What is Hashing and Encryption

Encryption is a system of muddling up a message in such a way that if you know the key you can get it back in clear. We use this for the pictures and for the sound files and any text notes on the Nurse's Computer in the Wound Image Program. This hides the data and identity of the patient in the normal way for a medical computer system.
Hashing is a way to muddle up a short text in such a way that it is impossible to get it back in clear. This is often used in computer systems to protect passwords. If you forget your password, the SysAdmin cannot tell you what it was (He cannot discover what it was), but he can give you a new one. We use hashing to protect the identity of the patient for the files that are on the web. Nobody, not even us, can decrypt these files to find out the phone numbers that underlie the hashed keys.
When the Nurse's computer is looking for 'her' patients, her computer knows the phone numbers of her patients, and checks to see if the hash of these phone numbers has a photo waiting. Very simple, very safe.
Another way we reduce the exposure of your pictures and identity is to avoid having it on the web at all. This means that photos are deleted as soon as they are downloaded, so they just are not there to be read by a hacker. Also data like your name, or the nurse's notes never goes to the web. It originates and stays on the nurse's computer in her office in a protected location.