Understanding the Security of the Protocol

Hi All,

I’m completely new here and I love all the work that’s going on at Cardano, from the outside it looks like a strong team with great leadership.

I’ve been trying to familiarise myself with the Ouroboros protocol and something I am trying to get my head around concerns the section on the security of the protocol.

The Ouroboros paper states, ‘the protocol is secure under a number of plausible assumptions’. One such assumption is:

*** “(3) the stakeholders do not remain offline for long periods of time”**

Imagine the stakeholder does go offline forever, for many possible reasons, is it still secure? How is this handled?

It might be glaringly obvious, so please forgive me if that’s the case.

Many Thanks,

Hi - I believe the reference you are quoting really refers to a large amount of stakeholders all going offline for a long period of time, not simply a single stakeholder.

The more that go offline, the smaller the pool of slot leaders to randomly pick from, and thus the 51% takeover attack becomes numerically easier. (Basically no crypto is secure if someone can control 51% of the block signings).

Hope that helps!



Ahh yes, that makes perfect sense. I should have paid attention to stakeholders.

Thanks for clarifying!


Also keep in mind, even if such an event occur, it will affect current transactions, cause after recovery it is expected most honest nodes will sync to a legitimate chain ! that is your funds will be secured!

Yes, this is a big worry. This is why we are adding a delegation system on top of the POS protocol. The protocol needs X% of people to be online and we want to ensure security.