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Bitcoin Dev Archive 2017

BIP148 temporary service bit (1 << 27)

3 messages, 19 Jun 2017. Started by Luke Dashjr.

Luke Dashjr, Tom Zander, Mark F

Permalink Original thread on gnusha.org

Luke Dashjr permalink original

To ease the transition to BIP148 and to minimise risks in the event miners choose to perform a chain split attack, at least Bitcoin Knots will be using the temporary service bit (1 << 27) to indicate BIP148 support.

Once the transition is complete, this will no longer be necessary, and the bit will be (manually) returned for reuse.

I encourage other software implementing BIP148 (both full and light nodes) to set and use this service bit to avoid network partitioning risks.

Luke

Tom Zander in reply to Luke Dashjr permalink original

On Monday, 19 June 2017 21:26:22 CEST Luke Dashjr via bitcoin-dev wrote:

Quoted text (9 lines)
> To ease the transition to BIP148 and to minimise risks in the event miners
> choose to perform a chain split attack, at least Bitcoin Knots will be
> using the temporary service bit (1 << 27) to indicate BIP148 support.
>
> Once the transition is complete, this will no longer be necessary, and the
> bit will be (manually) returned for reuse.
>
> I encourage other software implementing BIP148 (both full and light nodes)
> to set and use this service bit to avoid network partitioning risks.

I'm curious what you action on the finding (or not) of a peer with this bit set (or not). Can you link to the github commit where you implemented this?

Mark F in reply to Tom Zander permalink original

It is essential that BIP-148 nodes connect to at least two other BIP-148 nodes to prevent a network partition in August 1st. The temporary service but is how such nodes are able to detect each other.

Quoted text (24 lines)
> On Jun 19, 2017, at 12:46 PM, Tom Zander via bitcoin-dev <bitcoin-dev@lists•linuxfoundation•org> wrote:
>
>> On Monday, 19 June 2017 21:26:22 CEST Luke Dashjr via bitcoin-dev wrote:
>> To ease the transition to BIP148 and to minimise risks in the event miners
>> choose to perform a chain split attack, at least Bitcoin Knots will be
>> using the temporary service bit (1 << 27) to indicate BIP148 support.
>>
>> Once the transition is complete, this will no longer be necessary, and the
>> bit will be (manually) returned for reuse.
>>
>> I encourage other software implementing BIP148 (both full and light nodes)
>> to set and use this service bit to avoid network partitioning risks.
>
> I'm curious what you action on the finding (or not) of a peer with this bit
> set (or not).
> Can you link to the github commit where you implemented this?
> --
> Tom Zander
> Blog: https://zander.github.io
> Vlog: https://vimeo.com/channels/tomscryptochannel
> _______________________________________________
> bitcoin-dev mailing list
> bitcoin-dev@lists•linuxfoundation•org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev