# A security in depth approach to verifiable offchain computations

- Channel: [EthCC](https://streameth.org/ethcc)
- Date: 2024-08-08
- Duration: 23:51
- Topics: cybersecurity, ethereum, blockchain, scalability, proofs, layer 2, zk proofs, smart contracts
- Watch: https://streameth.org/watch/66b4a05a14dae87d37e11b9c

## Description

Hashi and SafeJunction are permissionless abstraction layers to create secure and future proof dapps. Hashi was designed to avoid bridging lock-ins and to enable higher degrees of security. SafeJunction extends this concept beyond cross-chain bridging, to verifiable arbitrary computations. The video discusses the importance of security in-depth for off-chain computations, particularly in the context of blockchain scalability and the use of proofs. The speaker explains how layer 2 and layer 3 solutions inherit security from Ethereum's base layer through proofs, which are essential for various applications like scalability, interoperability between layers, and external data verification through oracles. The concept of a "proof layer" is introduced as an abstract idea that is critical for blockchain security but does not yet exist in a concrete form.

The speaker then delves into three main use cases for proofs: improving scalability through vertical integration of layers, decomposability across different systems, and co-processing to offload heavy computations while maintaining transparency and privacy. They also discuss the potential future where everything in the blockchain ecosystem operates via proofs, with layer 1 blockchains primarily verifying these proofs.

However, there are challenges today in achieving this vision due to inefficiencies, fragmentation, trust assumptions, and high costs associated with proof generation and verification. Additionally, there are concerns about large attack surfaces and dependencies on unreliable code libraries.

To address these problems, the speaker suggests design principles such as avoiding vendor lock-ins, implementing security in depth by using multiple layers of protection, and designing systems that are future-proof to withstand potential risks over