Canton MainNet Upgrade to Adopt CantonBFT Ordering Runs on 10 October After a 24-Hour Topology Freeze
A scheduled Logical Synchronizer Upgrade moves the Global Synchronizer's ordering layer from CometBFT to Canton's own BFT service, after a delay that followed DevNet testing.
The Canton Network's production network was scheduled to switch the ordering layer of its Global Synchronizer to CantonBFT on 10 October 2026. The Canton Foundation's SV Operations schedule lists a MainNet Logical Synchronizer Upgrade (LSU) for 09:00 that day, marked as confirmed, with a one-line description: it adopts CantonBFT. A notice on the Canton forum gave the time as 9 am US Eastern.
What changes
The ordering layer is the part of the Global Synchronizer that puts transactions into sequence. A Canton forum update of 12 June described CantonBFT as a new Canton-native BFT ordering service prepared to replace CometBFT. A forum reply on 27 August said CantonBFT is based on the Narwhal and ISS protocols, and that more details of Canton's implementation would be published.
The change is delivered through an LSU, the upgrade method that went live on MainNet with Canton 3.5 at the end of June. According to the Canton Network, upgraded infrastructure runs in parallel and the switch is handled automatically, completing in seconds or minutes.
How the cutover was planned
- Topology freeze. A forum notice of 5 October said network topology would be frozen for 24 hours, from 9 am US Eastern on Friday 9 October to 9 am on Saturday 10 October.
- Transactions continue. Normal Daml transactions were to proceed during the freeze, with a pause of a few minutes around 9 am US Eastern on Saturday.
- Wallet users. Ledger told its users that during the maintenance they might not be able to add a new Canton account, while existing accounts and regular Canton transactions would not be affected.
A step that was postponed once
DevNet adopted CantonBFT in an LSU on 29 July. On 8 September, a forum update told operators that, based on the DevNet results, the Splice and Canton teams had recommended a temporary delay for TestNet and MainNet. If CantonBFT was ready in time, the post said, TestNet would follow on 29 to 30 September and MainNet on 9 to 10 October.
The schedule now shows the TestNet topology freeze on 29 September and the TestNet LSU on 30 September as confirmed, and the earlier August and September TestNet and MainNet slots as cancelled. At the time of writing, CantonCap had not seen a post-upgrade statement from the Canton Foundation or Digital Asset.
What comes next
The schedule lists the next MainNet LSU for 7 November 2026, after a topology freeze on 6 November. That upgrade adopts protocol version 36, which arrived with the Canton 3.6.1 and Splice 0.9.0 releases on 5 October. MainNet is listed to move to Splice 0.9.0 on 19 October.
Why it matters
Super Validators run the Global Synchronizer's core components and sequence its transactions, so the ordering software is core network infrastructure. This upgrade moves MainNet onto an ordering service built by the Canton teams, after one postponement. With a second protocol upgrade already on the calendar for November, validator operators and integrators face a busy upgrade cycle through the end of the year.
