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Can anybody help me to understand or a reference link to understand below keys mentioned in config parameter of genesis file

 "config": {
   "chainID": 68,
   "homesteadBlock": 0,
   "ByzantiumBlock" : 0,
   "eip155Block": 0,
   "eip158Block": 0

marked as duplicate by Richard Horrocks, Achala Dissanayake, Briomkez, Ismael, GrandFleet Nov 19 '18 at 23:16

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.


chainId: Identifies blockchain, the main Ethereum chain has its own ID, but you will need to set it to a unique value for your private chain.

homesteadBlock: Homestead is the second major version of the Ethereum platform and is the first production release of Ethereum. It includes several protocol changes. So, if you are on homestead version, this attribute is 0

ByzantiumBlock: Indicates that Byzantium is enabled in your private network.

eip155Block/eip158Block: Homestead version was released with a few backward-incompatible protocol changes, and therefore requires a hard fork. These protocol changes/improvements proposed through a process Ethereum Improvement Proposals (EIPs). If your chain won’t be hard-forking for these changes leave as 0

  • Do we need to keep all the entry. I mean if I keep ByzantiumBlock only, will it work – Basilji Aug 27 '18 at 7:57

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