Many resources talk about the benefit of Proxy Re-encryption (PRE) and I also implement my PRE using Elliptic Curve key pair. But after I set up Global parameters, I can encrypt very small data maybe less than 1KB. My question is with EC key pair normally, can we encrypt large data maybe about 10MB?
Normally the data is not encrypted under PRE directly. The sender can encrypt the data using a random symmetric key using a secure symmetric cipher (e.g. AES), then encrypts the symmetric key under the sender's PRE key. The proxy can re-encrypt this ciphertext into a new ciphertext such that the receiver can decrypt it.