With this method, the sender encrypts the data using the receiver’s public key and then digitally signs the encrypted data.
In practice, a digital certificate that contains the digital signature is issued by a Certificate Authority (CA) that associates a public key with an identity.
A Complete Guide to Understanding This Blockchain Concept
Various schemes, such as RSA, Digital Signature Algorithm (DSA), and ECDSA-based digital signature schemes are used in practice.
RSA is the most commonly used; however, with the traction of ECC, ECDSA- based schemes are also becoming quite popular.
This is beneficial in blockchains because ECC provides same level of security that RSA does, but it uses less space.
Also, generation of keys is much faster in ECC as compared to RSA, therefore it helps with overall performance of the system.
The following table shows that ECC is able to provide the same level of cryptographic strength as an RSA based system with smaller key sizes: RSA key sizes (bits) Elliptic curve key sizes (bits) 1024 160 2048 224 3072 256 7680 384 15360 521 Comparison of RSA and Elliptic curve key sizes providing the same level of security The ECDSA scheme is described in detail in following subsection.
Why This Matters for Blockchain Technology
Understanding Encrypt then sign is not just an academic exercise — it has real-world implications for how blockchain systems are designed, deployed, and secured. Whether you are a developer building decentralized applications, a business leader evaluating blockchain adoption, or a curious learner exploring the technology, this knowledge provides a critical foundation.
Key Points to Remember
- Encrypt then sign With this method, the sender encrypts the data using the receiver’s public key and then digitally signs the encrypted data.
- In practice, a digital certificate that contains the digital signature is issued by a Certificate Authority (CA) that associates a public key with an identity.
- Various schemes, such as RSA, Digital Signature Algorithm (DSA), and ECDSA-based digital signature schemes are used in practice.
- RSA is the most commonly used; however, with the traction of ECC, ECDSA- based schemes are also becoming quite popular.
Conclusion
Encrypt then sign represents one of the many innovative layers that make blockchain technology so powerful and transformative. As distributed systems continue to evolve, a solid understanding of these core concepts becomes increasingly valuable — not just for developers, but for anyone building, investing in, or working alongside blockchain-powered systems.
Whether you are just starting your blockchain journey or deepening existing expertise, mastering these fundamentals gives you the tools to think clearly about decentralized systems and make smarter decisions in this rapidly evolving space.