Imaging Informatics: Chain Links
By Dave Yeager
Vol. 18 No. 9 P. 6
A technology that’s most often associated with digital currency may soon change the way medical images are shared. Blockchain, which was initially used as the database for Bitcoin, is a method for logging transactions in a way that can’t be changed. Because of this security and its ease of use, the technology offers the potential for faster, more efficient, and secure image exchange.
Chris Hafey, chief technology officer at NucleusHealth, says several factors make blockchain an effective exchange medium. One is its decentralized nature. Nobody owns a blockchain, and copies of it exist on many computers. To effectively change a ledger, identical changes would need to be made on every system that has a copy of it.
In addition, the cryptography used with blockchain is considered unbreakable. Two key aspects of this cryptography are hashing and digital signatures. Hashing creates a unique identifier for a set of data.
“What a hashing function does is take a piece of data of any length, and it creates a fixed-length number, maybe 40 bytes long, that represents that input data,” Hafey says. “And it’s a one-way transaction, so, given that original data set, you can produce a hash, but you can’t produce the original data set from the hash. It takes big data and makes a small number representing it.”
Hashing functions protect data integrity because any change, no matter how small, to the original data file will generate a different hash number. Essentially, Hafey says, hashing creates a virtual fingerprint for an image. Coupled with a digital signature, hashing ensures that images are shared securely.