BitcoinCash/specification
1
Fork 0
Code Issues Pull Requests Releases Activity

wiki commit

Browse Source
This commit is contained in:
bitcoin
2019-12-05 11:08:18 -05:00
committed by buwiki
parent 7f24156628
commit 5a55ebadf7
1 changed files with 18 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files
protocol/network/messages/version.md
+16 -2
View File
@@ -1,5 +1,8 @@
# Handshake: Version (“version”)
The version message is a part of the node connection handshake and indicates various connection settings, networking information, and the services provided by the sending node (see Services Bitmask below).
## Message Format
## Services Bitmask
The services field is an 8 byte little-endian-serialized bitfield that described peer capabilities. The following capabilities are defined, by bit position:
@@ -39,7 +42,10 @@ The services field is an 8 byte little-endian-serialized bitfield that described
* 8: SLP_INDEX_ENABLED <img src="/_static_/images/warning.png">
Indicates that the node tracks Simple Ledger Protocol validity and supports returning this status for individual transactions.
#### Proposed
#### Other Proposed/Previously Used Service Flags
* 1: NODE_GETUTXO <img src="/_static_/images/warning.png">
The node is capable of responding to the getutxo protocol request. See [BIP 64](https://github.com/bitcoin/bips/blob/master/bip-0064.mediawiki) for details on how this is implemented. _Was previously supported by Bitcoin XT only._
* 7: NODE_WEAKBLOCKS <img src="/_static_/images/warning.png">
The node supports Storm weak block (currently no node supports these in production, so this is a placeholder).
@@ -47,5 +53,13 @@ The services field is an 8 byte little-endian-serialized bitfield that described
* 8: NODE_CF <img src="/_static_/images/warning.png">
Indicates the node is capable of serving compact block filters to SPV clients, AKA the "Neutrino" protocol ([BIP157](https://github.com/bitcoin/bips/blob/master/bip-0157.mediawiki), and [BIP158](https://github.com/bitcoin/bips/blob/master/bip-0158.mediawiki)).
* 9: NODE_NETWORK_LIMITED <img src="/_static_/images/warning.png">
* 10: NODE_NETWORK_LIMITED <img src="/_static_/images/warning.png">
This means the same as NODE_NETWORK with the limitation of only serving a small subset of the blockchain. See [BIP159](https://github.com/bitcoin/bips/blob/master/bip-0159.mediawiki) for details on how this is implemented.
## Node-Specific Behavior
Generally, though node implementations may be aware of services they do not provide, they generally ignore those they don't supported. Any notable deviations from that behavior are documented below.
### Bitcoin ABC
Bitcoin ABC nodes may, once they have reached their maximum number of peers, selectively disconnect from nodes that do not supported "desired services", though it appears currently this just <code>NODE_NETWORK</code> and/or <code>NODE_NETWORK_LIMITED</code>. That is, it may prefer nodes that store and serve blocks.