TON Catchain 2.0 consensus QUIC Communication Port 

The following information applies solely to TON nodes that are actively participating in network validation. Operators of TON nodes in other modes, such as full nodes or lite servers, do not need to follow the instructions below.

Introduction

The Catchain 2.0 consensus mechanism separates the traffic required for the validation process from the normal TON network RLDP traffic. The QUIC protocol was chosen to exchange information between nodes that actively participate in the validation mechanism.

Validator nodes must open an additional UDP network port for QUIC communication. As with the classical RLDP port, all validators must be reachable from the public internet on the QUIC port. Operators who place their validator nodes behind NAT and/or firewalls must ensure that traffic to and from the QUIC port is whitelisted and transparently forwarded to the validator node.

Activation Roadmap, Deadlines, and Consequences

March 31, 2026: Rollout of v2026.03, including support for the QUIC protocol and its configuration. Please note that the protocol is not yet active and the port is not utilized.

April 8, 2026: Rollout of v2026.04 with minor fixes and QUIC tooling. Voting procedure for the full activation of Catchain 2.0 consensus.

The time period between node software update and full activation of Catchain 2.0 consensus should be used by validators to ensure that QUIC ports on their machines are operational. Please see last chapter of this publication for information on how to perform the check.

April 9, 2026: Full activation of Catchain 2.0 consensus following successful voting procedure.

All validator nodes must configure and activate their QUIC ports by the end of the day on April 8, 2026. Validators that fail to activate the QUIC port will not be able to perform their validation duties and will endanger network stability.

Port configuration

Validator operators have four options for adjustment of QUIC port:

1)  Use defaults.

Unless configured otherwise, the node will use its main RLDP port number, increased by 1000, for QUIC communication. For example, if your node used UDP port 10000, it will use UDP port 11000 for QUIC.

Please be aware that your main node port must be =< 64536 for this to function, if your main node port is above 64536 you need to adjust it or define custom QUIC port using methods outlined below.

Verify the functionality of the QUIC port on your validator node using the instructions at the end of this publication.

2) Use mytonctrl.

Adjustments by the mytonctrl can be performed online without stopping the validator process.

Following the v2026.04 software update on April 8, you will be able to use mytonctrl to manage the QUIC port.

To set custom QUIC port use command: 

set_quic_port <port_number>

To revert to default +1000 setting use command:

set_quic_port 0

3) Use the validator-engine-console.

Adjustments by the validator-engine-console can be performed online without stopping the validator process.

Switch your validator ADNL address to category 2 with the command

add-adnl <adnl_hash> 2

Where adnl_hash is the base64-encoded hash of your validator ADNL address.

Set a custom QUIC port, using the command

add-quic-addr <ip>:<port> [ 2 ] [ ]

Where ip is the public IP address of the validator and port is the custom port number.

For example:

add-quic-addr 8.8.8.8:15000 [ 2 ] [ ] 

4) Manual adjustment of the node configuration file.

Manual adjustments cannot be performed online. You must stop the validator-engine process during the adjustment.

Switch your validator ADNL address to category 2

Find your validator ADNL address in the .adnl leaf of the configuration file, and set the category field to 2.

Define the QUIC listener.

Add or adjust the element within the .addrs leaf of the configuration file as follows:

  {
   "@type": "engine.quicAddr",
   "ip": <ip_dec>,
   "port": <port>,
   "categories": [
    2
   ],
   "priority_categories": []
  }

Where ip_dec is the public IP address of the validator in decimal format (you can copy the value from the "engine.addr" element of the .addrs array), and port is the desired port number.

Testing Network Communication

Because the QUIC protocol will be activated following the full Catchain 2.0 activation, and only once a node is actively participating in the validation process, it is not possible to test the node's functionality beforehand.

We advise testing your NAT/firewall infrastructure as follows:

On validator host
Start netcat UDP listener on desired QUIC port

nc -u -l -p <port>

Send test packet from remote host on the internet, outside of security perimiter

echo “hello QUIC” | nc -u <public_ip> <port> -w 3

If UDP packet was able to reach the validator you will see string “hello QUIC” on console of validator.

Validating QUIC port functionality

To check status of QUIC port, please visit https://validators.ton.org/ 30 minutes after you perform update of node software to latest version and check value of QUIC field for your validator hosts. Possible values and their meaning are:

OK: QUIC port has been publishes by your node and ingress connection to that port is possible.
NOK: QUIC port has been publishes by your node but ingress connection to that port is possible, please check your Firewall / NAT
n/a: QUIC port has not been publishes by your node. Please ensure that you have updated the node software

Please note that status of nodes on dashboard is updated approximately each 15 minutes, changes applied to your infrastructure will not become immediately visible on dashboard.