Interoperability Trilemma.
Great Systems Come With Huge Trade-offs.
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In my previous article, I talked about how & why blockchain needs interoperability.
This is the article https://link.medium.com/KCFAijEgaqb
I also mentioned why the Connext method of cross-chain bridging is currently the best in the blockchain space.
I will be laying more emphasis on how Connext is the best cross-chain bridge that ever existed.
Introduction
One of the critical things with building distributed systems is that there are always trade-offs.
This is the unfortunate nature of being in the blockchain industry, especially for bridges, because you want a combination of three properties in a bridge or an interoperable system.
- Trust-minimized: There should be no room for your bridge to be censored or assets being transferred rug pulled.
- Generalizable: It can send information across chains, not just only tokens.
- Extensible: You want to take the same system and replicate it on a different chain and rollups and other kinds of constructions without having to go and do custom work to integrate it.
No bridge construction has ever existed to fulfil these three properties.
Connext currently uses atomic swaps, and while it is trust-minimized and can be deployed easily to any chain, Connext cannot handle any arbitrary payload.
Connext can do some types of contract hauling across chains but not every kind of contract calling.
Similarly, we have MPC and Oracle systems, which many people refer to as multi-sig bridges.
Those things include layer zero and Synapse, which are very easy to deploy to many different chains, and they support arbitrary message passing, but they are not trust-minimized.
They have to trust an external set of actors that will have a different security model than the underlying blockchain.
Optimistic Bridges.
Nomad pioneered optimistic bridges.
It took another path along with this trade-off space, where it fulfilled the interoperability trilemma.
- They are generalizable.
- They are extensible
- They are trust-minimized.
They do these by optimistically relaying data across chains.
They post data on the receiving chain, and then there’s a specific timeout window, in Nomad’s case, 30 minutes, within which people can proof fraud.
There is another trade-off here, which is latency.
You can get all interoperability trilemmas, but it takes 30 minutes to execute transactions successfully.
Are users willing to wait for 30 minutes to make a cross-chain transfer?
Obviously, this is not acceptable to accelerate crypto adoption and improve cross-chain user experience.
So what did Connext do?
Connext Introduces Modularity.
Is there a way to beat this trade-off?
Connext is beating this trade-off through modularity by layering Connext on top of Nomad as a liquidity layer of the stack.
At the same time, Nomad serves as the messaging layer of the stack, and by doing this, Connext can offset some of its trade-offs and some of Nomad’s trade-offs.
And, most intriguingly, the outcome is that,
1. While retaining trust-minimized properties of the underlying chain, transfer of funds or an unpermissioned call happen within 2 minutes, which is the usual time it takes Connext to execute a transaction, instead of Nomad’s 30 minutes.
2. For permissioned calls (where you need to check transaction origin) that take 30 minutes of latency which is the standard Nomad time.
Generally, user-facing interactions are unpermissioned because you don’t want your broad set of users to be able to call a mint function on your token or give them the privilege only your administrative team members have because that’s going to be a security vulnerability on the Connext side.
