The spam attack caused the Nano network to slow down and become out of sync

The spam attack caused the Nano network to slow down and become out of sync

A spam attack with” junk ” transactions disrupted the Nano network. Node operators have limited their bandwidth, network synchronization is disrupted, and some transactions are blocked.

The Nano network uses so-called direct acyclic graphs (DAGs) to settle transactions on the network, rather than the blockchain. Unlike the blockchain, which is a single unified and continuous transaction history, the Nano DAG registry consists of multiple branches of asynchronous transaction histories. This design guarantees very low transaction fees. But, as the latest attack shows, this is due to a decrease in decentralization and the level of resistance to Sybil attacks.

On Thursday morning, in the Discord Nano channel, users complained about unconfirmed transactions and unsynchronization of block browsers.

“This morning I sent some NANO. Nault [wallet] reports sending, but the recipient hasn’t confirmed the transaction yet. Usually the translation takes a few minutes” – wrote one of the users in the channel
supports Discord Nano.

Another user who manages two separate Nano nodes noticed a discrepancy in the network data.

The user complains about the disparate data displayed by the two nodes under his control (screenshot from the Discord Nano channel)

According to a post on Reddit, the problems started when the Nano network was flooded with” junk ” transactions with almost zero value. In response, Nano creator Colin LeMahieu advised node operators to reduce throughput to accept fewer incoming transactions. This led to the fact that the network almost stopped working, as one user Nano hanzyfranzy writes:

“The Nano global network is not working. Probably, the situation is unlikely to change until the node operators change their configurations. Some transactions go through, but it’s just a drop in the bucket.”

Colin Lemahieu said node synchronization was disrupted due to an attack that exposed “CPU and disk usage limitations” for the nodes.

“Lowering the bandwidth limit saves disk and CPU resources so that they can synchronize. The network was running at 70 transactions per second for more than a week, and the nodes stopped syncing. When network participants lower the bandwidth limit, it reduces transaction processing speed and allows them to catch up. Unfortunately, the attacker took advantage of this node state, so re-syncing is slow, ” Lemahieu said.

Lemahieu believes that the attackers targeted Nano to interfere with the release of version 22, which is being worked on by a team of five people. The attackers have stopped the attack for now, and Lemahieu said the network is “slowly recovering,” but did not give a timeline for fully restoring it to normal operation.

Recall that last summer, the Chainlink price oracle network was attacked
spam attack-the attackers generated a lot of requests to the network nodes, so that there were interruptions in the work. In August 2018, a spam attack on the Ethereum network caused transaction

Veterans of the cryptocurrency community well remember a series of spam attacks on the Bitcoin network in 2015-2016
years, when tens and even hundreds of thousands of “junk” transactions filled all the blocks, causing transaction delays for ordinary users and a multiple increase in network fees.