authors
Jeff Garzik
Assigned
Last changed
Topics
Capacity, Blocks
Source
bip-0102.mediawiki on GitHub · Markdown

Full specification

Abstract

Simple, one-time increase in total amount of transaction data permitted in a block from 1MB to 2MB.

Motivation

  1. Continue current economic policy.
  1. Exercise hard fork network upgrade.

Specification

  1. MAX_BLOCK_SIZE increased to 2,000,000 bytes at trigger point.
  1. Increase maximum block sigops by similar factor, preserving SIZE/50 formula.
  1. Trigger: (1) Block time 00:00:00 on flag day, AND (2) 95% of the last 1,000 blocks have signaled support.

Backward compatibility

Fully validating older clients are not compatible with this change. The first block exceeding 1,000,000 bytes will partition older clients off the new network.

Discussion

In the short term, an increase is needed to continue to current economic policies with regards to fees and block space, matching market expectations and preventing market disruption.

In the long term, this limit should focus on reflecting the maximum network engineering limit.

Implementation

https://github.com/jgarzik/bitcoin/tree/2015_2mb_blocksize

Questions about BIP 102

What is BIP 102?

BIP 102, “Block size increase to 2MB”, is a specification Bitcoin Improvement Proposal written by Jeff Garzik and assigned in June 2015. Proposed a single, simple increase in the maximum block size from 1 MB to 2 MB to allow more transactions per block. Being a change that older software would reject, it would have required a hard fork, and it was one of the competing options in the block size debate.

Is BIP 102 active?

No. BIP 102 is Closed: it is no longer being pursued because it was withdrawn, rejected or replaced by a newer proposal.

Who wrote BIP 102?

BIP 102 was written by Jeff Garzik. Its number was assigned on June 23, 2015.

Which BIPs build on BIP 102?

1 other BIP references BIP 102: BIP 123 (BIP Classification).

Where can I read the full BIP 102 specification?

The complete text of BIP 102 is on this page, taken unchanged from the official bitcoin/bips repository on GitHub. It is also available as Markdown and JSON.

BIPs that build on BIP 102

  • BIP 123: BIP Classification: Deployed. Sets out a way to classify BIPs into layers, such as consensus, peer services, APIs and applications, according to which part of the system they affect. This helps readers judge how widely a…

Learn more

Glossary

Related proposals

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